Laboratory
12
Evidences of Evolution
(LM pages 125–141)
Fourth Edition
Section 12.2 now includes an Observation in which hominid skulls are compared. New
illustrations have been added.
New or Revised Tables: 12.8 Other Hominid Craniums Compared to Human Cranium;
12.9 Other Hominid Faces Compared to Human Face; 12.10 Other Hominid Dentition
Compared to Human Dentition
MATERIALS AND PREPARATIONS
Instructions are grouped by exercise. Some materials may be used in more than one
exercise.
12.1
Evidence from the Fossil Record (LM pages 126–130)
_____ Fossil collections are available from various supply houses and prices are
variable.
12.2
Evidence from Comparative Anatomy (LM pages 131-138)
Skeletons or mounted forelimbs (LM pages 131-132)
_____ lizard
_____ bird (pigeon)
_____ bat
_____ bat skeleton plastomount
_____ cat
_____ human, adult (see Carolina’s “Skeletons: Human” section)
_____ chimpanzee
Comparison of Vertebrate Embryos (LM page132-133)
_____ slides, prepared: chick, reptile, fish embryos
_____ microscope, stereomicroscope
_____ lens paper
Comparison of Chimpanzee and Human Skeletons (LM page 133-136
_____ Complete chimpanzee and human skeletons
Comparison of Extinct Hominid skulls (LM page 136-138)
These skulls are available:
_____ Australopithecus afarensis skull
_____ Australopithecus aethiopicus cranium
_____ Australopithecus boisei cranium
_____ Homo erectus skull
_____ Homo heidelbergensis cranium
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_____ Homo neanderthalensis skull
_____ Cro-Magnon cranium
12.3
Molecular Evidence (LM pages 138–140)
_____ Immunology and Evolution Experiment kit (Lab-Aids, Inc. 92)
_____ Immunology and Evolution Experiment replacement kit (Lab-Aids, Inc
92-RC)
_____ stirring rod, plastic; or toothpicks
EXERCISE QUESTIONS
12.1 Evidence from the Fossil Record (LM pages 126–30)
Geologic Timescale (LM pages 126–28)
Divisions of the Timescale (LM page126)
List the four eras in the timescale, starting with Precambrian time: Precambrian,
Paleozoic, Mesozoic, Cenozoic
1. Why do you read the timescale starting at the bottom? The earliest dates are at
the bottom.
2. During the Mesozoic era and the Jurassic period, the first flowering plants
appear. How many million years ago was this? 199.6–125.5
3. How do you know that the plants in this forest were not flowering trees as most
of our trees are today? Flowering trees had not evolved yet. What type animal was
diversifying at this time? amphibians
4. During what period and epoch did primates appear? Tertiary, Paleocene During
what period and epoch did hominins appear? Tertiary, Pliocene What period and
epoch is the age of Homo sapiens? Quaternary, Holocene
Dating Within the Timescale (LM page 128)
Why wouldn’t you expect to find human fossils and dinosaur fossils together in
rocks dated similarly? Humans had not evolved yet.
Limitations of the Timescale (LM page 128)
Which of the animals shown in Figure 12.1 suffered the most during the P-T
(Permian-Triassic) extinction? poriferans (sponges)
Which of the animals shown in Figure 12.1 became extinct during the K-T
extinction? dinosaurs
Fill in the eras on the lines provided in Figure 12.1. Paleozoic, Mesozoic, Cenozoic
Fossils (LM pages 129-30)
The fossil record relies heavily on anatomical data. Why would that be? Because the
anatomy of the organism is preserved as a fossil.
Observation Invertebrate Fossils (LM page 129)
1.
One possible reason the Cambrian might be rich in fossils is that organisms
now had shells and bones.
Table 12.2 Invertebrate Fossils Answers will vary according to the fossils in the kit.
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Observation Vertebrate Fossils (LM pages 129-30)
Table 12.3 Vertebrate Fossils Answers will vary according to the fossils in the kit.
Observation Plants Fossils (LM pages 130)
Table 12.4 Plant Fossils Answers will vary according to the fossils in the kit.
Summary of Evidence from Fossil Record (LM page 130)
1. Fossils are past evidence of organisms preserved in the Earth's crust.
2. Younger fossils and not older fossils are more like living organisms.
3. In short, the fossil record shows that life has a history.
12.2 Evidence from Comparative Anatomy (LM pages 131-–38)
Observation: Vertebrate Forelimbs (LM page 131)
2. Label in Figure 12.3 the corresponding forelimb bones of the frog, the lizard, the
bird, the bat, the cat, and the human. Follow the color coding to correctly label the
bones.
3. Fill in Table 12.5 to compare bones in vertebrate forelimbs to ancestral condition.
Table 12.5 Comparison of Vertebrate Forelimbs*
Animal
Bones That Resemble
Bones That Differ from
Common Ancestor
Common Ancestor
Frog
h, m
u, r, c, p
Lizard
h, u, r, c, m
p
Bird
h, u, r
c, m, p
Bat
h
u, r, c, m, p
Cat
h, c, m, p
u, r
Human
u, r, c, m, p
h
*
Note: This comparison is relative, and student answers will vary.
4. Relate the change in bone structure to mode of locomotion in two examples.
Example 1: Bat: the radius is long, relative to the humerus. The phalanges are
extremely long, and the bat’s skin is stretched out over the forelimb forming a wing
for flying.
Example 2: Humans: Because humans walk upright, their forelimbs are no longer
used to bear weight. Their long upper limbs have carpals, metacarpals, and
phalanges that are modified for object manipulation. The shape and angle of
articulation of the first digit (the thumb) are particularly noteworthy. This opposable
thumb allows for maximum manipulation. These capabilities could not be so
specialized if humans were quadrapeds.
Conclusion: Vertebrate Forelimbs (LM page 132)
• Vertebrates are descended from a common ancestor, but they are adapted to
various ways of life.
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Comparison of Vertebrate Embryo (LM pages 132-33)
What does this tell you about their evolutionary relationship? Reptiles are more
closely related to birds than fish.
Observation: Vertebrate Embryos (LM page 133)
2. List five similarities of the embryos.
a. General shape of presumptive head
b. Shape and orientation of limb buds
c. Presence and shape of the tail
d. Presence of pharyngeal pouches
e. Placement of the eyes in relationship to the rest of the head
f. Presence and position of yolk stalk
Conclusion: Vertebrate Embryos (LM page 133)
Vertebrate embryos resemble one another because they are related through evolution.
Observation: Chimpanzee and Human Skeletons (LM pages 133–36)
Posture (LM page 133-35)
Table 12.6 Comparison of Chimpanzee and Human Postures
Skeletal Part
Chimpanzee
Human
1. Head and spine Thrust forward over hips and legs Balanced over hips and legs
2. Spine
Short and stiff
Long and curved
3. Pelvis
Long and narrow
Broad and short
4. Femur
Straight, no angle
Angled between
articulations
5. Knee joint
Femur about the same size top and Femur larger at bottom
bottom, tibia about the same size
Tibia larger at top
top and bottom
6. Foot
Opposable toe
Yes
No
Arch
No
Yes
2. (Referring to comparison of spines in Table 12.6)): How does this contribute to
an erect posture in humans? allows the weight to be balanced above the pelvis
6. (Referring to comparison of foot in Table 12.6): In which animal is the big toe
opposable? Chimpanzee How does an opposable toe assist chimpanzees? allows
them to grasp tree limbs with feet Which foot has an arch? Human foot How does
an arch assist humans? helps them walk erect
7. How does the difference in the position of the foramen magnum, a large opening
in the base of the skull for the spinal cord, correlate with the posture and stance
of the two organisms? In the human, the foramen magnum is placed almost in the
bottom center of the skull; in the chimpanzee, the opening is well to the rear. Humans
walk upright, and chimpanzees use all four limbs for walking.
Skull Features (LM page 135)
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Table 12.7 Facial Features of Chimpanzees and Humans
Feature
Chimpanzee
Human
1. Supraorbital ridge
More thick
Not as thick
2. Saggital crest
yes
no
3. Slope of frontal bone
Slope
No slope
4. Teeth
Incisors angled,
Incisors vertical
canines overlap,
canines overlap
molars massive
molars smaller
5. Chin
Projects
Does not project
Conclusion: Chimpanzee and Human Skeletons (LM page 136)
• Do your observations show that the skeletal differences between chimpanzees
and humans can be related to posture? yes Explain. All changes noted in human
skeleton assist in walking erect.
• Do your observations show that diet can be related to the facial features of
chimpanzees and humans? yes Explain. Chimpanzees eat more plant material than
humans, and humans eat more meat than chimpanzees.
Comparison of Extinct Hominid Skulls (LM page 136-38)
Observation: Extinct Hominid Skulls
Tables 12.8, 9, 10 Data will vary according to skulls available and chosen by students.
Conclusions: Extinct Hominid Skulls (page 138)
 Answers will vary dependent on student observations
12.3 Molecular Evidence (LM pages 138-140)
Why can comparing amino acid data lead to the same conclusions as comparing
DNA data? The sequence of bases in DNA determines the sequence of bases in a protein.
Protein Similarity Evidence (LM pages 167–69)
Experimental Procedure: Protein Similarity Evidence
5. Describe what you see. A distinct cloudiness or precipitate forms.
7. At the end of 10 and 20 minutes, record the amount of precipitate in each of the
six wells in Figure 12.10.
Conclusions: Protein Similarity Evidence (LM page 169)
• The last row of Figure 12.12 tells you that the test serum in well 3 is from a
human. How do your test results confirm this? It has the same amount of
precipitate as well 6.
• Aside from humans, the test sera (supposedly) came from a pig, a monkey, an
orangutan, and a chimpanzee. Which is most closely related to humans—the pig
or the chimpanzee? chimpanzee
• Judging by the amount of precipitate, complete the last row in Figure 12.8 by
indicating which serum you believe came from which animal. See above. On
5
•
what do you base your conclusions? The greater the degree of precipitation, the
more similar the animal’s blood serum antigens are to those in human blood serum.
Molecular evidence shows us that of the vertebrates studied, chimpanzees and
humans are most closely related.
LABORATORY REVIEW 12 (LM page 141)
1.
List three types of evidence that various types of organisms are related
through common descent. fossil record, comparative anatomy, molecular evidence
2.
Why would you not expect a fossil buried millions of years ago to look exactly
like a modern-day organism? Evolution has occurred.
3.
A horseshoe crab has changed little in approximately 200 million years of
existence. Would you expect to find that the environment of the horseshoe crab has
changed minimally? Yes. Natural selection of certain changes explains adaptations to
new environment.
4.
If a characteristic is found in bacteria, fungi, pine trees, snakes, and humans,
when did it most likely evolve? In Precambrian time. Why? Each organism inherited
the characteristic from a preexisting one.
5.
What are homologous structures, and what do they show about relatedness?
Homologous structures have similar anatomy because they are derived from a common
ancestor. Organisms are related when they have a common ancestor.
6.
Why do humans and chicks develop similarly to reptiles? They are related
through a common ancestor.
7.
What do DNA mutations have to do with amino acid changes in a protein?
Mutations are changes in DNA nucleotide base sequences and this sequence determines
the sequence of amino acids in a protein.
8.
How can antigen-antibody reactions help determine the degree of relatedness
between species in this laboratory?. The relatedness of an animal to humans was
judged by the degree to which they shared the same antigen-antibody reaction.
9.
Using plus (+) symbols, show the amount of reaction you would expect when
a pig, monkey, and chimpanzee are tested for the same human antibody-antigen
reaction. pig +, monkey ++, chimpanzee +++
10.
Define the following types of evidence for evolution:
Fossil: Any past evidence of an organism that has been preserved in the Earth’s
crust. Fossils show that organisms have changed (evolved) over time.
Common descent: Descent from a common ancestor. The concept of evolution is
based on common descent.
Adaptation: An organism’s modification in structure, function, or behavior
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suitable to the environment. Differences in adaptations support evolution.
Molecular evidence: Molecules found in organisms such as DNA and ATP.
Similarity of these molecules supports evolution.
7
Laboratory
13
Microbiology
(LM pages 143–61)
Fourth Edition
No significant changes have been made to this laboratory.
New Figures 13.6 Major Groups of Protists; 13.12 Protozoan diversity
MATERIALS AND PREPARATIONS
Instructions are grouped by exercise. Some materials may be used in more than one
exercise.
Special Requirements
Living material. Selected cultures of bacteria and protists (see lists below); incubate
cultures of bacteria 48 hours prior to use. Also incubate cultures of Rhizopus.
Fresh material. Pond water; edible mushrooms and other fresh fungi samples, if
available.
13.1 Bacteria (LM pages 144–49)
_____ safety goggles (See Carolina’s Safety: Face Protection Section)
_____ latex gloves and/or nonlatex gloves (See Carolina’s Safety: Hand Protection
Section)
_____ lab coats (See Carolina’s Safety: Body Protection Section) or other clothing
protection
_____ microscopes, compound light
_____ lens paper
_____ slides, prepared: bacteria (coccus, bacillus, spirillum)
_____ Oscillatoria, live culture or prepared slide
_____ Anabaena, live culture or prepared slide
_____ Gleocapsa, live culture or prepared slide
_____ bacteria, live cultures of representative types (Carolina’s “Living Organisms:
Bacteria Cultures” catalog section)
_____ nutrient agar plates
_____ incubator
Biohazard waste container. Because of increased awareness of hazards connected with
bodily fluids, a biohazard waste container for swab disposal should be used, and slides
8
and coverslips should be washed in a 10% bleach solution.
Prepared slides. Carolina Biological Supply Company has an immense variety of
prepared slides available. For prepared slides of bacteria, select representatives of
bacillus (rod-shaped), coccus (sphere-shaped), and spirillus (spiral-shaped) bacteria, as
well as prepared slides of Gloeocapsa, Oscillatoria, and Anabaena.
Agar plates. Ready-to-use nutrient agar plates (Carolina 821862) for the culture of
bacteria can be ordered. See the section of the Carolina Biological Supply catalog entitled
“Microbiological Media/Prepared Media Plates.” If you wish to prepare your own plates,
purchase nutrient agar and bacterial cultures (below). Prepare according to package
directions, and pour into sterile petri dishes.
Bacterial cultures. A variety of bacteria are available for live cultures. Choose
representative types from Carolina Biological Supply catalog’s “Living Organisms:
Bacteria Cultures” section. Inoculate the demonstration agar plates with the cultures
approximately 48 hours prior to use. Incubate in a warm incubator. After plate surfaces
are covered with the organism, store the plates in a refrigerator until use.
13.2 Protists (LM pages 149–56)
_____ slides and coverslips for live cultures
_____ microscopes, compound light
_____ microscopes, stereomicroscope
_____ lens paper
_____ Spirogyra, live culture or prepared slide
_____ Volvox, live culture or prepared slide
_____ slides, concavity
_____ diatoms, live culture or prepared slide
_____ Amoeba, Euglena, Paramecium, live cultures
_____ Protozoa Survey Set: Amoeba, Euglena, Paramecium, Stentor, Volvox, live
cultures
_____ For viewing live pond water organisms: Use fresh pond water; or any Pond
Mixture from a supply house,
_____ pond water for maintaining cultures
_____ pictorial guides to aquatic organisms (see Lab Manual Figure 13.14,
Microorganisms found in pond water, and above for other references)
Protist cultures. A variety of protozoans are available for live cultures. Choose
representative types from Carolina Biological Supply catalog’s “Living Organisms:
Protists” section.
13.3 Fungi (LM pages 157–60)
Black Bread Mold (LM pages 158–59)
_____ white bread, fresh (without preservatives), one loaf for approx. 200 students
_____ petri dishes (Carolina, see “Laboratory Equipment and Supplies: Dishes”)
_____ water, distilled
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_____
_____
_____
_____
_____
_____
_____
eyedropper
microscopes, stereomicroscope
microscopes, compound light
lens paper
Rhizopus, whole mount slide (including sexual stages) (Carolina 16 7776)
Basic Fungi Set, preserved
Fungi Collection biomount
Growth of Rhizopus on white bread in petri dish. Purchase white bread containing no
preservatives, since Rhizopus not likely to develop on bread containing preservatives.
Place a small amount of preservative-free white bread in the petri dish. Add one drop
only of distilled water. (Any more than one drop, and yeast growth will be promoted
instead of Rhizopus growth.) Sprinkle a small amount of dust from the corners of the
room on the bread. Rhizopus growth occurs within two to three days and is at its peak
within a week. Have students observe Rhizopus with a stereomicroscope. Rhizopus live
culture can also be purchased if desired
Club Fungi (LM pages 159–60)
_____ mushroom, edible, fresh
_____ microscopes, stereomicroscope
_____ microscopes, compound light
_____ slide, prepared: Coprinus mushroom, showing cross section of the cap
_____ lens paper
EXERCISE QUESTIONS
13.1 Bacteria (LM pages 144–49)
Pathogenic Bacteria (LM page 144-45)
Conclusions (LM page 145)
• Which portions of a bacterial cell aid the ability of a bacterium to cause
infections? cell wall, capsule, pili, and ribosomes, nucleoid, and plasmids through
the products they make
• Which portions of a bacterial cell aid the ability of a bacterium to be resistant to
antibiotics? pilli, cell membrane, capsule, ribosomes, plasmids
Observation: Colony Morphology (LM page 146)
2. Compare the colonies, color, surface, and margin and note your observations in
Table 13.1.
Table 13.1 Agar Plates
These data will depend on the bacteria used.
Experimental Procedure: Colony Morphology (LM page 146)
1. Describe what you see. These data will depend on student experiment.
2. Describe the appearance of your plate after exposure. These data will depend on
student experiment.
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Conclusions (LM page 146)
 What have you discovered from this exercise? Bacteria are present in the
environment most everywhere.
Observation: Shape of Bacterial Cell (LM page 147)
1. What magnification is required to view bacteria? 400× or oil emersion
2. Using Figure 13.2 as a guide identify the three different shapes of bacteria.
spiral, rod, and round
3. Do any of the slides on display show bacterial cells with endospores? depends on
slides
What is an endospore, and why does it have survival value? spore formed inside a
cell which can survive harsh treatment such as lack of water and severe temperatures
Observation: Cyanobacteria (LM page 147-49)
Gloeocapsa
2. What is the estimated size of a single cell? 1–3 µm
Oscillatoria
2. If you have a living culture, are oscillations visible? The answer will depend on the
sample used.
Anabaena (LM page 149)
2. If you have a living culture, what is its color? blue-green
13.2 Protists (LM pages 149-56)
Observation: Green Algae (LM pages 150–51)
1. How do you think Spirogyra got its name? chloroplast spirals
Volvox
2. In Table 13.2, list the genus names of each of the green algae specimens
available, and give a brief description.
Table 13.2 Green Algae Diversity
Answers will vary according to laboratory specimens.
Observation: Brown Algae and Red Algae (LM page 151-152)
In Table 13.3, list the genus names of each of the brown and red algae specimens
available, and give a brief description.
Table 13.3 Brown and Red Algae
Specimen Genus
Description
Answers will vary according to laboratory specimens.
Observation: Diatoms and Dinoflagellates LM pages 153)
Make a wet mount of live diatoms, or view a prepared slide (Fig. 13.10). Describe
11
what you see. Answers will vary according to student observation.
Prepare a wet mount of live dinoflagellates or view a prepared slide (Fig. 13.11).
Describe what you see. Answers will vary according to student observation.
Protozoans (LM pages 154-56)
How do sporozoans differ from other types of protozoans? Sporozoans do not
locomote.
Observation: Protozoans (LM page 155- 56)
1. Complete Table 13.4, listing the structures for locomotion in the types of
protozoans you have observed.
Table 13.4 Protozoans
Name
Structures for Locomotion
Observation
Answers will vary according to laboratory specimens.
2. Describe what you see. Student describes.
13.3 Fungi (LM pages 157–60)
Observation: Black Bread Mold (LM pages 158-59)
1. Do you recognize black bread mold on the bread? Answer will depend upon the
sample.
2. Label the mycelium and a sporangium in Figure 13.18a. 1. sporangium; 2. mycelium
3. Label the mycelium and zygospore in 13.18b. 1. zygospore; 2. mycelium
Club Fungi (LM pages 159-60)
Observation: Mushroom (LM page 160)
3. Can you see individual hyphae in the gills? It will depend upon the slide.
4. Are the basidiospores inside or outside of the basidia? outside
5. What type of nuclear division does the zygote undergo to produce the
basidiospores? meiosis
6. Can you suggest a reason for some of the basidia having fewer than four
basidiospores? Some of the basidiospores may have already been released.
7. What happens to the basidiospores after they are released? They usually give rise
to a mycelium.
LABORATORY REVIEW 13 (LM page 161)
1.
What role do bacteria and fungi play in ecosystem? They are both
decomposers.
2.
What type of semisolid medium is used to grow bacteria? Agar
3.
What is the scientific name for spherical bacteria? Cocci
4.
It is sometimes said that diatoms live in what kind of “houses”? glass
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5.
What type of nutrition do algae have? Photosynthetic
6.
Name a colonial alga studied today. Volvox
7.
Bacteria have what substance in their cell walls Peptidoglycan
8.
What color are Gram-negative bacteria following Gram staining? Pink
9.
Once called the blue-green algae, cyanobacteria are now classified as what?
Bacteria
10.
What do you call the projection that allows amoeboids to move and feed?
Pseudopod
11.
In what type of environment are you likely to find brown algae, such as
Fucus? Rocky seashore.
12.
The stalk and cap of a mushroom that rise above the substratum are termed
what? Fruiting body
13.
Describe saprotrophic nutrition? The organisms releases digestive enzymes into
the environment and absorbs the resulting nutrients.
14.
What do fungi produce during both sexual and asexual reproduction? Spores
15. Why aren’t all the organisms studied today in the domain Eukarya? Bacteria,
including cyanobacteria, are prokaryotes in the domain Bacteria. The other organisms
are eukaryotes in the domain Eukarya.
16.
In general, how does sexual reproduction differ from asexual reproduction
among fungi? During sexual reproduction, nuclei from two different mycelia fuse, and
zygote formation precedes meiosis, which is a part of spore formation.
13
Laboratory
14
Plant Evolution
(LM pages 163–180
Fourth Edition
The plant evolutionary tree has been updated and charophytes have been added to this
lab.
New/Revised Figures: 14.1 Evolution of plants.
Special Requirements
Living material. Moss gametophyte, moss sporophyte; assorted ferns for 14.2 Seedless
Plants. Living material. Pine cones, seeds, and needles for 14.3 seed plants.
Fresh material. Fresh flowers and fruits for 14.3 seed plants. Some flower shops,
especially wholesale shops, will make nonsaleable flowers available for educational
purposes.
MATERIALS AND PREPARATIONS
14.1 Evolution of Plants (p. 165-166)
_____ Chara, living
14.2 Seedless Plants (LM pages 167–71)
Mosses (LM page 167-68)
_____ moss gametophyte and sporophyte (optional) or moss life cycle
plastomount
_____ microscopes, compound light
_____ lens paper
_____ slide, prepared: moss antheridia and archegonia, whole mount (Carolina
29-8986)
Lycophytes (LM pages 169)
_____
club moss Lycopodium, living (Carolina) or preserved (Wards)
_____
slide, prepared: club moss (Lycopodium strobilus) (Wards)
Ferns (LM pages 170-71)
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_____ ferns, assorted living (see Carolina’s Plants: Living Organisms, Other
Ferns), or herbarium mounts (optional)
_____ fronds, with sori, living plastomount (optional)
_____ slide, prepared; fern frond leaflet with sori, cross section
_____ microscopes, compound light
_____ fern life cycle plastomount (optional)
_____ slide, prepared: fern prothallium-archegonia, whole mount
_____ slide, prepared: fern prothallium-antheridia, whole mount
14.3 Seed Plants (LM pages 172–179)
Gymnosperms (LM pages 173-175)
_____ pine cones, pollen and pine cone, seed (available from Carolina)
_____ Pine Life Cycle Set (optional)
_____ razor, single-edged
_____ microscope, binocular dissecting
_____ lens paper
_____ slide, prepared: mature pine male (staminate) cone, longitudinal section
_____ slide, prepared: pine seed (ovulate) cone, longitudinal section (available
from Carolina)
Life Cycle of Pine Trees (LM pages 174-75). Pine cones and seeds are available from
Carolina Biological Supply in the Pine Life Cycle Set (listed above). This set includes
cones from a variety of life cycle stages, as well as seeds, a seedling, and a twig with
needles. These are also available separately. See the “Preserved Plant” section of the
catalog. A collection of cones of various conifer species (Carolina 22-3320) is also
available. If possible, collect cones and needles from various local identifiable species for
display.
Angiosperms (LM pages 176-79)
_____ flower model
_____ flowers, fresh assortment of monocot and eudicot
_____ forceps or tweezers
_____ eye dropper
_____ slides and coverslips
_____ microscopes, compound light
_____ lens paper
_____ razor, single-edged
_____ water, tap
Fresh flowers (LM page 177-78). Obtain examples of monocot and eudicot flowers for
viewing and dissection. Some examples of monocots are tulips, hyacinths, and lilies.
Roses, geraniums, impatiens, and snapdragons are examples of eudicots.
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EXERCISE QUESTIONS
14.1 The Evolution Plants (LM pages 165–166)
What significant evolutionary events led to adaptation of plants to a land existence?
embryo protection, vascular tissue, megaphylls, seeds, flowers and fruit
Algal Ancestor of Land Plants (LM page165)
Observation: Chara
How does it superficially resemble a land plant? has a stem and branches Measure
the length of one cell. Cell can be as long as 7 cm What does it feel like? rough
Conclusions: Chara (LM page 165)
• What characteristics cause Chara to resemble land plants? appearance, protects
zygote
• Why are Chara called stoneworts? covered with calcium carbonate deposits
Alternation of Generations (LM page 166)
Is it beneficial for a sporophyte, the generation that has vascular tissue, to be
dominant? Yes Why? Without the transport of water, a plant has to remain lowlying.
14.2 Seedless Plants (LM pages 167-71)
Mosses (LM pages 167--68)
Life Cycle of Mosses (168)
Describe its appearance. It is a stemlike structure covered with whorls of leaflike
structures. Considering that this is the generation we refer to as the “moss,” what
generation is dominant in mosses? Gametophyte Describe the sporophyte. The
sporophyte is a stalk attached to the gametophyte, topped by a capsule that contains a
sporangium.
Observation: Moss Life Cycle (LM page 168)
2.
Why female? Because the female gametophyte is dominant.
3.
What is being produced in the sporangium? Spores By what process? Meiosis
The Life Cycle of a Moss (LM page 168)
1.
Which generation is haploid? Gametophyte Which is diploid? Sporophyte
Which generation is dominant in mosses? Gametophyte Which generation is
dependent? Sporophyte
2.
Is there any evidence of vascular tissue in the moss sporophyte? No
3.
When spores germinate, what generation begins to develop? Haploid
gametophyte
4.
Why is it proper to say that, in the moss, spores disperse the plant? Only
spores leave the plant.
5.
By what means are spores disseminated? Wind
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Adaptation of Mosses to the Land Environment (LM page 168)
Which of these is an indication that mosses are well adapted to life on land?
Lack of vascular tissue no
Flagellated sperm no
Body covered by a cuticle that prevents drying out yes
Egg and embryo protected by female shoot yes
Spores are windblown yes
Ferns (LM pages 170-71)
Observation: Fern Life Cycle (LM page 170-71)
1.
What is being produced in the sporangia? Spores Considering that it is this
generation that we call the fern, what generation is dominant in ferns? Sporophyte
3.
What is the function of the gametophyte? To produce gametes.
4.
What is being produced inside the archegonium? Egg
5.
What is being produced inside the antheridia? Sperm When sperm produced
by the antheridia swim to the archegonia in a film of water, what
results? Fertilization occurs, resulting in a zygote. The latter develops into what
generation? sporophyte (on the existing gametophyte)
The Life Cycle of a Fern (LM page 171)
1.
Which generation in the fern dependent for any length of time on the other
generation? neither generation is dependent on the other
2.
Which generation is dispersed in ferns? gametophyte How? windblown spores
Adaptation of Ferns to a Land Environment (LM page 171)
State a significant way in which the fern is adapted to life on land, when you
compare it to the moss. They have vascular tissue.
List one characteristic of the fern illustrating that sexual reproduction is not
adapted to a land environment. The gametophyte produces flagellated sperm.
14.3 Seed Plants (LM pages 172-179)
1. Seeds plants have two dispersal events. These events are dispersal of pollen grains
and dispersal of seeds.
2. During dispersal of seeds, what generation is dispersed to a new location?
sporophyte
Gymnosperms (LM pages 173-75)
Life Cycle of Pine Trees (LM pages 174-75)
Describe the sporophyte in the life cycle of the pine tree. The sporophyte is a tree that
that produces cones.
Observation: Pine Cones (LM pages 174-175)
2.
Label Figure 14.13. Pollen grains
3.
Examine the prepared slide of a longitudinal section through a seed cone and
label Figure 14.14. a. winged pollen grain b. ovule c. egg What generation is now
within the ovule? Female gametophyte
17
Angiosperms (LM pages 176-79)
Life Cycle of Flowering Plants (LM pages 176-178)
Describe the sporophyte if the flowering plant is a deciduous tree. The sporophyte is
the deciduous tree.
Describe the sporophyte of a garden plant. The sporophyte is the garden plant.
Observation: Flower (LM pages 177-78)
2.
Are the stamens taller than the carpel? Most likely, the stamens will be taller.
Would self-fertilization be possible in this flower? Yes, if the stamens are taller than
the carpel.
3.
How is pollen dispersed? Windblown or carried by animals What does a
pollinator do for a plant? Carries pollen from stamen to carpel.
4.
Do you see cells within the ovule? Most likely
5.
Which portion of each should be associated with the ovules? The seed in the
apple and the pea in the pea pod. Which with the ovary? The apple flesh in the apple
and the pea pod.
Label flower remnants, fruit, and seed in the following diagram. Apple: 1. Seed, 2.
Fruit; 3. Flower remnant; Pea pod: 1. Flower remnant; 2. Fruit; 3. Seed
Can you think of a biological advantage to producing fruits? Added protection
against drying out. To producing a fleshy fruit? Animals eat the fruit and aid in
dispersing the seed.
Compare the Life Cycle of a Pine Tree to That of a Flowering Plant (LM page 179)
Complete the following table:
Dominant
Generation
Vascular
Tissue
Dispersal of
Sporophyte
Fruit
Conifer
sporophyte
present
wind-blown
absent
Flowering plant
sporophyte
present
wind or
pollinator
present
Adaptation of Seed Plants to a Land Environment (LM page 179)1.
Do seed
plants have vascular tissue, which transports water and nutrients to all parts of the
plant? Yes.2. Can seed plants support a large body against the pull of gravity? Yes.
The vascular tissue serves as an internal skeleton opposing the force of gravity
3.
Do seed plants reproduce without dependence on external water? Yes.
Pollination does away with the need of water for fertilization.
Comparison of Moss, Fern, Pine, and Flowering Plants (LM page 179)
18
1.
The preceding diagram tells you that the size of the gametophyte became
progressively smaller as plants became adapted to live on land. Why is it suitable for
this generation to be dependent on the sporophyte? The gametophyte lacks vascular
tissue.
2.
Which plants disperse spores? Mosses and ferns
3.
Which plants have male and female gametophytes and disperse seeds?
Gymnosperms
4.
Why is it appropriate to refer to “bees and plants” to explain sexual
reproduction? Bees take pollen (the male gametophyte, which produce sperm) to the
female gametophyte, which produces an egg. Union of sperm and egg results in a zygote,
which becomes on embryo in a seed.
LABORATORY REVIEW 14 (LM page180)
1. Name one way that each type plant shows an adaptation to the land environment
not seen before:
a. Moss wind-blown spores
b. Lycophyte vascular tissue
c. Fern megaphylls
d. Pine tree seeds
e. Flowering plant pollination by animals
2. The gametophyte is not protected in which of the plants listed in question 1? a,b,c
3. In what way do flowering plants protect the female gametophyte? stays within
ovule
The male gametophyte? pollen grain has a hard covering
4. In the flowering plant life cycle
a. What becomes of the ovule? becomes seed
b. What becomes of the ovary? becomes fruit
5. Windblown spores are an adaptation to the land environment in which three
types of plants studied in this laboratory? moss, lycophyte, fern
6. Why is it beneficial to have the sporophyte dominant in plants adapted to the land
environment? Sporophyte has vascular tissue.
7. Which generation is in a seed? sporophyte
8. Why are flagellated sperm a drawback in plants that live on land? Flagellated
sperm need moisture to swim to egg.
19
9. When does meiosis occur in the life cycle of plants? production of haploid spores
10. What type of cell division produces the gametophyte generation and the gametes
in plants? Mitosis
20
Laboratory
15
Plant Anatomy and Growth
(LM pages 181- 92)
Fourth Edition
This lab remains as it was in the previous edition.
MATERIALS AND PREPARATIONS
Special Requirements
Fresh material. Tomato or geranium plant for Observation: A Living Plant; winter twig
for Observation: Anatomy of Winter Twig. Obtain locally if possible, close to time of
use.
15.1 Plant Organs (LM pages 182-83)
_____ tomato or geranium plant, living
(obtain locally if in season)
_____ representative monocot and eudicot
leaf types for display (fresh or
herbarium mounts)
15.2 Organization of Roots (LM pages 184-85)
_____ model, root tip or eudicot root tip slide
_____ seedlings, germinated
_____ petri dishes
_____ stereomicroscopes
_____ 0.1% neutral red (Carolina 87-6853, -6855)
15.3 Xylem Transport (LM page 186)
Experimental Procedure: Xylem Transport (LM page 186)
_____ red food coloring
_____ beakers or glass jars
_____ celery, fresh
_____ scissors
_____ eye dropper
_____ slides and coverslips
_____ steromicroscope
21
15.4 Organization of Stems (LM pages 187–89)
_____slide, prepared, eudicot: Helianthus (sunflower) stem, cross section
_____slide, prepared, monocot: Zea mays (corn) stem, cross section
_____winter twigs, collected or purchased
_____slide, prepared, eudicot woody stem: Tilia (tulip tree/basswood) stem, cross
section
15.5 Organization of Leaves (LM pages 190–91)
_____ fresh leaf, from jade plant or begonia (for observation of stomata)
_____ forceps
_____ slide, prepared, leaf: Ligustrum (common privet),
Leaf types. Representative leaf types are simple, compound, palmately or pinnately
compound, palmately or pinnately veined, and parallel veined. Collect a variety of fresh
leaf types, or use a leaf types set, which shows twelve specimens on a single herbarium
mount.
EXERCISE QUESTIONS
15.1 Plant Organs (LM pages 182–83)
Observation: A Living Plant (LM page 182)
Shoot System
What is the primary function of the shoot system? Photosynthesis, and transport of
water and nutrients
The Leaves
1
Describe the blade. the broad, flat part of a leaf
2
Describe the petiole. a stalk that attaches the blade to the stem
The Stem 2 Does the internode get larger or smaller toward the apex of the
stem? smaller Toward the roots? larger Based on the fact that a stem elongates as
it grows, explain your observation. Elongation causes length of internode to increase
as plant grows.
3.
Where is the terminal bud of a stem? at the apex of a shoot Where is the
lateral bud? on the side of the shoot.
Root System
Does the plant have a tap root system—that is, the main root many times larger
than the lateral roots? Answer will vary with plant observed
Or does the plant have a fibrous root system—that is, all the roots
approximately the same size? Answer will vary with plant observed. What is the
primary function of the root system? Anchor plant and absorption of water and
minerals
Experimental Procedure: Monocot Versus Eudicot (LM page 183)
1. Is this plant a monocot or dicot? Depends on plant observed. Explain. Answer should
make use of information in Figure 15.2.
22
2. Note in Table15.1 name of plant and whether it is a monocot or dicot: Answers will
vary depending on types of plants used.
15.2 Organization of Roots (LM pages 184-85)
Observation: Eudicot Root Tip
2.
Identify: Root cap. What is the function of the root cap? protection
Zone of elongation. Which two zones are responsible for growth of the root tip?
zone of cell division and zone of elongation
Zone of maturation. Root hairs increase the area for absorption of what by a root?
water and minerals
Observation: Eudicot Root Slide (LM page 185)
2.
Identify: Cortex. How many layers of thin-walled cells are present? Several.
Answer will depend on the slide observed. Label starch grains in Figure 15.4b. The starch
grains are the blue-stained areas of cells located in the cortex.
3.
Trace the path of water as it crosses a root from a root hair to xylem: root
hair, cortex, endodermis, per-icycle, xylem
Observation: Root Hairs (LM page 185)
2.
What proportion of the root has root hairs? Answer will vary.
4.
Does every epidermal cell have a root hair? No. How do root hairs aid
absorption? The large number of root hairs on a root provide increased surface area for
absorption.
15.3 Xylem Transport (LM page 186)
Experimental Procedure: Xylem Transport (LM page 186)
6.
In which celery stalk was the water column broken? The water column was
broken in the stalk that was cut and kept in air prior to experiment.
Use this information to write a conclusion in Table 15.2.
7.
What type of tissue has been stained by the dye? xylem
Table 15.2 Celery Stalk Experiment
Speed of Dye
Stalk
(Minutes)
Placed in Water
Placed in Air
Faster
Slower
Conclusion
Water column was not broken
Water column was broken
15.4 Organization of Stems (LM pages 187–89)
Observation: Anatomy of Eudicot and Monocot Herbaceous Stems (LM page 187)
3. State the difference between the eudicot stem and the monocot stem. In the
eudicot stem the vascular bundles are arranged in a ring, while in the monocot
stem they are scattered.
Observation: Anatomy of a Winter Twig (LM page 188)
5. Note the vascular bundle scars. Complete this sentence: Vascular bundle scars
appear where the vascular bundles previously extended into leaf petioles or a
branch that dropped off.
23
Observation: Anatomy of Woody Stem (LM pages 189)
3. How old is the stem you are observing? Answer depends on the stem examined.
Are all the rings the same width? not likely
15.5 Organization of Leaves (LM page 190–91)
Observation: Stomata (LM page 190)
4.
What gas enters a leaf at the stomata? CO2
5.
Count the number of stomata in the high-power field of view: example: six
stomata
6.
Divide the number of stomata by this area to determine the number of
2
stomata in 1 square millimeter: example: 6 (stomata) divided by 0.10 mm = 60
2
stomata/mm
7.
Does your leaf contain a large number of stomata per square millimeter?
Answers will vary.
Observation: Leaves (LM page 191)
2. What tissue does a leaf vein contain? vascular (xylem and phloem) Label the
palisade mesophyll in Figure 15.10. Label the spongy mesophyll in Figure 15.10.
Which type of mesophyll has chloroplasts? spongy and palisade mesophyll
Which type of mesophyll carries on photosynthesis? spongy and palisade
mesophyll Which type of mesophyll has air spaces that facilitate exchange of
gases? spongy mesophyll
Figure 15.10: 1. palisade mesophyll; 2. spongy mesophyll
LABORATORY REVIEW 15 (LM page 192)
1.
Given the information in this laboratory, how would you distinguish between
a monocot plant and a eudicot plant based on their external anatomy? The leaves of
a monocot plant have parallel veins, while the leaves of a eudicot plant have a net vein
pattern.
2.
What is meristem tissue? Meristem is embryonic tissue. How is this tissue
different from all other types of plant tissue? It continually produces new cells. This
accounts for plants’ ability to grow their entire lives.
3.
In which zone of a eudicot root would you expect to find vascular tissue?
Why? Vascular tissue is found in the zone of maturation because cells become
specialized in this zone.
4.
In a eudicot root, what structural feature allows the endodermis to regulate
the entrance of water and materials into the vascular cylinder, where xylem and
phloem are located? The Casparian strip, a layer of waxy material, prevents the
passage of water and materials between root cells so that they must pass through the
endodermis.
24
5.
Characterize the root of a carrot. The taproot is modified for the storage of
organic food. The main root is many times larger than the branch roots.
6.
How would you microscopically distinguish a eudicot stem from a monocot
stem? In a eudicot stem, the vascular bundles are arranged in a ring; in a monocot stem,
they are scattered.
7.
Distinguish between primary and secondary growth of a stem, and explain
how each arises. Primary growth arises from the apical meristem in the terminal bud
and adds to the length of a plant. Secondary growth arises from vascular cambium and
adds to the girth of a plant.
8.
Contrast how you could determine one year’s growth by looking at a winter
twig with how you determine one year’s growth in a cross section of a tree stem. In a
cross section of a tree, one annual ring indicates one year’s growth. In a woody twig, the
growth between terminal bud scars represents one year’s growth.
9.
Contrast the manner in which water reaches the inside of a leaf with the
manner in which carbon dioxide reaches the inside of a leaf. Water enters xylem at the
roots and then passes up the stem to a leaf vein. Carbon dioxide enters by way of stomata
into the cells of spongy mesophyll.
10.
How would you recognize the epidermis of a root versus the epidermis of a
leaf? The leaf epidermis has an upper and lower section and is covered with a cuticle to
protect its layers. The root epidermis has no protection and has root hairs for water and
nutrient absorption.
25
Laboratory
16
Animal Evolution
(LM pages 193–209)
Fourth Edition
The animal evolutionary tree has been updated
New/Revised Figures: 16.1 Evolution of animals.
MATERIALS AND PREPARATIONS
Special Requirements
Preserved Specimens. Preserved clams, squid, crayfish, and grasshopper, are required
for this lab. Diverse molluscs and arthropods are to be examined by students, as are
examples of incomplete and complete metamorphosis.
All Exercises
_____ dissecting pans, pins, tools, and trays
_____ safety goggles
_____latex gloves and/or non-latex gloves
_____ lab coats
16.2 Invertebrates (LM pages 194–206)
_____ mollusc collection
_____ clam, Venus, preserved for dissection
______ squid, preserved
_____ arthropod collection
_____ crayfish, preserved
_____ grasshopper, Romalea, preserved
_____ hand lenses
_____ index cards
_____ stereomicroscopes
_____ lens paper
_____ life cycle display showing incomplete and complete metamorphosis.
EXERCISE QUESTIONS
16.1 Evolution of Animals (LM page 194)
26
Which phyla in the tree have only two tissue layers? cnidarians
Which of the phyla have radial symmetry? cnidarians
Which pattern of development do the flatworms, rotifers, and nematodes have?
protostome
16.2 Invertebrates (LM pages 195–206)
Observation: Diversity of Molluscs (LM pages 195–200)
Table 16.1 Molluscan Diversity*
Common
Group
Description of Foot
Name
of Specimen
Broad, flat, for
Chiton
Chitons
creeping
Broad, flat, for
Oyster drill
Gastropod
creeping
Scallop
Bivalve
Hatchet-shaped
Squid
Cephalopod Divided into tentacles
Cephalization
(Yes or No)
No
Yes
No
Yes
*Answers will vary, depending on specimens provided. Examples are given.
Anatomy of Clam (LM Pages 196–98)
External Anatomy (LM page 196)
4.
What is the function of a heavy shell? protection
Internal Anatomy (LM page 197-198)
1. What is a mantle? The mantle is a covering that partly covers the visceral mass
and secretes the shell.
3. What is the advantage of powerful adductor muscles? They keep the two shells
closed for protection.
6. Explain the term mantle cavity. The mantle cavity is the space between the folds of
the mantle.
7. Explain how water enters and exits the mantle cavity. Water enters through the
incurrent siphon, circulates through the mantle cavity, then exits through the excurrent
siphon.
8. Does the clam have a respiratory organ? yes What type of respiratory organ? It
has gills.
9. Why is the clam called a filter feeder? Only small particles of food can enter the
siphon and be directed toward the mouth, large particles remain outside the body of a
clam.
15. A clam has an open circulatory system. Explain. The blood is not always enclosed
in vessels.
27
Anatomy of Squid (LM Pages199–200)
Clam Anatomy Compared with Squid Anatomy (LM page 199)
2. Explain how both clams and squids are adapted to their way of life. Clams are
inactive filter feeders. They have no cephalization and are protected by a shell.
Squids are active predators. They have tentacles and jaws to seize and tear apart
prey. They lack a shell but have cephalization with eyes and a well-developed brain.
An ability to move by jet propulsion helps squids escape from predators.
Table 16.2 Comparison of Clam to Squid
Clam
Feeding mode
Filter feeder
Skeleton
Heavy shell for protection
Circulation
Open
Cephalization
None
Locomotion
Hatchet-shaped foot
Nervous system
Three separate ganglia
Squid
Active predator
No external skeleton
Closed
Marked
Jet propulsion
Brain and nerves
Arthropods (LM page 201)
Arthropods are segmented like the annelids, but specialization of segments has
occurred. Explain. The segments have fused into regions, such as head, thorax, and
abdomen. Each region has specialized appendages (mouthparts, antennae, legs, and
wing)s. Legs are attached to the thorax.
Observation: Diversity of Arthropods (LM page 201)
Examine various specimens of arthropods and complete Table 16.3. In the last column,
note the number of legs attached to the thorax
Table 16.3 Arthropod Diversity*
Common Name
Group
of Specimen
arachnid
Garden spider
crustacean
Crayfish
insect
Grasshopper
Centipede
centipede
Millipede
milipede
Appendages
(Attached to Body)
four pairs of legs
five pairs of legs
three pairs of legs
one pair of legs per
segment
two pairs of legs per
segment
*Answers will vary, depending on specimens provided. Examples are given.
Anatomy of Crayfish (LM pages 202-03)
External Anatomy (LM pages 202)
2.
Has specialization of segments occurred? yes Explain. Segments have fused,
28
forming specific regions, and there are specialized appendages on various segments.
4.
Do crayfish demonstrate cephalization? yes Explain. There is a distinct head
region, although it may be fused with the thorax.
7.
8.
What sex is your specimen? Answers will vary.
Has specialization of appendages occurred? yes Explain. The appendages have
specialized functions, such as walking, swimming, reproduction, and feeding.
Anatomy of Grasshopper (LM pages 203-205)
External Anatomy (LM page 204)
2.
How many pairs of legs are there? three pairs
3.
Is locomotion in the grasshopper adapted to land? yes Explain. The
grasshopper has jointed legs for crawling and jumping on land and wings for flying in
air.
6.
Why is this beneficial? Insects need energy to fly and the oxygen is used by
mitochondria to produce ATP.
Internal Anatomy (LM page 204)
What is the function of Malpighian tubules? Excretion of nitrogenous waste.
Conclusion (LM pages 204)
Put a star beside each item (in Table 16.4) that indicates an adaptation to life in the
water (crayfish) and to life on land (grasshopper). How many did you identify? They
should have identified eight.
Table 16.4 Comparison of Crayfish to Grasshopper
Crayfish
Locomotion
*Legs and swimmerets
Respiration
*Gills
Sense organs
Antennae, compound eyes
Nervous system
External reproductive
features
Male
Female
Cephalization
Grasshopper
*Jumping legs, wings
*Tracheae, *spiracles
Antennae, compound eyes,
*tympanum
Cephalization
*Modified swimmerets
_____
*Claspers and penis
*Ovipositor Insect
*Adaptation to water for crayfish/ to land for grasshopper
Observation: Insect Metamorphosis (LM page 206)
Name a type of insect that undergoes complete metamorphosis. True bugs such as
leafhopper
29
Name a type of insect that undergoes incomplete metamorphosis. Flies such as fruit
flies
16.3 Vertebrates (LM page 207-208)
Explain the term invertebrate chordates. These chordates retain the notochord and do
not have a vertebral column.
What three innovations called out in Figure 18.16 evolved among fishes? jaws, bony
skeleton, and lungs
The limbs of tetrapods are jointed appendages. Do all animals develop in a water
environment? Yes. Explain. The reptiles including birds and mammals develop within
the aminotic membrane, which contains aminotic fluid.
LABORATORY REVIEW 16 (LM page 209)
.
1. Name two types of organisms (not dissected) that belong to each of these phyla:
a. Mollusca scallop and snail
b. Annelida roundworms such as earthworms and leaches (see textbook)
c. Arthropoda spider and barnacle
d. Ecinoderms sea stars and sea urchins (see textbook)
e. Chordata fish and snake
2. Name the type of foot and location of the foot in a clam and squid. Clam has a
hatchet foot that projects from shell and a squid has tentacles and arms that circle
the mouth.
3. Associate the type of foot in a clam and squid with their way of life. Clams dig in
sandy soil for food and squid swims rapidly to catch prey with tentacles and arms.
4. Both externally and internally, earthworms show evidence of segmentation. How?
Externally you can see segments and internally each segment has organs, e.g.,
nephridia (see textbook)
5. Name one obvious adaptation of a crayfish and one adaptation of a grasshopper
to their environment. Crayfish have claws for catching prey in water, grasshopper
has mouthparts for eating grass.
6. How do insects assist the transport of oxygen to flight muscles? They have trachaea.
7. How do you know that the grasshopper adaptation you provided in question 5 is
an adaptation to life on land? Trachea are air tubes.
8. What system is unique to echinoderms and what is its function? The water
vascular system expands tube feet that are used in locomotion.
9. What innovation during the course of evolution can you properly associate with
30
these classes of vertebrates?
a. Ray-finned fishes bony skeleton
b. Amphibians 4 limbs
c. Reptiles amniotic egg
10. What type of skeleton do both arthropods and vertebrates share? jointed
exoskeleton
31
Laboratory
17
Basic Mammalian Anatomy I
(LM pages 211–24)
Fourth Edition
No significant changes have been made to this laboratory. However this lab now precedes
Chemical Aspects of Digestion. This change of organization allows students to be
introduced to the digestive system before studying chemical digestion in particular. The
lab offers alternatives; students may follow the directions to 1) dissect the pigs alone or
in a group 2) observe dissected pigs or 3) study the illustrations and answer the questions
only.
Notes:Dissecting tools. As an alternative to a complete set of dissecting tools, two sizes
of sharp scissors, forceps, and blunt probes can be used. Scalpels can be kept at the
instructor’s bench to be used at the instructor’s discretion.
Safety. Fetal pigs are sometimes preserved by using formalin. Safety goggles, latex or
nitrile gloves, and lab coats or other clothing protection are recommended.
MATERIALS AND PREPARATIONS
Instructions are grouped by exercise. Some materials may be used in more than one
exercise.
Special Requirements
Preserved Specimens. Preserved fetal pigs are required for this lab. Note: In this
laboratory, do not remove any organs. Laboratory 20, Basic Mammalian Anatomy II,
contains exercises for dissecting the organs of the urinary system, the male and female
reproductive systems, the respiratory and digestive systems, and the cardiovascular
system.
17.1–17.6
_____
_____
_____
_____
_____
_____
All Dissection Exercises (LM pages 212–22)
safety goggles
latex gloves and/or nonlatex gloves
lab coats or other clothing protection
fetal pigs, preserved, for dissection
dissecting pans, pins, tools, and trays
glass medicine droppers (for suctioning off excess fluids) or
polystyrene disposable pipets
32
_____
_____
_____
_____
labels, for labeling individual pigs
“pig dip” bucket containing preservative (or preservative in spray bottles)
string, heavy, for tying pigs into dissection pans and for tying bags
plastic bags or containers for storing pigs
Fetal pigs. Fetal pigs for dissection are available from many supply houses. Large,
double-injected specimens are recommended. You may wish to soak the pigs in water
overnight to decrease the smell and concentration of preservatives to which students and
instructors are exposed. Before placing pigs into the plastic storage bags, have students
pick them up by strings tied around the pigs’ hind legs. Dip pigs in a “pig dip” bucket
containing preservative. Alternatively, spray pigs with preservative from a spray bottle
before storing.
17.7
Human Anatomy (LM page 223)
_____ model, human torso
Human torso model (LM page 223). Human torso models are available from a number
of supply houses. The Carolina Biological Supply Company has a variety of torso models
that vary widely in price. See Carolina’s “Models” section.
EXERCISE QUESTIONS
17.1 External Anatomy (LM pages 212–14)
Observation: External Anatomy
Body Regions and Limbs
5. Where is the heel of the pig? raised up, off the ground
Umbilical Cord
3. What is the function of the umbilical cord? It contains the umbilical blood vessels
that take blood to the placenta, where fetal blood gives up waste and receives oxygen
and nutrients.
Nipples and Hair
1. How many nipples does a pig have? Both males and female pigs have 16 nipples.
When is it advantageous for a pig to have so many nipples? A nursing mother can
suckle many offspring.
2. Can you find hair on the pig? yes Where? on the eyelashes and on the chin
Anus and External Genitals (LM page 213)
1. Name the organ system which ends in the opening called the anus? digestive
system
4. What sex is the sex of the pig you are examining? Figure 17.1b and c will aid in
distinguishing the sex of the pig?
17.2 Oral Cavity and Pharynx (LM pages 214–15)
Pharynx (LM page 215)
6. Explain why it is correct to say that the air and food passages cross in the
pharynx. Air must pass from the back to the front of the pharynx to enter the trachea,
and food must pass from the front to the back of the pharynx to enter the esophagus.
33
17.3 Thoracic and Abdominal Incisions (LM pages 216–17)
Thoracic Incisions
3. List the organs you find in the thoracic cavity. The heart and lungs are readily
apparent.
Complete Preparation of Pig for Dissection (LM page 216)
Answer These Questions
1. Name the two cavities separated by the diaphragm? the thoracic and abdominal
cavities
2. List the organs located in the abdominal cavity. The liver and intestines are readily
apparent.
17.5 Thoracic Cavity (LM pages 218–19)
Observation: Thoracic Cavity
Heart and Lungs
3. Trace the path of air from the nasal passages to the lungs. nasal passages,
pharynx, glottis, larynx, trachea, bronchi, lungs
17.6 Abdominal Cavity (LM pages 220–22)
Liver (LM 270)
3. Name several functions of the liver. destroying red blood cells, producing bile,
storing glycogen, maintaining blood glucose levels, producing blood proteins
Stomach and Spleen
4. The stomach is a part of the digestive system. What is its function? stores food,
secretes gastric juice, contains an enzyme for protein digestion
5. The spleen is a part of the lymphatic system. What is its function? purifies blood
and disposes of worn-out red blood cells
Small Intestine (LM page 222)
3. The small intestine is a part of the digestive system. What is its function? food
digestion and absorption of the products of digestion
Gallbladder and Pancreas
3. What is the function of the gallbladder? stores and releases bile
4. What is the function of the pancreas? As an exocrine gland it secretes pancreatic
juice; as an endocrine gland it secretes insulin and glucagon.
Large Intestine
4. The large intestine is a part of the digestive system.
5. What is the function of the large intestine? absorbs water, prepares feces for
defecation
6. Trace the path of food from the mouth to the anus. mouth, pharynx, esophagus,
stomach, small intestine, large intestine (colon and rectum), anus
17.7 Human Anatomy (LM pages 223)
Observation: Human Torso
2. Name any observed differences between pig internal anatomy and human internal
anatomy? no observed differences are expected.
34
LABORATORY REVIEW 17 (LM page 224)
1. What two features indicate that a pig is a mammal? mammary glands and hair
2. Put the following organs in logical order: lungs, nasal passages, nasopharynx,
trachea, bronchi, glottis. A logical order would be: nasal passages, nasopharynx, glottis,
trachea, bronchi, lungs.
3. What difficulty would probably arise if a person were born without an epiglottis?
When the individual swallows, food would enter the trachea.
4. What two cavities studied in this laboratory hold the internal organs? the thoracic
and abdominal cavities
5. Name two principal organs in the thoracic cavity, and give a function for each.
The heart pumps blood, while the lungs exchange gases.
6. What difficulty would arise if a person were born without a thymus gland? The
person’s immunity would be reduced, and his or her susceptibility to infections would
rise.
7. Name the largest organ in the abdominal cavity and list several functions. Liver.
The liver removes poisonous substances from the blood, detoxifies them, and removes
vitamins from the blood, which stores them. The liver makes plasma proteins and
regulates the cholesterol and glucose level of the blood. The liver also produces bile,
which aids digestion.
8. A large portion of the abdominal cavity is taken up with digestive organs. What
are they? The digestive organs are the stomach, the small intestine, and the large
intestine. The large intestine includes the cecum, colon, rectum, and anal canal.
9. Why is it proper to associate the gallbladder with the liver? The gallbladder is
located on the underside of the liver and stores bile made in the liver.
10. Where would you find the pancreas? The pancreas is dorsal to the stomach in the
upper left of the abdominal cavity.
35
Laboratory
18
Chemical Aspects of Digestion
(LM pages 225-34)
Fourth Edition
With the addition of Figure 18.1, which gives an overview of the organs of digestion, this
laboratory now provides a better correlation between digestion of foods and the digestive
tract of humans. The Experimental Procedure: Starch Digestion by Pancreatic Amylase
was streamlined by eliminating the two samples containing boiled enzyme.
New/Revised Figures 18.1 Organs of the digestive tract and accessory organs
MATERIALS AND PREPARATIONS
Special Requirements
Equipment. An incubator is required for Sections 18.1 and 18.2. Start these exercises at
the beginning of the lab. In Section 18.1 protein digestion requires a 1 ½
-hour incubation period; in Section 21.2 fat digestion requires incubation and
monitoring at 20-minute intervals. To save time, and ensure digestion you may wish to
perform the experiment prior to the lab and demonstrate the results of the experiments.
The fat digestion tubes can be incubated overnight to ensure digestion occurring.
Enzyme solutions. For the best results, make each section’s enzyme solutions fresh, with
no granules, just prior to the lab. However, if solutions must be made ahead of time,
make them up as close as possible to the time of use and refrigerate. If incubation is then
called for, warm the solution to room temperature in a water bath before incubating. To
make a 1% enzyme solution, dissolve 1 g of the enzyme powder in 100 mL of distilled
water.
All Exercises
_____
_____
_____
_____
_____
_____
_____
_____
18.1
safety goggles
latex gloves and/or non-latex gloves
lab coats
wax pencils
test tubes and racks
water, distilled
thermometer, celsius (0–110°C)
transfer pipets
Protein Digestion by Pepsin (LM pages 227-28)
_____ 1% albumin solution
36
_____
_____
_____
_____
1–2% pepsin solution
0.2% hydrochloric acid (HCl)
incubator, 37°C
biuret reagent
Order solutions or prepare your own:
Albumin solution (LM page 227). Prepare 10 mL per student group. Mix in a pH 7
buffer solution as per directions on the vial, and dissolve 1 g per 100 mL of water. Allow
time for precipitation to occur, and then decant. Swirl the stock prior to distribution to
students. Also, check pH with indicator paper, and adjust to pH 7 with dilute acid or base.
1–2% pepsin solution. Prepare 20 mL per student group as close to time of lab as
possible. To make a 1% solution, dissolve 1 g of pepsin in 100 mL of distilled water.
Refrigerate between labs but then warm student tubes to room temperature in a warm, not
hot, water bath.
0.2% hydrochloric acid (HCl) Add 0.57 mL of concentrated HCl to
100 mL of distilled water.
Biuret reagent. 30 mL per student group should be sufficient (using standard test tubes
for all procedures). If you buy prepared biuret, use only ten to fifteen drops; otherwise,
the solution will be too dark, or dilute to a 10% solution (10 mL biuret with 90 mL
distilled water). To prepare your own biuret reagent, maintain separate stock solutions of
3% copper sulfate—3 g of copper sulfate (cupric sulfate, Carolina 85-6550) per 100 mL
of distilled water and 10% potassium hydroxide or sodium hydroxide—100 g of
potassium hydroxide (Carolina 88-3488) or sodium hydroxide pellets (Carolina 88-9470)
per 1,000 mL of distilled water). Adding five drops of copper sulfate solution and ten
drops of potassium hydroxide solution to each experimental tube produces more
consistent results. Biuret reagent should be prepared fresh for each lab.
18.2
Fat Digestion by Pancreatic Lipase (LM pages 229-30)
_____ vegetable oil, preferably canola, olive, or sunflower
_____ phenol red solution
_____ pancreatin (pancreatic lipase)
_____ bile salts (Wards Biology 38W2179). One gram is enough for a class.
_____ incubator, 37°C
Students should not vigorously shake tubes (LM page 230). Oil will float above
phenol red solution and pancreatic lipase solution, and a color change may be observed in
the transition zone; however, it will not be uniform unless bile salts are added.
Order solutions or prepare your own:
Phenol red solution (LM page 230). Prepare 20 mL per student group. Use a 0.04%
solution. Dissolve 0.04 g of phenol red in 100 mL of distilled water.
Pancreatic lipase solution (1% pancreatin in 0.1% Na2CO3). Prepare 30 mL per
student group. As close to time of lab as possible, add 1 g pancreatin to every 100 mL of
0.1% Na2CO3 (0.1 g Na2CO3 per 100 mL of distilled water). Refrigerate between labs but
then warm student tubes to room temperature in a warm, not hot, water bath.
37
18.3
Starch Digestion by Salivary Amylase (LM page 231-232)
_____ pancreatic-amylase solution
_____ starch suspension
_____ boiling water bath
_____ test-tube holder
_____ hot plate
_____ beaker
_____ beaker tongs
_____ iodine-potassium-iodide (IKI) solution, premade
_____ Benedict’s reagent powder or Benedict’s reagent
solution
Order solutions or prepare your own:
Pancreatic-amylase solution (LM page 231). Prepare 20 mL per student group as close
to time of lab as possible. Dissolve 1 g pancreatic-amylase in 100 mL distilled water.
Refrigerate between labs but then warm student tubes to room temperature in a warm, not
hot, water bath.
Starch suspension (LM page 231). Prepare 20 mL per student group. A fresh supply of
this solution must be carefully prepared every day. To make a 1% starch suspension,
dissolve 1 g of starch in a small amount of cold water to form a paste. Add this to 100 mL
of boiling distilled water, and mix a few minutes. Cool. Add a pinch of sodium chloride
(NaCl).
Iodine (IKI) solution (LM page 231). Prepare one dropper bottle per student group. For
ease of comparison, the same amount should be used each time. Pre-made iodinepotassium-iodide solution can be purchased, or the ingredients can be purchased
separately as potassium iodide (KI) (Carolina 88-3790, -3792) and iodine (I) (Carolina
86-8970, -8972). These dry ingredients have a long shelf life and can be mixed as needed,
according to the instructions in Laboratory 2.
EXERCISE QUESTIONS
18.1 Protein Digestion by Pepsin (LM pages 227–28)
The stomach has a very low pH. Does this indicate that pepsin works effectively in
an acidic or basic environment? acidic Therefore you would hypothesize that the
yield from this enzymatic reaction will be higher if the pH is optimum and the
temperature is warm.
Experimental Procedure: Protein Digestion (LM pages 227–28)
Table 18.1 Protein Digestion by Pepsin
Tube Contents
Temperature* Results
of Test
1
Albumin
37°C
Pinkish-purple
Pepsin
HCl
Biuret reagent
Explanation
Digestion; enzyme and
correct pH
38
2
Albumin
22°C
Light purple
Some digestion; temperature
Pepsin
to pale
is low
HCl
pinkish purple
Biuret reagent
3
Albumin
37°C
Purple
No digestion; incorrect pH
Pepsin
Water
Biuret reagent
4
Albumin
37°C
Purple
No digestion (no enzyme);
Water
Biuret reagent
control
* If solutions are cold, warm the tubes to room temperature in a warn, not hot, water bath
before incubating and this will shorten the time of incubation.
Conclusions: Protein Digestion (LM page 228)
•
Explain your results in Table 21.1 by giving an explanation why digestion did
or did not occur. Now show here that Tube 1 met all the requirements for digestion.
Pepsin is the correct enzyme.
Albumin is the correct substrate.
37º C is the optimum temperature.
HCl provides the optimum pH
1 ½ hours provides time for the reaction to occur.
•
Which tube was the negative control? tube 4 Explain. Tube 4 contained no
enzyme (pepsin).
•
If this control tube had given a positive result for protein digestion, what
could you conclude about this experiment? The experiment is invalid.
18.2 Fat Digestion by Pancreatic Lipase (LM pages 229–30)
With regard to the second step, would the pH of the solution be lower before or
after the reaction? The pH would be lower after the reaction.
Test for Fat Digestion (LM pages 230)
Experimental Procedure: Fat Digestion
2. What role does phenol red play? It is a pH indicator.
3. What role does lipase play? It is the enzyme.
Table 18.2 Fat Digestion by Pancreatic Lipase
Tube Contents
Color Change
Initial Final
1
Vegetable oil
Red Yellow
Phenol red
Pancreatin
Bile salts
2
Vegetable oil
Red Pink (red
Phenol red
at border)
Pancreatin
Time Taken
Explanation
60-90 minutes
Digestion
same
Limited digestion; no
emulsifier
39
3
Vegetable oil
Phenol red
Water
Red
Red
same
No digestion (no
enzyme or emulisifer);
control
*If solutions are cold, warm to room temperature in a warm, not hot, water bath before
incubating; this will shorten the time needed for incubation.
Conclusions: Fat Digestion (LM page 230)
•
Explain your results in Table 18.2 by giving a reason why digestion did or
did not occur.
•
What role did bile salts play in this experiment? Bile salts act as an emulsifier
and break large drops of fat into very small droplets. This makes more fat molecules
available for digestion.
•
What role did phenol red play in this experiment? Phenol red was a pH
indicator that turns yellow when digestion occurs.
•
Which test tube in this experiment could be considered a negative control?
tube 3
18.3 Starch Digestion by Pancreatic Amylase (LM pages 231- 32)
1. If digestion does not occur, which will be present—starch or maltose? starch
2. If digestion does occur, which will be present—starch or maltose? maltose
Experimental Procedure: Starch Digestion (LM pages 231–32)
5. Examine all your tubes in the test tube rack and decide whether digestion occurred (+)
or did not occur (--). Complete Table 18.3.
Table 18.3 Starch Digestion by Amylase*
Tube Contents
Time Type
of Test
Test Results
(+ or —)
Digestion
(+ or —)
1
2
3
4
5
6
Pancreatic-amylase
Starch
Pancreatic -amylase
Starch
Pancreatic -amylase
Starch
Pancreatic -amylase
Starch
Water
Starch
Water
Starch
0
Iodine
+
—
0
Benedict’s
—
—
T
Iodine
—
+
T
Benedict’s
+
+
T
Iodine
+
—
T
Benedict’s
—
—
*If solutions are cold, warm to room temperature in a warm, not hot, water bath, waiting
the 30 minutes and/or testing directly.
40
Conclusions: Starch Digestion (LM page 232)
•
Considering tubes 1 and 2, this experimental procedure showed that time
must pass for digestion to occur.
•
Considering tubes 5 and 6, this experimental procedure showed that an
active enzyme must be present for digestion to occur.
•
Why would you not recommend doing the test for starch and the test for
sugar on the same tube? The results may not be clear cut for the second test.
•
Which test tubes served as a negative control for this experiment? 5 and 6
Explain your answer. Does not contain the enzyme, the substance being tested.
18.4 Requirements for Digestion (LM page 233)
Explain in Table 18.4 how each of the requirements listed influences effective
digestion.
Table1 18.4 Requirements for Digestion
Requirement
Explanation
Specific enzyme
Each enzyme speeds only one type of reaction.
Specific substrate Each enzyme combines only with its substrate.
Warm temperature Chemical reactions occur at a faster rate at warm temperatures
than at cold temperatures.
Specific pH
Optimum pH maintains the shape of the enzyme so that the enzyme
will combine with its substrate.
Time
It takes time for the reaction to occur
Fat emulsifier
Fats are insoluble in water. The emulsifier breaks up fat so that fat
droplets are exposed to the enzyme.
1. How is the amount of substrate reduced? Patient can eat very little at a time.
2. How is the amount of digestive enzymes reduced? Duodenum is shortened just
where pancreatic enzymes enter the duodenum. A smaller tract produces less enzymes,
such as peptidases, also.
3. How is the time reduced? Food passes more quickly through a short digestive tract.
4. What makes the pH of the small intestine higher than before? Pancreatic juices,
which are basic, no longer enter the tract as before.
5. How is fat emulsification reduced? Bile salts do not enter the duodenum as before.
6. How does surgery to reduce obesity sometimes result in malnutrition. The
requirements for digestion as outlined in Table 21.4 are not met.
LABORATORY REVIEW 18 (LM page 234)
1.
Where in the body does starch digestion occur? mouth and small intestine
Protein digestion occur? stomach and small intestine Fat digestion occur? small
intestine
2.
Why would you not expect amylase to digest protein? Enzymes are specific. An
enzyme that breaks down starch (i.e., amylase) cannot break down protein.
41
3.
Relate the expectation of more product per length of time to the fact that
enzymes are used over and over. With time, each enzyme molecule can act more times;
hence, more product.
4.
Why do enzymes work better at their optimum pH? Optimum pH maintains
the shape of the enzymes.
5.
Why is an emulsifier needed for the lipase experiment but not for the pepsin
and amylase experiments? Fat is insoluble in water, and the emulsifier makes it
disperse in water.
6.
Which of the following two combinations is most likely to result in digestion?
a. Pepsin, protein, water, body temperature
b. Pepsin, protein, hydrochloric acid (HCl), body temperature.
Explain your answer. The second combination (pepsin, protein, hydrochloric
acid [HCl], body temperature) is more likely to result in digestion because all
requirements for digestion are present, including optimum pH for pepsin.
7.
Which of the following two combinations is most likely to result in digestion?
a. Amylase, starch, water, body temperature, testing immediately
b. Amylase, starch, water, body temperature, waiting 30 minutes
Explain your answer. The second combination (amylase, starch, water, body
temperature, waiting 30 minutes) is more likely to result in digestion because time has
been given for enzyme to act.
8.
Relate the composition of fat to the test used for fat digestion. A fat consists of
glycerol and fatty acids. Fatty acids released with digestion bring about acidic conditions,
as detected by a pH indicator.
9.
Given that, in this laboratory, you tested for the action of digestive enzymes on
their substrates, what substance would be missing from a negative control
sample? The enzyme is missing from a negative control sample.
10. What substance would be present in a positive control sample? The substance
being tested.
42
Laboratory
19
Energy Requirements and Ideal Weight
(LM pages 235–250)
Fourth Edition
This is a new laboratory.
MATERIALS AND PREPARATIONS
Instructions are grouped by exercise. Some materials may be used in more than one
exercise.
Hardware
_____
_____
_____
_____
_____
scale and height measuring device
three-day activity and three-day food diary (one per person)
calculator
tape measure
calipers
Calorie-counting guides may be helpful in completing the Food Diary.
EXERCISE QUESTIONS
All answers depend on the particular individual.
LABORATORY REVIEW 19 (LM page 116)
1.
What do you call a listing of all foods eaten for a day? daily food diary
2.
What does kcal mean? kilocalories
3.
Daily energy requirement includes energy for physical activity, SDA, and
what else? BMR
4.
Give an example of a basal metabolism activity. heartbeat, breathing, nerve
impulses
5.
SDA refers to energy needed for what activity? processing food
43
6.
With age, the BMR decreases. What is the implication for daily energy
intake? decrease food intake
7.
Why does a tall, thin person have a higher BMR than a short, stout person?
BMR is dependent on body surface area
8.
Daily energy requirement must be in balance with what to not gain weight?
daily energy intake
9.
If the average intake/day equals the average energy requirement/day, the
person will not gain or lose weight.
10.
Ideal weight includes lean body weight and what else? weight of body fat
11.
Generally speaking, a male should have no more than what percentage body
fat? 16%
12.
Calculation of ideal weight is considered to be the most accurate if it is based
on your body composition.
13.
How many kcal are equal to a pound of fat? 3,500
14.
In which sex is it natural to have a higher percentage of body fat? females
15.
Why do males typically have a higher basal metabolic rate than females?
Males have a greater muscle mass and a lower body fat percentage. This means they
have a higher basal metabolic rate.
16.
Why is energy needed when the body is at rest? The beating of the heart,
breathing, maintaining body temperature, and sending nerve impulses are some of the
activities that require energy to maintain life.
17.
Why is energy needed to process food? Muscles that move food along the
digestive tract and glands that make digestive juices require energy.
18.
Why should someone monitor his or her average daily energy intake when
attempting to maintain average body weight? If this amount increases and is not
compensated for by physical activity, the person will gain weight.
.
44
Laboratory
20
Basic Mammalian Anatomy II
(LM pages 251–266)
Fourth Edition
This lab has been reorganized and now begins with the anatomy of the heart, before
going on to a review of the respiratory and digestive systems before the reproductive
systems are dissected. The dissection of the reproductive systems is optional.
MATERIALS AND PREPARATIONS
Instructions are grouped by exercise. Some materials may be used in more than one
exercise.
Special Requirements
Preserved Specimens. It is assumed that the fetal pigs required for this lab have
previously been used in Laboratory 20, Basic Mammalian Anatomy I.
20.1 The Cardiovascular System (LM pages 252-56)
_____ model, human heart
Heart model Heart models are available from a number of supply houses. The Carolina
Biological Supply Company has a variety of heart models that vary widely in price.
See Carolina’s “Models” section
20.2 Respiratory, Digestive, and Urinary Systems (LM pages 257–59)
_____
container, small, of water
_____
meter stick or measuring tape
20.3–20.4 Male and Female Reproductive Systems (LM pages 260-65)
Fetal pig dissection (optional) All exercises in these sections expose students to
preservative chemicals. Safety goggles, latex and nonlatex gloves, and lab coats or other
clothing protection are recommended.
EXERCISE QUESTIONS
20.1 The Cardiovascular System (LM pages 252-59)
Anatomy of the Heart
Observation: Heart (pages 252-54)
2. Which ventricle is more muscular? Left ventricle Why is this appropriate? The left
ventricle pumps blood to the systemic circuit.
45
3d. Why are the pulmonary veins colored red in Figure 20.1 and 20.2? Because they
carry O2 rich blood.
Tracing the Path of Blood Through the Heart (LM page 254)
To demonstrate that O2-poor blood is kept separate from O2-rich blood, trace the
path of blood from the right side of the heart to the aorta by filling in the blanks
with the names of blood vessels and valves.
From Venae Cavae
Right atrium
AV valve
Right ventricle
Semilunar valve
Pulmonary artery
To Lungs
From Lungs
Pulmonary veins
Left atrium
AV valve
Left ventricle
Semilunar valve
To Aorta
Pulmonary Circuit (LM page 254)
1. Sequence the blood vessels in the pulmonary circuit to trace the path blood from
the right ventricle to the left atrium of the heart:
Right ventricle of the heart
pulmonary trunk
pulmonary artery
Lungs
pulmonary veins
Left atrium of the heart
2.
Which of these blood vessels contains O2-rich blood? pulmonary veins
Systemic Circuit (LM page 254–55)
1. With the help of Figure 20.3, complete Table 20.1.
Table 20.1 Other Blood Vessels in the Systemic Circuit
Body Part
Artery
Vein
Head
Carotid
Jugular
Front legs in pig
Kidney
Hind legs
Subclavian
Renal
Iliac
Subclavian
Renal
Iliac
46
2.
With the help of Figure 20.3 and Table 20.1, sequence the blood vessels in the
systemic circuit from the heart to the kidneys and from the kidneys to the heart.
Left ventricle of heart
aorta
renal artery
Kidneys
renal vein
posterior vena cava
Right atrium of heart
Vertebrate Cardiovascular Systems (LM page 256)
Compare the cardiovascular systems of the vertebrates in Figure 20.4 and answer
the following questions.
1. Do fish have a blood vessel that returns blood from the gills to the heart? no
Would you expect blood pressure to be high or low after blood has moved through
the gills? low
2. What animals studied have pulmonary vessels that take blood from the heart to
the respiratory organ and back to the heart? amphibians, reptiles, and mammals
What is the advantage of a pulmonary circuit? Returns blood to heart where it is
pumped to rest of body
3. Which of these animals has a four-chambered heart? Reptiles (crocodilians and
birds) and mammals. What is the advantage of having separate ventricles? Keeps
O2-rich blood separate from O2-poor blood
4. The circulatory system distributes the heat of muscle contraction in birds and
mammals. Is the anatomy of birds and mammals conducive to maintaining a
warm internal temperature? yes Explain your answer. Only by distributing heat
can these animals have a warm internal temperature.
20.2 Respiratory, Digestive, and Urinary Systems (LM pages 257-59)
Observation: Organs of the Respiratory System and Digestive Systems
Digestive System (page 257)
2. Open one side of the stomach. Does it appear smooth or rough? Rough
7. Measure and record in meters the length of the intestinal tract. about 8 meters
8. Why would such a great length be beneficial to the body? ________
Urinary System (LM pages 259)
Observation: Urinary System in Pigs
5. Sequence the organs in the urinary system to trace the path of urine from its
production to its exit. Urine travels from a kidney to a ureter, to the urinary bladder,
to the urethra.
20.3 Male Reproductive System (LM pages 260-62)
Observation: Male Reproductive System in Pigs (LM pages 260-62)
Penis, Urethra, and Accessory Glands
6. Sequence the organs in the male reproductive system to trace the path of sperm
from the organ of production to the penis. Sperm travel from the testis to the
epididymis, to the vas deferens, to the urethra within the penis.
47
Comparison of Male Fetal Pig and Human Male (LM page 262)
Complete Table 20.3, which compares the location of the penis in these two
mammals.
Table 20.3 Location of Penis in Male Fetal Pig and Human Male
Fetal Pig
Human
Penis
Underneath the ventral skin surface,
Hangs in front
posterior to the umbilical cord
of scrotum
20.4 Female Reproductive System (LM pages 263-65)
Observation: Female Reproductive System in Pigs (LM pages 263)
4. The vagina plays a critical role in reproduction even though development of the
offspring occurs in the uterus. Explain. The vagina allow the sperm to enter the
female’s reproductive system where the egg awaits fertilization.
Comparison of Female Fetal Pig to Human Female (LM page 265)
Complete Table 20.5, which compares the appearance of the oviducts and the
uterus, as well as the presence or absence of a urogenital sinus in these two
mammals.
Table 20.5 Comparison of Female Fetal Pig with Human Female
Fetal Pig
Human
Oviducts
Each leads to a
Each leads to upper
uterine horn.
portion of uterus.
Uterus
Two horns plus
No uterine horns
body of uterus
Urogenital sinus
Vagina and urethra
Vagina opens separately
enter urogenital sinus
LABORATORY REVIEW 20 (LM page 266)
1.
What are the four chambers of the mammalian heart? The four chambers are
the right and left atria, and the right and left ventricles.
2.
Contrast the pumping function of the right and left sides of the heart. The
right side of the heart pumps blood to the lungs; the left side pumps blood to the body.
3.
Sequence the blood vessels in the systemic system, to trace the path of blood
from the left ventricle to the kidneys and back to the right atrium. left ventricle,
aorta, renal artery, capillaries in kidney, renal vein, posterior vena cava, right atrium
4.
Sequence the organs of the respiratory system from the glottis to the lungs.
glottis, trachea, bronchi, lungs
5.
What's the difference between the ureters and the urethra in the urinary
system? Both are tubular but the ureters carry urine from the kidneys to the urinary
bladder. The urethra carries urine from the urinary bladder to the urogenital opening.
48
6.
Sequence the following organs: stomach, large intestine, small intestine,
pharynx, mouth, esophagus, anus. A logical order would be: mouth, pharynx,
esophagus, stomach, small intestine, large intestine, anus.
7.
Sequence the path of sperm from the testes to the urogenital opening. Testis
epididymis, vas deferens, urethra, urogenital opening
8.
What organs enter the urogenital sinus in female pigs? Urethra, vagina, and
rectum enter the urogenital sinus in female pigs.
9.
Which organ in males produces sperm, and which organ in females produces
eggs? In the male, the testes produce sperm; in the female, the ovaries produce eggs
10.
How and when do sperm acquire access to an egg in mammals? During
copulation (in animals)or intercourse (in humans), the male ejaculates sperm into the
vagina of a female.
49
Laboratory
21
Nervous System and Senses
(LM pages 267–85)
Fourth Edition
The nervous system portion of this lab was reorganized into two portions: 21.1 Central
Nervous System and 21.2 Peripheral Nervous System. Sheep brain dissection begins as
before with the ventricles but then proceeds from the cerebrum to the medulla oblongata.
MATERIALS AND PREPARATIONS
Instructions are grouped by exercise. Some materials may be used in more than one
exercise.
Special Requirements
Preserved specimens. (LM page 268). Preserved sheep brains are required for this lab.
Fresh materials (LM page 284). LifeSavers candy
21.1 The Central Nervous System (LM pages 268-72)
_____ sheep brain, preserved
_____ safety goggles
_____ latex gloves and/or non-latex gloves
_____ lab coats or other clothing protection
_____ human brain, model
_____ slide, prepared: spinal cord, cross section
_____ microscopes, compound light
_____ lens paper
21.2 Peripheral Nervous System (LM pages 272–74)
_____ meter stick
21.3 Animal Eyes (LM pages 274-79)
_____ model, human eye
_____ pencil with eraser
_____ meter stick
21.4 Animal Ears (LM pages 280–82)
_____ model, human ear
_____ tuning fork or two spoons
21.5 Sensory Receptors in Human Skin (LM page 282-83)
_____ model, human skin
_____ scissors, fine point; or hairpin
50
_____
_____
_____
_____
beakers, 1,000 ml, three
ice
water: ice-cold, room-temperature, warm
thermometer, centigrade
21.6 Human Chemoreceptors (LM pages 284)
_____ rubber or latex examining gloves
_____ LifeSavers candy, various flavors
EXERCISE QUESTIONS
21.1 The Central Nervous System (LM pages 268-72)
The Human Brain (LM pages 270-271)
Based on your knowledge of the sheep brain, complete Table 21.1 by stating the
major functions of each part of the brain listed. Also label Figure 21.3b.
Table 21.1 Summary of Brain Functions
Part
Major Functions
Cerebrum
Communicates with and coordinates activities of other parts
Cerebellum
Helps produce smooth, voluntary, coordinated movements
Diencephalon
Thalamus
Receives sensory input except smell and passes much of it on to the
cerebrum
Hypothalamus
Helps maintain homeostasis
Brain stem
Midbrain
Relay station that has centers for visual, auditory, and tactile
responses
Pons
Relay station between cerebellum and rest of CNS; helps medulla
oblongata regulate breathing rate and certain reflexes
Medulla oblongata Contains reflex centers for regulating heartbeat, breathing, and
vasoconstriction. Also has reflex centers for head
movements in response to visual and auditory stimuli.
Which parts of the brain would work together to achieve:
1.
Good eye-hand coordination cerebrum and cerebellum
2.
Concentrating on homework when TV is playing thalamus and cerebrum
3.
Avoiding dark alleys while walking home at night cerebrum and midbrain
4.
Keeping the blood pressure constant Hypothalamus and medulla oblongata
Comparison of Vertebrate Brains (LM page 271-22)
Figure 21.3b: On the left: Diencephalon(hypothalamus and thalamus), cerebrum,
cerebellum. On the right: Brain stem (midbrain, pons, medulla oblongata)
2. Record your observations in Table 21.2
51
Table 21.2
The observations should include the recognition that the cerebrum in particular, and also
the cerebellum, become more prominent from fish to mammal.
21.2 The Peripheral Nervous System (LM page 272–73)
Spinal Nerves (LM page 273)
Describe the pathway of information, starting with the pain receptor in your foot,
that would allow you to both feel and respond to this unwelcome stimulus. As
illustrated in Figure 21.5, sensory receptor in skin generates nerve impulses that move
along sensory axon toward the spinal cord. Sensory neurons that enter the cord dorsally
pass signals on to many interneurons. Some of these interneurons travel to brain and
some synapse with motor neurons. Nerve impulses travel along motor axons to muscle
fibers, which bring about a response to the stimulus.
Spinal Reflex (LM page 274)
Experimental Procedure: Spinal Reflex
Knee-Jerk (Patellar) Reflex
3.
In this relaxed state, does the leg flex (move toward the buttocks) or extend
(move away from the buttocks)? The leg extends.
21.3 Animal Eyes (LM pages 274-79)
Observation: Invertebrate Eyes (LM page 276)
3.
Explain why the eye of a fly can detect motion better than the eye of a
chambered nautilus.
Observation: The Human Eye (LM page 276-78)
2.
Trace the path of light from outside the eye to the retina. Light rays pass
through the cornea, through the aqueous humor and pupil, to the lens, to the vitreous
humor, to the photoreceptors in the retina.
3.
Which structure holds the lens and is involved in accommodation? ciliary
body
4.
Which of the structures listed in Table 21.3 aid in refracting and focusing
light rays? cornea, lens, humors
5.
Specifically, what are the sensory receptors for sight, and where are they
located in the eye? The receptors are the rod cells and cone cells, which are located in
the retina.
6.
What structure takes nerve impulses to the brain from the rod cells and cone
cells? optic nerve
7.
Which cerebral lobe processes nerve impulses from the eye? occipital lobe
The Blind Spot of the Eye (LM pages 278)
Experimental Procedure: Blind Spot of the Eye (LM page 278)
Left Eye/Right Eye
6.
With your partner’s help, measure the distance from your eye to the paper
when the circle (for left eye) and cross (for right eye) first disappeared. Distances
will vary with the individual. Generally, the blind spot is within 30 cm (1 foot) of the eye.
52
Experimental Procedure: Accommodation of the Eye (LM page 279)
5–7. Measure the distance (in centimeters) between the pencil and your eye.
Distances will vary with the individual.
8.
How “old” is the eye you tested? Answers will vary with the individual.
21.4 Animal Ears (LM pages 280–83)
Physiology of the Human Ear (LM page 282)
Experimental Procedure: Locating Sound (LM page 282)
2 a-e. Record the subject’s perceptions. Perceptions will vary with the individual.
3.
Is there an apparent difference in hearing between the subject's two ears?
Answers will vary with the individual.
21.5 Sensory Receptors in Human Skin (LM page 282-83)
Sense of Touch (LM page 283)
3a–d. Record the shortest distance between the hairpin or scissor points for a twopoint discrimination. Distances will vary with the individual.
4.
Which of these areas apparently contains the greatest density of touch
receptors? the fingers Why is this useful? This sensitivity enables humans to manipulate
sophisticated tools.
5.
Do you have a sense of touch at every point in your skin? Student answers will
vary. Explain. Touch receptors are plentiful in the skin.
6.
What specific part of the brain processes nerve impulses from touch and pain
receptors? primary somatosensory area in the parietal lobe
Sense of Heat and Cold (LM page 283)
4.
Record the sensation in the right and left hands.
a.
Right hand feels cold
b.
Left hand
feels warm
5.
Explain your results. Each hand has accommodated to the temperature of the
original beaker.
21.6 Human Chemoreceptors (LM page 284)
The taste receptors, called taste buds, and the smell receptors, called olfactory cells,
located in the nasal cavities are the chemoreceptors that respond to molecules in the
air and water. Nerve impulses from taste receptors go to the parietal lobe while
those from the smell receptors go to the frontal lobe of the brain.
Experimental Procedure; Sense of Taste and Smell (LM page 284)
6. The experimenter records the guess and the actual flavor in Table 21.6
Table 21.6 Taste and Smell Experiment
Table results will depend on the individual being tested.
Conclusions: Sense of Taste and Smell (LM page 284)
 From your results, how would you say that smell affects the taste of
LifeSavers candy? Most students report a sweet or sour taste before they unplug
their nose, then afterwards they report the actual fruit flavor.
53
 What do you conclude about the effect of smell on your sense of taste? The
sense of smell enhances or complements taste.
LABORATORY REVIEW 21 (LM pages 285)
1.
Describe the cerebrum of the human brain, and state a function. The
cerebrum of the human brain is the most superior and highly convoluted region that
covers much of the rest of the brain. It functions in critical thinking and memory. The
cerebrum controls the rest of the brain.
2.
The brain stem includes the medulla oblongata, the pons, and the midbrain.
Explain the expression brain stem as an anatomical term. The brain stem is the most
inferior portion of the brain and is attached to and somewhat resembles the spinal cord.
3.
Describe the location of the gray/white matter of the spinal cord, and give a
function for each. Gray matter has a butterfly shape and is located in the center of the
cord. It contains interneurons, which take messages from sensory neurons to motor
neurons. White matter lies outside gray matter and contains long fibers, which take
messages up and down the cord.
4.
State, in order from receptor to effector, the neurons associated with a spinal
reflex. The neurons associated with a spinal reflex are, in order: sensory neuron,
interneuron, and motor neuron.
5.
Trace the path of light in the human eye—from the exterior to the retina and
then from retinal nerve impulses to the brain. The path of light is: cornea through the
pupil to aqueous humor, to lens, to vitreous humor, to photoreceptors in the retina. Nerve
impulses travel from the retina in the optic nerve to the brain.
6.
Contrast the eye of an arthropod with the eye of a squid and human. An
arthropod has a compound eye (many individual units of sight). In squids and humans,
light is focused on a single layer of the eye that contains photoreceptors.
7.
If you move an illustration that contains a dark circle and a dark cross
toward an eye, one or the other may disappear. Give an explanation for this. The eye
has a blind spot where the optic nerve enters the eye, and since there are no
photoreceptors here, no sight is possible.
8.
Trace the path of sound waves in the human ear—from the tympanic
membrane to the receptors for hearing. The path of sound waves is: tympanic
membrane to maleus, to incus, to stapes, to fluid within cochlea. Pressure waves in the
fluid stimulate hair cells (receptors for hearing) in spiral organ.
9.
Compare the manner in which a grasshopper “hears” to the way a human
hears. In the grasshopper, vibration of the tympanum results in nervous stimulation. In
humans, the receptors for hearing are far removed from the tympanic membrane.
54
10.
Name four structures located in the dermis of the skin. Structures located in
the dermis include: hair follicles, sensory receptors, sweat glands, and oil glands.
55
Laboratory
22
Effects of Pollution on Ecosystems
(LM pages 287–95)
Third Edition
This lab was revised to better present ecological principles and how pollution affects
ecosystems.
MATERIALS AND PREPARATIONS
Instructions are grouped by exercise. Some materials may be used in more than one
exercise.
Special Requirements
Living material. Hay infusion cultures must be started 2 to 2½ weeks before use, and
seed germination must be started at least 4 days prior to the lab (22.1 Studying the Effects
of Pollutants); Gammarus (p. 291) Chlorella (common pond algae), and Daphnia (22.2
Studying the Effects of Cultural Eutrophication).
Equipment (LM page 293). Spectrophotometers
All Exercises
_____
_____
_____
_____
_____
_____
_____
_____
_____
_____
22.1
safety goggles
latex gloves and/or nonlatex gloves
lab coats or other clothing protection
1% sulfuric acid (H2SO4)
pH meter or litmus paper
droppers
slides and coverslips
lens paper
microscopes, compound light
microscopes, stereomicroscope
Studying the Effects of Pollutants (LM pages 288-91)
Experimental Procedure: Study of Hay Infusion Cultures (LM pages 288-291)
_____ hay or grass clippings or hay infusion kit
_____ peptone solution or Timothy Hay Culture Media
_____ large beaker, or wide-mouth glass jar, with screw-top lid
_____ depression slides (optional), use concavity slides
_____ 1% sulfuric acid (H2SO4)
56
Hay infusion cultures Add tap water and a pinch of peptone (a nutrient) (or Timothy’s Hay
Culture Media) to hay (or grass clippings) in an open beaker. Do not aerate. In about 24
hours or less, a variety of bacteria, including motile bacteria, will develop. In a few days,
protists will develop, and can be seen feeding on the bacteria. Alternately, add a small
amount of pond water including some mud from the bottom of the pond. The motility of
microorganisms can be observed using a depression slide.
You many also purchase an infusion culture. The infusion can be used to mass
culture many species of protozoans and other invertebrates. Carolina’s infusion culture
set includes timothy hay, a plastic culture aquarium, spring water, and instructions. Use a
1-gallon, wide-mouth jar covered loosely with screw-cap, and maintain the culture in a
well-lighted place, but not in direct sunlight.
To prepare the various types of cultures needed, follow these directions:
Control culture: Prepare the culture according to the instructions provided. Do not
cover.
Enriched culture: Add additional peptone to the culture.
Oxygen-deprived culture: Prepare the same as the control culture, but use minimal
oxygen—use saran wrap to tightly cover the culture, if in a beaker. Use a screw-top lid if
the culture is in a wide-mouth glass jar. Do not aerate.
Acidic culture: Adjust a portion of the control culture to pH 4 using 1% sulfuric acid.
1% sulfuric acid solution (LM page 289). Add 1 ml of sulfuric acid to 100 ml of water
to adjust to pH 4.
Experimental Procedure: Effect of Acid Rain on Seed Germination (LM page 290)
_____ petri dishes with lids
_____ labels
_____ bean seeds
_____ filter paper for germinating seeds
_____ sterile spring water
_____ spring water, adjusted to pH 4
Seed germination (LM page 290). Line two petri dishes with two layers of filter-paper
disks. In dish #1 (the control), dampen the paper with spring water. In dish #2 (the acidic
solution), dampen the paper with an acidic solution (control solution adjusted to pH 4
using 1% sulfuric acid), which simulates acid rain. Arrange four to six bean seeds in each
petri dish, and cover with two filter-paper disks. Replace the lids on the petri dishes, and
label the dishes appropriately. The seeds should germinate in at least four days.
Experimental Procedure: Gammarus (LM page 291)
_____ sterile spring water
_____ containers for spring water
_____ amphipod, Gammarus culture
_____ beakers, 50 and 200 ml
_____ boiling water bath
_____ hot plate
_____ beaker (size varies)
57
_____ beaker clamps
_____ thermometer, Celsius. See Carolina’s Laboratory Equipment and
Supplies section.
_____ boiling chips, pumice
_____ water, boiled and cooled to 26.°C
_____ aquarium net, 4” x 2.5”
_____ spring water, adjusted to pH 4 with vinegar
Gammarus (LM page 291). Large quantities of spring water (50 ml per group) will be
needed for the Gammarus culture. Expect some Gammarus in each laboratory to die.
Therefore, purchase half again as many as you determine you will need. Other species
may also be used.
22.2 Studying the Effects of Cultural Eutrophication (LM pages 292–94)
Observation: Daphnia Feeding
_____ petroleum jelly
_____ petri dishes, small
_____ Daphnia culture
_____ indigo carmine
_____ water, distilled
_____ probe or dissecting needle (to turn Daphnia over)
Observation: Daphnia Feeding on Chlorella (LM page 293)
_____ spectrophotometers, spectronic educator
_____ beakers
_____ kimwipes, cleaning tissue
_____ wash bottle of ethanol
_____ wash bottles of distilled water
_____ two cuvettes for spectrophotometer
_____ Pasteur pipet
_____ Chlorella (common pond algae) culture (10 cc)
_____ Daphnia culture
_____ test tube racks
Spectrophotometer and tubes (cuvettes) (LM page 293). The most common
instrument for teaching use is the Bausch and Lomb Spectronic 20. For this laboratory,
the wave-length indicator should be set at 635 nm (or 0.635 mm). The instrument must be
calibrated for zero and infinite absorbance. Calibrate for infinite absorbance by using the
left-hand knob to line up the needle with the left-most marker (an infinity symbol). Then
insert a clean cuvette of distilled water and adjust for 100% transmittance using the righthand knob. The Chlorella culture should be just visibly green.
The Daphnia should be starved in clean, aged water (stale tap water that has been
allowed to stand for a few days to allow chlorine to escape) for an hour or so prior to the
lab. This clears their gut, since feces production would foul the experimental vessel and
reduce the apparent feeding rate.
58
Preparing cuvettes (LM page 293). Next to each spectrophotometer, place a kimwipelined beaker containing two optically matched cuvettes, a Pasteur pipette, a wash bottle
of distilled water, and a wash bottle of ethanol. Have students clean cuvettes with the
ethanol thoroughly after use, and place cuvettes upside down in the beaker to drain.
0.1% carmine solution (LM page 293). Dissolve 0.1 g of indigo carmine in 100 ml of
distilled water.
EXERCISE QUESTIONS
22.1 Studying the Effects of Pollutants (LM pages 288-92)
Experimental Procedure: Effect of Pollutants on a Hay Infusion Culture (LM page 28889)
1-4 Record your estimation [of species composition and species diversity] in the
second and third column of Table 22.1.
Table 22.1 Effect of Pollution on Hay Infusion Culture
Type of Culture
Species Composition Species Diversity
Control
High
High
Oxygen-deprived
Medium to Low
Medium to Low
Acidic
Medium to Low
Medium to Low
Enriched
Medium to Low
Medium to Low
Explanation
Normal conditions
Low cell respiration
Enzymes altered
Low oxygen
Conclusions: Effect of Pollution on Hay Infusion Culture (LM page . 289)
See last column of Table 22.1
Experimental Procedure: Effect of Acid Rain on Seed Germination (LM pages 290)
In other words, it is hypothesized as acidity increases, the more likely seeds will not
germinate.
1. Record the pH of each solution in Table 22.2
2. Count the number of germinated sunflower seeds in each container, and complete
Table 22.2.
Table 22.2 Effect of Increasing Acidity on Germination of Sunflower Seeds.
Concentration
pH
Number of Seeds
Percent Germination
of Vinegar
that Germinated
0% - 100%
Decreasing
Decreasing seed and percent
pH
germination
Conclusions: Effect of Increasing Acidity on Germination of Sunflower Seeds (LM page
290).
 Explain why acid rain is expected to inhibit metabolism, and therefore,
seedling development. A low pH changes the shape of enzymes and decreases
their activity
 Do the data support your hypothesis. Most likely, yes.
59
Study of Gammarus (LM pages 291)
 Record the pH of the water. Close to neutral pH.
 Do they all use their legs in swimming? No, they move by flexing the
appendages on the side of their body, one side at a time.
 What do Gammarus do when they “bump” into each other? They pass each
other quickly, going off in a new direction.
Control Sample (LM page 291)
During a 5-minute time span record the amount of time spent doing each of these
behaviors.
Students results will vary according to the Gammarus they are observing.
Test Sample (LM page 291)
During a 5-minute time span record the amount of time spent doing each of these
behaviors.
Students results will vary according to the Gammarus they are observing.
Conclusions (LM page 291-292)
 Draw a conclusion from the study: Conclusions will vary
 Create a food chain: algae — protozoans —Gammarus —fish —humans.
a. What would happen to this food chain if the water was
oxygen deprived? Populations would be smaller and it's possible it would die out
before humans benefit from it.
Acidic? Populations would be smaller and it's possible it would die out before
humans benefit.
Enriched with inoranic nutrients.(short term and long term) short term:
Populations are expected to increase in size. long term: When algae die off
bacteria of decomposition uses up all the oxygen and the fish populations die, to
the detriment of humans.
Conclusion: Studying the Effects of Pollutants (LM page 292)
•
Give an example to show that the hay infusion study pertains to real
ecosystems? Ecosystems are sensitive to temperature and pH variations.
•
What are the potential consequences of acid rain on crops that reproduce by
seeds? Yield will be less than expected On the food chains of the ocean? Animals will
have less to eat.
•
How does the addition of nutrients affect species composition and species
diversity of an ecosystem over time? Initially, the addition of nutrients causes increase
in producers and consumers. but over time, it causes a decrease when the algae die off.
22.2 Studying the Effects of Cultural Eutrophication (LM page 292-294)
Observation: Daphnia Feeding
5.
Does the carmine travel completely through the gut in 30 minutes? yes
Experimental Procedure: Daphnia Feeding on Chlorella (LM page 293)
4.
Record your reading here. Readings may vary.
7.
Record your reading here and explain why the absorbance changed. Daphnia
was allowed to feed on Chlorella.
Experimental Procedure: Case Study in Cultural Eutrophication (LM page 293-294)
60
1. Using this information, complete Table 22.3.
Table 22.3 Daphnia Filtering
Number of Daphnia/Liter
Percent of Lake Filtered
10
24%
50
120%
2. Using this information, complete Table 22.4.
Table 22.4 Cultural Eutrophication
Number of Condominiums Phosphorus Added
10
1 kg
20
2 kg
30
3 kg
40
4 kg
50
5 kg
Increase in Algal Population
30%
60%
90%
120%
150%
Conclusion: Studying the Effects of Cultural Eutrophication (LM page 294)
•
How many condominiums would you allow the developer to build? no more
than forty
•
What other possible impact could condominium construction have on the
condition of the lake? cultural eutrophication due to fertilizer runoff
LABORATORY REVIEW 22 (LM page 295)
1.
What type of population would you expect to be the largest in most
ecosystems? Algae or plants Explain. They produce the food for the other organisms in
an ecosystem.
2.
What causes acid rain? When fossil fuels are burned, acids enter the atmosphere
and then fall to the Earth’s surface in rain or snow.
3.
Why is acid deposition harmful to organisms? It causes organisms to take in,
for example, water that has a low pH. A low body pH is harmful to enzymes.
4.
Name the type of pollution that results when water from rivers and ponds is
used for cooling power plants, and explain why it has detrimental effects. Thermal
pollution removes oxygen from the water because warm water does not hold as much
oxygen as cold water.
5.
Give an example to show that the pollutants studied in this laboratory can
have an effect on the human population. Any one of the pollutants can be used as an
example.
6.
When excess nutrients enter an aquatic ecosystem, long-term effects can
result. Why? Algae overgrow, and when they die, bacteria use up all the oxygen to
decompose them. Organisms that need oxygen die.
61
7.
Describe how the cultural eutrophication supports the hypothesis that a
balance of population sizes in ecosystems is beneficial? Only when algae populations
remain at their normal level can consumers maintain them at a level that will not result
in pollution.
8.
When pollutants enter an ecosystem, they have far-ranging effects. Use acid
rain and a food chain to support this statement. Acid rain can potentially reduce the
size of all populations in any food chain, even humans.
9.
Contrast species composition with species diversity of ecosystems. Species
composition is the number of different species present and species diversity is the number
of each type of species.
10.
Suppose that, among sunflower seeds, a particular variety can germinate
despite acidic conditions. What do you predict about the survival of that sunflower
variety compared to the rest of the population? More and more of this variety will be
present with each passing generation. Evolution has occurred.
62
APPENDIX A
COMMON MATERIALS IN A BIOLOGICAL LABORATORY
Needed Materials
1. Personal safety equipment (Provide or require students to
provide their own.)
safety goggles (See Carolina’s Lab Safety: Face Protection
Section.)
latex gloves or nonlatex gloves (See Carolina’s Lab Safety: Hand Protection
Section.)
lab coats or other clothing protection (See Carolina’s Lab Safety: Body Protection
Section.)
2. Chemical reagents (See Carolina’s Chemistry: Chemicals section.)
3. Distilled water or deionized water (or corresponding solvent) in sufficient
quantity to meet the entire need for the laboratory. Available locally.
4. Test tubes and racks
a. Test tubes. Mini, 12 × 100 mm; Standard, 16 × 150 mm; Medium, 20 × 150 mm;
Large, 25 × 150 mm
b. Test tube racks. Each time students use test tubes, each student station should have
one test tube rack. See Carolina’s Laboratory Equipment and Supplies section for
various styles of racks. Polypropylene racks are clear on top with a white bottom,
to aid in evaluating colors.
5. Microscope supplies
a. slides (glass or plastic)
b. coverslips, plastic
c. cover circles
d. lens paper sheets or lens paper booklets
6. Containers. Stock a sufficient number and size to accommodate the entire volume
of each reagent necessary. See Carolina’s Laboratory Equipment and Supplies
section for the following:
a. beakers, various sizes
b. Pyrex laboratory bottles, 100 ml to 10 liters
c. clear or amber jugs
d. solution bottles, sample bottles, or carboys
e. Erlenmeyer flasks, various sizes
f. graduated cylinder(s), large enough to measure required volumes
g. graduated media bottles, 125 to 1,000 ml
7. Stirring and weighing devices. See Carolina’s Laboratory Equipment and Supplies
section for the following:
a. hot plate stirrer(s)
b. rods, glass stirring
c. Teflon®-coated magnetic spinbar(s)
d. magnetic stirring bar set
e. magnetic stirring bar retriever
f. balances
g. weighing paper(s), nonporous paper (such as xerographic paper cut into small
sheets), plastic weighing boats, or aluminum weighing dishes
63
8. Miscellaneous laboratory supplies
a. transfer pipets
b. dropping bottles. See Carolina’s Laboratory Equipment and Supplies: Bottles.
c. droppers, glass
d. rubber stoppers and corks. See Carolina’s Laboratory Equipment and Supplies:
Stoppers section.
e. spatulas or scoops, one for each type of reagent, or wash and dry between each
reagent. See Carolina’s Laboratory Equipment and Supplies: Spatulas and Tongs
section.
f. labeling tape, labels
g. china/glass pencils, or lab pens
64
APPENDIX B
GENERAL PREPARATION INSTRUCTIONS
Mixture Preparations
1. Label each container.
2. Carefully slide a teflon-coated spinbar down the side of the container. A large
spinbar dropped into a glass container can easily break out the container’s bottom.
3. Weigh each dry reagent, and place it into the correctly labeled container.
4. Measure and add the distilled water to the container, place the container on a hot
plate stirrer, and stir. Heat only if so directed.
5. Once the reagent is completely dissolved and cooled, stopper the container.
6. Most inorganic reagents can be stored indefinitely. Therefore, excess reagents can be
stored for use next term. Most organic reagents should be refrigerated but are
usually stable for one week. Enzymes must be prepared fresh, just prior to each
section, because they are often stable for only a few hours.
Dispensing Reagents
Select one of the following alternatives for dispensing reagents:
1. Label beakers of an appropriate size for corresponding reagents.
2. Label large wash bottles (see Carolina’s Laboratory Equipment and Supplies:
Bottles section) and fill with the corresponding reagents.
3. Use dropping bottles for chemicals that require small quantities (or drops) (e.g.,
iodine solution). See Carolina’s Laboratory Equipment and Supplies: Bottles
section.
Preparation of Boiling Water Bath
Each boiling water bath setup consists of:
• hot plate (See Carolina’s Apparatus: Laboratory Equipment and Supplies: Hot
Plates section.)
• beaker (size varies)
• beaker clamps
• thermometer, Celsius. See Carolina’s Laboratory Equipment and
Supplies: Laboratory Thermometer section.
• test tube clamp (if test tube is being heated)
• boiling chips, pumice
Place a large beaker of water on a hot plate. Adjust the dial on the hot plate so that the
water is maintained at a gentle rolling boil during the experiment. Boiling occurs at
100°C.
Preparing the Laboratory
1. Make a note of the number of students in the current term.
2. Calculate the quantities necessary for the current semester, using the guidelines
given in the next section, Preparations for Mixing. To minimize expense, prepare
only 10% (or 100 ml) more than this amount. Be sure to check the usage rate after
the first or second section to be sure that the last section will have a sufficient
amount of each consumable item.
3. Mix the chemicals according to the preparation instructions given. Be sure to clearly
label each container. Most inorganic reagents can be stored indefinitely; therefore,
excess reagent can be stored for use next term. In general, most stock solutions of
organic reagents should be refrigerated but are usually stable for one week. Most
65
4.
5.
6.
7.
8.
9.
enzymes must be prepared fresh, just prior to each section, because they are often
stable for only a few hours. Refer questions about stability or quantities to an
available instructor or technician.
Check the calendar for any material expected to arrive for the current laboratory, and
for any planting, subculturing, or collecting that needs to be completed during the
week.
Collect the needed materials in a central preparation area. Check off each item with
a diagonal slash (/), indicating that it has been collected. (Note: If material storage
areas are widely scattered, make an additional copy of each individual chapter’s
materials lists and record the room number and shelf or drawer where the materials
are stored. Keep this master list in a three-ringed binder or report folder for quick
reference next term.)
Set up all prepared materials in the laboratory. Attempt to keep all of the material
necessary for a section together, and arrange the material in the sequence
encountered in the exercises. On the individual materials list, circle each item that is
actually placed into the laboratory. This will reduce the chance of some necessary
item being forgotten. Place previously prepared labels by each corresponding group
of materials.
Communicate with all instructors and laboratory assistants regarding the locations of
stock solutions or fresh materials that may be depleted during the course of a
laboratory. In addition, note any sections of the laboratory and materials that have
been omitted and for which there will be no supplies. Communicate this information
by a memorandum given to each involved individual, or by a note taped, in plain
view, to the demonstration table.
Be aware when quantities of dry reagents or consumable materials are low.
Keep a continuously running list of such items, and include items that might be
desirable but not essential.
Keep a loose-leaf notebook, with individual pages for each numbered exercise, and
make notes of any special material needs for each exercise or problems that have
occurred with a given section of the exercise. Often, incorrect reactions are caused
by contamination or spoilage of reagents.
Note: This notebook can also be used to keep the master location list mentioned in
item 5.
Calculate the Total Reagent needed
Calculate the total volume of each reagent necessary for all the laboratory sessions
consulting the preparations sections and multiplying the total number of
students or student groups by the volume needed per student or student groups.
For liquid reagents, round off as per this example:
Example: Round 1,350 ml to 1,400 ml + 100 ml = 1,500 ml
Determine the total number of grams necessary for each dry reagent. (Preparation
instructions for most reagents are listed in grams/100 ml of water or solvent.)
Record.
Record your calculations for each reagent in the blank provided in the “Materials
and Preparations” section. If the number of groups varies between terms, list the
calculation per term (for example, Fall/Winter—Spring/Summer), or enter each
calculation in a different color. Recording these calculations will decrease the
preparation time for subsequent terms.
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Slide-Cleaning Procedures
Possible procedures include:
a. Wash slides prepared from bodily fluids or cells in a 10% bleach solution, rinse,
and dry all slides, and return slides to a designated area; discard plastic coverslips
in a biohazard container.
b. Wash, rinse, and dry all slides, and return the slides to their box; discard plastic
coverslips.
c. Wash and rinse all slides, and place the slides in the drying rack; discard plastic
coverslips.
d. Place dirty slides in the detergent or bleach solution provided; discard plastic
coverslips.
Note: Some institutions prefer that the laboratory assistant wash all slides in an ultrasonic
cleaner, rinse the slides in distilled water, and allow the slides to drain dry.
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