BIOLOGY 201
LABORATORY
MANUAL
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Table of Contents
Laboratory Exercise
Scientific Method and Decision Making
Prokaryotes, Cultures, and Gram Stain
The Excavata
The SAR
The Archaeplastida
The Unikonta
Kingdom Fungi
Kingdom Plantae 1
Kingdom Plantae 2
Kingdome Plantae 3
Kingdom Metazoa 1
Kingdom Metazoa 2
Kingdom Metazoa 3
Kingdom Metazoa 4
Kingdom Metazoa 5
Fetal Pig
Mammalian Diving Response
Page #
3
8
19
21
28
32
34
41
54
66
71
78
85
92
95
105
116
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Scientific Method and Decision Making
Name
AM or PM (circle one)
INTRODUCTION
As you may recall the basic steps in a scientific approach to problem solving includes: a) observe, b) ask
questions, c) formulate a testable hypothesis, d) design and execute a test of your hypothesis, e) analyze
the data generated by the test, e) interpret the results, and f) refine the hypothesis.
Palomar College’s San Marcos campus is found in the middle of an ecosystem described as Coastal
Sage Scrub. Some plants of the coastal scrub practice allelopathy, in which they produce allelotoxins
that inhibit the growth of plant seedlings. In a habitat short on water and soil nutrients, allelopathy
limits competition for these important resources from germinating plants. The fire cycle of the
ecosystem is important because these toxins tend to be heat sensitive. When fire rages through the
coastal scrub it destroys allelotoxins in the soil or leaf litter, creating an opportunity for seeds to
germinate.
The question we are going to consider in the laboratory exercise is this: Does tree tobacco (a common
plant in our local community), Nicotina glauca, possess allelotoxins? To answer this question an
aqueous extract of tree tobacco leaves was prepared by mixing tree tobacco leaves with a volume of
water in a blender and filtering the resulting slurry through cheesecloth. This solution will be used to
test a more specific hypothesis: An aqueous extract of tree tobacco leaves will inhibit the growth of
radish seedlings. This hypothesis will be referred to as the “initial hypothesis” later in the laboratory
exercise.
EXPERIMENTAL DESIGN
Each pair of students will receive two petri plates. About a week ago ten radish seedlings were placed
in each petri plate, and saturated with fluid. One petri plate was saturated with deionized water, and the
other with tree tobacco extract. They have been allowed to grow under artificial light for the last week.
1. Which ten seedlings constitute the control group in this experiment, how is the control group
different from the experimental group?
2. What is the independent or manipulated variable in this experiment?
3. What is the dependent variable in this experiment?
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4. What variables should be held constant for both the experimental and control groups? List as many
as possible.
PROCEDURE
1. As mentioned above, each pair of students will receive two petri dishes of ten radish seedlings--an
experimental group and a control group.
2. Lay each seedling flat on the lab bench and measure its length from root tip to shoot tip in
millimeters (mm). Record the lengths in the table below. Return each seedling to its petri dish. Be
consistent in your technique.
Seedling
Experimental
Control
Group (mm) Group (mm)
Seedling 1
Seedling 2
Seedling 3
Seedling 4
Seedling 5
Seedling 6
Seedling 7
Seedling 8
Seedling 9
Seedling 10
SUM OF SEEDLING
LENGTHS (mm)
MEAN SEEDLING LENGTH
(SUM/10 (mm))
Original Test Statistic (OTS) = |Control mean - Experimental mean| = _______________
Table 1. A comparison of the experimental and control group seedling lengths.
3. After recording the lengths of the seedlings in Table 1, also record the seedling lengths on 3 x 5
cards. Record the experimental seedling lengths on cards of one color, and the control seedling
lengths on cards of another color. Each pair of students will then have ten 3 x 5 cards of one color,
and another set of ten 3 x 5 cards of another color, with each card representing the length of a
particular seedling.
4. Return to Table 1. Add the sum of the lengths of the experimental seedlings, and then divide that
sum by ten to determine the mean experimental seedling length. Repeat for the control group.
5. Next determine the absolute value of the difference between the Control mean, and Experimental
Mean. This value will be called the Original Test Statistic (OTS). Record in the space above.
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ANALYSIS OF DATA
The OTS describes the difference between the experimental and control groups. If the difference was
zero, for example, one might concluded tree tobacco extract has no effect on seedling growth. Likewise,
a number greater than zero suggests tree tobacco extract has an effect. One must be careful not to jump
to conclusions, however. When ANY two sets of data are compared there is (almost) always a
difference. For example if the mean height of one class were compared to another class there would be
a difference. It might be a small, but there would be a difference. The question then becomes, is there a
cause for the difference, or is the difference due to chance, merely a sampling artifact.
Hypothesis formulation.
To help answer the question above, statisticians work with standard hypotheses: the null hypothesis,
and the alternate hypothesis. The null hypothesis (HO) is always the same regardless of the data being
analyzed and can be stated as follows: “The difference between the experimental and control groups is
the product of chance”. Acceptance of the null hypothesis means one is taking the position that any
difference in two data sets is due to chance, a sampling artifact, and is not due to a cause. The alternate
hypothesis (HA) is also always the same and can be stated as: “The difference between the experimental
and control groups is the product of something other than chance.” The “something other than chance”
of the alternate hypothesis means there is a cause for the difference.
In this test, seedlings grown in distilled water were separated from those grown in tree tobacco extract.
There is a difference in the mean length of the two groups, the OTS. What must be considered is this:
What if one had randomly picked ten seedlings from the twenty comprising the experimental and control
groups, and compared their mean length to the remaining ten. Would the absolute value of the
difference be equal to or greater than the OTS calculated by comparing the experimental and control
groups? If this value, known as a Randomized Test Statistic (RTS) was greater than or equal to the
OTS, it demonstrates that it is possible to get differences as great or greater than the OTS due to chance
alone. An RTS smaller than the OTS would indicate that chance, at least in that instance, did not
duplicate the OTS lending credibility to the position that something other than chance (i.e. a cause, the
tree tobacco extract) is responsible for the OTS.
It is important, then, to determine the frequency, or probability, that chance duplicates the OTS. If this
probability is high it is reasonable (defined as 5 or more times per 100) to conclude that the OTS is due
to chance, i.e. that the null hypothesis is true, and that the difference between the control and
experimental groups was not due to the tree tobacco extract, but is merely a sampling artifact.
Conversely, if this probability is low, say less than 5 times per 100, one could reasonably conclude that
the OTS was due to something other than chance, i.e. that the alternate hypothesis is true, and that the
difference between the control and experimental groups was due to the tree tobacco extract.
Randomized Test Statistics
1. Take the twenty cards you created previously and shuffle them several times so that the experimental
and control seedling lengths are thoroughly mixed together.
2. Deal the cards into two piles of ten cards each. There are now two sets of ten cards of mixed colors,
randomly generated.
3. Determine the mean length of the seedlings from each pile.
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4. Subtract the smaller mean from the larger mean to generate a Randomized Test Statistic (RTS).
Record this value, RTS 1, in Table 2.
RTS 1 =
RTS 6 =
RTS 2 =
RTS 7 =
RTS 3 =
RTS 8 =
RTS 4 =
RTS 9 =
RTS 5 =
RTS 10 =
Table 2. Test statistics of randomization test.
5. Repeat steps 1-4 nine more times, generating a total of 10 RTS’s. These can be compared to the
Original Test Statistic (OTS) generated from the experimental and control groups.
6. How many times (out of ten) was the randomized test statistic equal to or greater than, the original
test statistic?
7. Report the results from question 6 to the instructor who will put class totals for following values on
the board. Record those values below.
Class totals
Total number of times the RTS was equal to or greater than, the OTS=
Total number of randomized tests performed by the class (10 x number of pairs in class) =
8. The overall probability that an RTS equaled or exceeded the OTS is calculated as follows (p =
probability):
Total # of times randomized test statistic equaled or exceeded the OTS
p=
Total number of randomized tests performed (#RTS generated)
9. Multiply p times 100 to convert the probability to percent, making it easier to interpret.
p x 100 = %. This value is the frequency or probability that your data is the result of chance, a
sampling artifact.
10. Subtract p from 100 to get the percent confidence that your data is due to a cause, i.e. the tree
tobacco extract. Percent confidence =
%.
Let us return to analysis of the standard hypotheses. At what point should one “draw the line,” so to
speak, and decide whether an experimental result is due to chance or something other than chance.
Biologists generally require a “confidence” of greater than 95% to accept the alternate hypothesis.
This means that to accept the alternate hypothesis randomized results (RTS) must exceed the original
results (OTS) fewer than 5 times per 100 tests (p < .05). This translates to a confidence of greater than
95% and is considered “significant” by the scientific community. When scientist use the phrase “there
is a significant difference…” it means chance duplicates the experimental results less than 5 times per
100 trials (p < .05).
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In our specific case, if less than 5 out of 100 (p < .05) RTS’s equaled or exceeded the OTS, one would
reject the null hypothesis, and accept the alternate hypothesis. If 5 or more out of 100 RTS’s equaled or
exceeded the OTS, the confidence would be 95% or less, and one would accept the null hypothesis and
reject the alternate hypothesis. As one can see, this is a very conservative standard. If the RTS equals
or exceeds the OTS even 5% of the time, then the experimental results are not considered “significant,”
and therefore suspect or unreliable.
STUDY QUESTIONS
1) What is the null hypothesis –quote directly from the laboratory exercise?
2) Do you accept or reject the null hypothesis? Explain your answer.
3) What is the alternate hypothesis--quote directly from the laboratory exercise?
4) Do you accept or reject the alternate hypothesis? Explain your answer.
5) What is the initial hypothesis in this laboratory exercise?
6) Do you accept or reject the initial hypothesis? Explain your answer.
7) If randomization analysis showed that tree tobacco extract inhibited seedling germination, would
that prove that Nicotina glauca leaves possess allelotoxins? Explain your answer.
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Prokaryotes, Cultures, and Gram Stain
1) Background Questions.
a) What is a “bacterial” colony, from what is it derived (in other words, what did it start from)?
b) Must colonies be bacterial? (In other words, are there other types of organisms that from
colonies?)
c) On what type of media do colonies grow?
2) Examination of a broth culture. One method to mass-produce bacteria is to make a broth culture.
A broth culture is produced by inoculating sterile broth with bacteria and incubating at a warm
temperature. Observe a broth culture before incubation and after incubation.
a) Before incubation the broth was clear. After inoculation and incubation the broth is cloudy.
Why is it cloudy?
b) Is growing a broth culture a way to grow large numbers of bacteria, or a way to separate
individual bacteria from one another? Explain your answer.
c) Are individual colonies observed in a broth culture? Explain.
3) Observation of a smear plate. Another method to mass-produce bacteria is by growing them on a
nutrient agar petri plate in what is called a smear or spread (in a similar technique) plate.
a) Observe a smear plate provided to you (and/or the photograph below) and answer the following
questions.
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i) Do you see individual colonies or have colonies grown together to form a mass of bacteria?
ii) Is preparing a smear plate a way to mass produce bacteria, or a way to separate individual
bacteria from one another? Explain your answer.
iii) Why make smear plates instead of broth cultures and vice versa? What are the advantages
and disadvantages of each?
4) Observation of a streak plate. Streak plates are used to isolate single bacteria, and allow them to
divide to form a colony of genetically identical bacteria. These isolates can then be further cultured
and characterized.
a) Observe streak plates and answer the following questions.
i) Do you observe individual colonies?
ii) Bacteria cannot digest agar. Why is this important to isolation of individual colonies of
bacteria?
iii) Agar is about 99% water. Why should agar petri plates be stored upside down?
b) Examination of colony characteristics. Some bacteria can be identified by the colony
characteristics when grown on specific types of media. Colonies are described according to their
shapes, margins (edges), and surfaces (see figure 12.1 on the next page).
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c) Determine how many different types of bacteria are growing on the streak plate. Put the number
in the space below.
d) How many types of bacteria do you see growing on the streak plate picture below?
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5) Examination of a slant culture. Another way to grow bacteria is on a slant of agar. Observe the
slant cultures and the pictures below.
Does a slant culture look like it is used to isolate individual colonies or to mass produce bacteria?
Explain.
6) Microscopic examination of prepared bacterial slides (gram stain). Be sure to thoroughly clean the
slide with an alcohol swab and paper towel before returning it to its slide box. (Refer to page 29 of
the Photographic Atlas.)
a) Directions for microscopic observation of bacterial slides. Begin focusing with the scanning
objective (4X), move to the low power objective (10X), and high-dry objective (40X). Be sure
to use only the fine adjustment knob when using the high-dry objective. Once you have a clear
focus on high dry, turn the revolving nosepiece halfway between the high-dry objective and the
oil objective (100X) and put a drop of optical quality oil on the surface of the prepared slide.
Then continue turning the nosepiece until the oil objective locks in place. Carefully, using only
the fine adjustment knob, bring the slide and objective closer together until the bacteria come
into focus. Complete the information below.
b) Pseudomonas aeruginosa (below)
i) Domain:
ii) Phylum:
iii) Shape:
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c) Bacillus (above)
i) Domain:
ii) Phylum:
iii) Shape:
d) Escherichia (E. coli, below)
i) Domain:
ii) Phylum:
iii) Shape:
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e) Staphylococcus (above)
i) Domain:
ii) Phylum:
iii) Shape:
7) What is total magnification (ocular lens power x objective lens power) for:
a) Scanning power—
b) Low power—
c) High-dry power—
d) Oil immersion—
8) What is the field of view diameter at the following magnifications:
a) Scanning power = 5.0 mm =
b) Low power = 2.0 mm =
c) High-dry power = 0.5 mm =
d) Oil immersion = 0.2 mm =
um
um
um
um
9) Estimate the size of the specimen below in micrometers (um) if viewed at low power. Show all
work.
Specimen
?
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10) Suppose one person is looking at a specimen (A) with the scanning power lens. The specimen's
length is about one-tenth (10%) of the field of view diameter. Another person is looking at a
specimen (B) with the low power lens. That specimen's length is about one-third (33%) of the field
of view diameter. Which specimen, A or B, is longer? SHOW THE MATH FOR EACH
SITUATION TO ANSWER THE QUESTION.
11) Observe Cyanobacteria at 1000x. Refer to page 29-34 of the Photographic Atlas.
a) Observe a prepared slide of Gleocapsa, pictured below. Label the following: capsule.
b) Classify to phylum.
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c) Observe a prepared slide of Anabena, pictured below. Label the following: Heterocyst,
vegetative cell. What is the function of the heterocyst?
d) Classify to phylum.
e) Observe a prepared slide of Oscillatoria, pictured below. Label the following: Vegetative cell,
Hormogonium, Separation disc.
The separation disk is a weak spot in the filament. What function might it serve?
f) Classify to phylum.
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12) Preparation of a gram stain. Morphological identification of bacteria has limitations, so
biochemical techniques are used. A simple method to distinguish bacteria biochemically begins
with cell wall composition and the stains they bind. The gram stain detects the presence of a
particular type of cell wall. Gram-positive bacteria have a thick peptidoglycans layer in their cell
wall. This layer retains crystal violet in gram stain, and stain purple. The gram negative bacteria
have a thin layer of peptidoglycans as well as a number of lipids, and does not hold crystal violet but
does counter stain with safranin, looking pink or red under the light microscope.
a) Arrange yourself in groups of four. Two of you will prepare gram strains of Bacteria A and two
of you will prepare gram stains of bacteria B.
b) Obtain a glass slide, a slant culture of Bacteria A or Bacteria B, a wire loop, staining tray, gram
stain sets, bibulous paper, clothespin.
c) Put a small drop of water on the glass slide.
d) Ignite a Bunsen burner as instructed, and hold the loop in the flame until it glows red (flaming
the loop).
e) Take the loop out of the flame, and quickly unscrew the top on the slant culture.
f) While keeping the cap in your hand, quickly pass the opening of the slant culture through the
flame a couple of times.
g) Let the loop cool slightly, test in a small section of the agar, and then take a small scraping of
bacteria from the surface of the slant—LESS IS MORE!
h) Quickly pass the opening of the slant through the flame, and screw lid back on.
i) Mix bacteria from your loop in with the water to make a film on the glass slide, again, LESS IS
MORE!
j) Flame the loop.
k) Disinfect any contaminated surfaces.
l) Let slide air dry.
m) Using the clothespin, hold slide at 45-degree angle and over flame several times. You want to
warm the slide, but not cook the bacteria.
n) Put slide on staining tray.
o) Cover smear with crystal violet and wait 2 minutes.
p) Gently rinse with distilled water in squirt bottle.
q) Cover smear with gram iodine for 1 minute, pour off excess and let stand another minute.
r) Gently rinse with water and gently blot with bibulous paper.
s) Hold the slide at an angle and gently rinse slide with 95% ethanol a drop at a time until color
stops running from the smear—be careful not to overdo.
t) Gently rinse with water and blot with bibulous paper.
u) Cover smear with safranin for 30-60 seconds.
v) Rinse briefly, and blot delicately with bibulous paper.
w) Let air-dry.
x) Examine the slides of Bacteria A and Bacteria B under oil objective without a cover slip.
y) Complete the information below using your book and lecture outline.
z) Discard slides in Sharps container when done.
aa) Directions for microscopic observation of bacterial gram stains. NO COVERSLIP IS USED
WHEN OBSERVING GRAM STAINS. Begin focusing with the scanning objective (4X), move
to the low power objective (10X), and high-dry objective (40X). Be sure to use only the fine
adjustment knob when using the high-dry objective. Once you have a clear focus on high dry,
turn the revolving nosepiece halfway between the high-dry objective and the oil objective
(100X) and put a drop of optical quality oil on the surface of the prepared slide—REMEMBER,
NO COVERSLIP IS USED WHEN OBSERVING GRAM STAINS. Then continue turning the
nosepiece until the oil objective locks in place. Carefully, using only the fine adjustment knob,
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bring the slide and objective closer together until the bacteria come into focus. Complete the
information below.
bb) Discard the slides when everyone in your group is done with them.
i) Bacteria A
(1) Domain:
(2) Phylum:
(3) Shape:
ii) Bacteria B
(1) Domain:
(2) Phylum:
(3) Shape:
Do you think morphology would be more useful in classifying prokaryotes at the phylum level or
species level? Explain.
13) THOUROUGHLY CLEAN OIL FROM ALL MICROSCOPIC LENSES AND SLIDES. USE
ALCOHOL WIPES AND LENS PAPER ON LENSES, ALCHOHOL WIPES AND
KIMWIPES ON MICROSCOPE HARDWARE AND SLIDES. SHOW YOUR
INSTRUCTOR YOUR MICROSCOPE BEFORE PUTTING THE MICROSCOPE AWAY.
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The Excavata
***Note the Photographic Atlas (pages 35-66) is slightly outdated for the taxonomy of the Protists. If
there is a discrepancy use the taxonomy presented in lecture.
1.
Examine a slide of Giardia. Be able to identify Giardia trophozoites
a)
Classify to supergroup and phylum (you’ll have to look the phylum up).
b)
What sort of disease does Giardia cause?
2.
3.
Observe a prepared slide of Trypanosoma with the oil objective. Refer to page 42 of the
Photographic Atlas.
a)
Identify the following on the figure below: erythrocyte, trypanosome, flagellum.
b)
Classify to phylum and class (go by the lecture notes).
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c)
4.
5.
Is Trypanosoma more closely related to Giardia or Plasmodium?
If available, your instructor will prepare a wet-mount slide of a termite’s gut to observe live
Trichonympha organisms. Make a diagram in the space below. Label the following (flagella,
nucleus, wood chips) and answer the questions below.
a)
This organism is a member or the: Excavata or SAR? (circle the correct answer).
b)
What is a mutualism?
c)
Describe the mutualistic relationship between the Trichonymphs, termite, and bacteria.
(What does each party in the relationship get that is beneficial?)
d)
How are Trichonympha morphologically different from most Excavates?
Observe a prepared slide of Euglena and identify the following structures on the figure below:
nucleus, cell wall. Refer to page 42 of the Photographic Atlas.
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a)
Classify to phylum and class.
The SAR
1. Observe prepared slides of Foraminiferans, make a drawing of one of these organisms.
a. Of what are the shells composed?
b. Do these organism use pseudopodia?
c. Are they zooplankton or phytoplankton?
d. Classify to phylum.
e. This organism is a member of the: Stremenopiles, Rhizaria, or Alveolata? (circle the correct
answer)
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2. Observe prepared slides of Radiolarians and make a drawing. (Note: These organisms are often
confused with diatoms. Annotate your drawing with some observations that will avoid this mistake.)
a. Of what are the shells composed?
b. What are pseudopodia used for in this organism?
c. Describe how this organism displays both plant and animal characteristics.
d. Are these organisms more closely related to Foraminifera or diatoms?
3. Observe a live Paramecium if available. Refer to page 43 of the Photographic Atlas.
a. Diagram a single Paramecium in the space below and label the following if visible:
contractile vacuole, cilia, macronucleus, pellicle, oral groove. You may use a figure from
lecture or Campbell to help. The contractile vacuole will probably be difficult to see.
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b. Observe a prepared slide of Paramecium and identify the following structures on the diagram
below: cilia, macronucleus, micronucleus (if visible).
c. What is the ploidy of the macronucleus and micronucleus?
d. Be able to describe how they sexually and asexually reproduce (refer to Campbell).
e. Classify to phylum.
f. This organism is a member of the: Stremenopiles, Alveolata, or Rhizaria? (Circle the
correct answer.)
g. What does the contractile vacuole do (refer to Campbell)?
h. Is this organism more closely related to the Apicomplexa or Euglenozoa?
4. Observe live Stentor if available and make a drawing below. Label the following: cilia,
macronucleus, and gullet and stalk. Refer to page 44 of the Photographic Atlas.
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a. Identify the following on a prepared slide of Stentor and label on the figure below: cilia,
macronucleus, and gullet, stalk.
b. Classify to phylum.
c. This organism is in the same phylum as Paramecium and yet looks very different. What
characteristic do they have in common?
5. Observe live Vorticella if available and make a drawing below. Label the following: cilia,
macronucleus, and gullet.
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a. Identify the following on a prepared slide of Vorticella and label on the figure below: cilia,
macronucleus, and gullet, stalk.
b. Classify to phylum.
c. How does this organism feed?
6. Observe a prepared slide of Plasmodium vivax or P. falciparum with the oil objective. Identify the
following on the figure below: erythrocyte, merozoites. Refer to page 42 of the Photographic Atlas.
a. What disease is caused by this parasite?
b. Be able to describe the life cycle of this parasite.
c. Classify to phylum.
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d. This organism is a member of the: Stremenopiles, Alveolata, or Rhizaria? (Circle the
correct answer.)
7. Observe prepared slides of the sexual phase of the water mold, Saprolegnia.
Label the following: hypha, oogonium, oospores. Refer to pages 65-66 of the Photographic Atlas.
a. Classify to phylum (know both names associated with this phylum) and class.
b. What is the ploidy of the hypae ? (Consult the lifecycle from Campbell or the Photographic
Atlas.)
c. What is the ploidy of the oospores?
8. Observe diatoms and make a drawing. Refer to pages 37-38 of the Photographic Atlas. Label the
following: valve, nucleus (The nucleus will not be visible in the prepared slides, but may be in live
diatoms, if available.)
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a. Classify to phylum and class.
b. Is this organism more plant-like or animal-like?
c. What triggers sexual reproduction in diatoms, and be able to describe their life cycle?
9. Observe prepared slides of dinoflagellates and make a drawing. Refer to page 40 of the
Photographic Atlas.
a. Classify to phylum.
b. Is this organism a member of the SAR or the Excavata? (circle one)
c. Is this organism more closely related to Plasmodium or Euglena?
d. How does this organism exhibit both plant-like and animal-like characteristics?
e. Why are they a concern if you are a beachgoer or shellfish consumer?
10. Observe specimens of brown algae and answer the following. Refer to pages 55-59 of the
Photographic Atlas.
a. Label the following on the figures below: holdfast, stipe, blade, pneumatophores.
b. Classify to phylum and class.
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c. Of what commercial value are members of this phylum?
d. How is this organism different from most other “Protists”?
e. In what ways are these organisms different from true plants?
f. Draw the lifecycle of a typical Phaeophyte. Use Campbell or the Photographic Atlas if
necessary. (Note: This is a good example of alternation of generations)
The Archaeplastida
1. Observe specimens of red algae. Refer to pages 60-62 of the Photographic Atlas.
a. Label the following on the specimens below: stipe, blade.
b. Classify to phylum
c. Of what commercial value are members of this phylum?
d. Why are red algae often found in deep water?
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The Plantae (Kingdom)
Refer to page 44-54 of the Photographic Atlas.
1. Which Protist divisions (phyla) constitute the “green algae”?
2. Which Protist divisions (phyla) are often included in Kingdom Plantae along with the land
plants?
3. Which Protist division (phylum) is the closest relative to land plants?
4. Observe prepared slides (or live organisms if available) of the colonial green alga, Volvox.
a. Identify the following on the figure below: Parent colony, daughter colonies, zooids.
b. Classify to kingdom and phylum.
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5. Observe mounts of the multicellular green alga, Ulva. Refer to page 53 in the Photographic
Atlas.
a. Classify to kingdom and phylum.
6. Observe prepared slides (and live organisms if available) of the filamentous green algae,
Spirogyra, vegetative. Refer to pages 50-51 in the Photographic Atlas.
a. Identify the following on the figure below: cell wall, nucleus (if visible), chloroplasts.
b. Classify to kingdom and phylum.
c. Are the filaments haploid or diploid? (Consult the lifecycle in the Photographic Atlas)
d. Why is this phylum considered closely related to land plants?
7. Observe prepared slides of the filamentous green algae, Spirogyra, in conjugation (sexual phase).
a. Make a drawing of this organism and label the following: cell wall, conjugation tubes.
8. Observe prepared slides of the filamentous green algae, Ulothrix. Refer to page 47-48 in the
Photographic Atlas.
a. Identify the following on the figure below: cell wall, nucleus (if visible), chloroplast.
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b. Classify to kingdom and phylum.
9. Observe Desmids. Refer to page 53 in the Photographic Atlas. Note Desmids are Charophytes.
a. Observe and draw live organisms if available. Label the following: cell wall, chloroplast,
isthmus, terminal vacuole.
b. Observe a prepared slide of Desmids and label the following on the figure below: cell
wall, nucleus (if visible). Chloroplasts and terminal vacuole are visible on some prepared
slides.
c. Classify to kingdom and phylum.
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The Unikonta
1. Observe a live Amoeba or Chaos if available and make a drawing below. Label the following:
pseudopod, contractile vacuole (if visible), nucleus, and cytoplasmic granules (vesicles). Refer
to page 41 in the Photographic Atlas.
2. Be able to identify the following on a prepared slide of Amoeba or Chaos and the figure below:
pseudopod, nucleus, and cytoplasmic granules (vesicles).
a. How are the pseudopodia in this organism different from those found in the Rhizaria?
b. What are pseudopodia used for in this organism?
c. Classify to phylum.
d. Is this Protist more animal-like or plant-like?
3. Observe petri dishes of the acellular (plasmodial) slime mold. Refer to pages 63-64 in the
Photographic Atlas
a. What is the genus of the specimen? (Read directly off the plate.)
b. Observe the specimen under a dissecting scope and observe streaming protoplasm.
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c. Classify to phylum.
d. How might you determine whether a slime mold is a cellular slime mold, or an acellular
(plasmodial) slime mold?
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Kingdom Fungi
1. Observe a petri plate of growing black bread mold (Rhizopus) with the dissecting microscope.
Refer to page 136-137 of the Photographic Atlas. Be able to identify: hyphae, mycelium,
zygosporangia.
2. Observe a prepared slide of Rhizopus vegetative with sporangia with a compound microscope.
Refer to page 136-137 in the Photographic Atlas. Make a drawing in the space below and label
the following: hypha, sporangiophore, sporangium, spores.
In addition, here are some photographs to help your studying.
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3. Observe a prepared slide of black bread mold, Rhizopus, (sexual or with zygospores) with the
compound microscope. Refer to page 136-137 of the Photographic Atlas. Label the following
on the figure below: hyphae, zygosporangium w/zygospores, suspensor cells.
a. What is the relationship of hyphae to a mycelium?
b. Classify to phylum.
c. Diagram the life cycle of Rhizopus (see Campbell or Photographic Atlas)
d. Determine the ploidy of the following Rhizopus structures:
i. Mycelium hyphae.
ii. Zygosporangium (the exterior).
iii. Zygospores.
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4. Observe a mushroom with the naked eye and dissecting microscope. Refer to page 142-143 in
the Photographic Atlas.
a. Make a drawing and label the following: basidiocarp, pileus, stipe, annulus, lamellae
(gills). What is the ploidy for each of these structures?
In addition, here are some photographs to help your studying.
b. Classify to phylum.
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5. Observe a prepared slide of a cross section of a mushroom (Coprinus) lamella with a compound
microscope. Refer to page 144 in the Photographic Atlas.
a. Label the following on the figure below: lamella (gill), basidium, sterigma, and
basidiospores.
b. Draw the Basidiomycota lifecycle (see Campbell or Photographic Atlas).
c. Determine whether each of the following is haploid, diploid, or dikaryotic.
i. Soil hyphae/mycelium.
ii. Basidiocarp.
iii. Basidium.
iv. Basidiospores.
d. Observe all specimens of Basidiomycota available to you. Make drawings if you find it
helps you study. Taking photos is fine too.
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6. Observe a prepared slide of Penicillium. Refer to page 141 of the Photographic Atlas.
a. Make a drawing and label the following: hyphae, conidiophores, and conidia
(conidiospores).
In addition, here is a photograph to help your studying.
b. Classify to phylum.
7. Observe a prepared slide of Aspergillus. Refer to page 141 of the Photographic Atlas.
a. Make a drawing and label the following: hyphae, conidiophores, and conidia
(conidiospores).
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In addition, here is a photograph to help your studying.
b. Classify to phylum.
8. Observe a prepared slide of the cup fungus, Peziza. Refer to pages 138-140 in the Photographic
Atlas.
a. Label the following on the figure below: hyphae, hymenial layer, ascus (ascosporangium)
and ascospores.
b. Classify to phylum.
c. What is the common name of the specimen below? Classify to phylum.
d. Observe all examples of Ascomycota available in lab
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9. Observe a prepared slide of the lichen Physcia. Refer to page 147 in the Photographic Atlas.
a. Label the following on the figures below: hyphae, algal cells, ascus (ascosporangium),
and ascospores.
b. Classify the fungus to phylum.
c. What characteristic did you use to make this classification?
d. What types of algae and bacteria are commonly found in lichens?
e. Observe specimens of lichens and classify as crustose, fruitcose, or foliose (Refer to page
80 of the Photographic Atlas), and label those picture below accordingly (Note: there is a
mistake in the atlas; do not let this confuse you.)
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Land Plants (Kingdom Plantae) Part 1
Nonvascular and Vascular-Seedless Plants
1) Obtain a sample of living moss or a preserved specimen. Refer to pages 74-76 in the Photographic
Atlas. Identify on the following on your specimen and on the figures below: gametophyte,
sporophyte, capsule, 1n, 2n.
a) On one of the diagrams above indicate where the archegonia were located?
b) What is the ploidy of the moss gametophyte?
c) What is the function of the gametophyte in the moss life cycle?
d) What is the ploidy of the sporophyte?
e) What is the function of the sporophyte?
f) Does the moss have veins?
g) How are the mosses anchored in the soil? What are these structures called?
h) In what sorts of environments are mosses found and why are they found there?
i) Can mosses get as tall as a tree? Explain.
j) Classify the moss to phylum.
k) Gametes are produced within structures called gametangia (“gamete bearers”) at the tips of the
“leafy” moss sprigs (gametophyte). How do sperm released by antheridia get to the ova within
the archegonia housed at the tips of other sprigs of moss?
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2) Observe slides labeled Moss (Mnium) Antheridial Head, and Moss (Mnium) Archegonial Head.
These slides are sections through the moss gametophyte, showing the gametangia. Refer to page 77
of the Photographic Atlas. Make drawings of each and identify the following structures:
antheridium, archegonium, ovum and paraphyses.
In addition, here are some photographs to help your studying.
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a) Once an ovum is fertilized at the tip of a moss gametophyte, it is a zygote. What is the ploidy of
a zygote?
b) Into what will the zygote develop?
3) Obtain a prepared slide labeled “Moss capsule”, or “Moss mature capsule.” Observe low power.
This sporangium is where the sporophyte makes its spores to continue the life cycle. Refer to page
77 in the Photographic Atlas. Make a drawing and label the following structures: capsule,
operculum, spores, columella.
In addition, here are some photographs to help your studying.
a) What is the ploidy of the cells of the sporangium/capsule? Hint: the sporangium is part of the
sporophyte.
b) What is the ploidy of the spores?
c) Into what will the spores develop?
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4) Observe a prepared slide labeled “Moss protonema.” Refer to page 76 of the Photographic Atlas.
These slides show the “baby gametophyte”, called a protonema or protonemata, germinating from
spores. Label the following on the figure below: protonema and bulbil.
a) What is the ploidy of the protonema, and into what will it develop?
b) Bryophytes are described as being “gametophyte dominant.” Why are they described this way—
what does the term mean?
5) Obtain a live or preserved sample of a liverwort. Refer to pages 70-72 in the Photographic Atlas and
label the following structures on the figure below: antheridiophore, archigoniophore, gametophyte,
sporophyte, gemmae cups. Where are the antheridia and archegonia located? Which structures are 1n
and which are 2n?
a) Classify to phylum.
b) Are roots and veins are present? Explain.
c) How do liverworts and mosses obtain nutrients from their environment?
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6) Observe prepared slides of Liverwort (or Marchantia) antheridia (or antheridophore). Refer to page
72 of the Photographic Atlas. Make a drawing and label the following: antheridiophore and
antheridium.
In addition, here are some photographs to help your studying.
a) What is the ploidy of the antheridiophore? The sperm?
b) How do the sperm get from the antheridia to the archegonia and ova (egg)?
7) Observe prepared slides of Liverwort (or Marchantia) archegonia (or archegonioophore). Refer to
page 72 of the Photographic Atlas. Make a drawing and label the following: archegoniophore,
archegonium, ovum.
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In addition, here are some photographs to help your studying
a) What is the ploidy of the archegonium? The ovum?
b) Into what does the zygote develop?
8) Observe a prepared slide of a liverwort (Marchantia) sporophyte. Refer to page 72 of the
Photographic Atlas. Label the following structures on the figures below: sporophyte, sporangium,
spore, seta, foot. Which structures are 1n and which are 2n?
a) Where is the sporophyte located on a liverwort?
b) What is the ploidy of the seta? the spores?
c) What process generates the spores and where are they produced?
d) What do the spores germinate into? (What do they produce?)
e) Are liverworts gametophyte dominant or sporophyte dominant? Explain.
f) Are Mosses and Liverworts seed producing plants? Explain.
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9) Observe a prepared slide labeled “gemma cups”. Refer to page 71 in the Photographic Atlas.
Identify the following structures on the figures below: gemmae cup (or cupule), and gemmae.
a) The gemmae are small pieces of tissue that are produced asexually and wash out of the cup in the
presence of water. What might be their purpose?
b) What is the ploidy of the gemmae?
10) Club mosses. Refer to pages 78-79 in the Photographic Atlas. Classify to phylum.
a) Observe live or preserved specimens of Lycophyta and label the following on the figures below:
strobilus, sporophylls, leaves.
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i) Are these plants vascular or nonvascular plants?
ii) Are the leaves of this plant considered microphylls or megaphylls? Why?
iii) Where are spores produced in these plants?
iv) Are you looking at the gametophyte or sporophyte? What is its ploidy?
v) Are these seed producing plants?
vi) What substance is required for fertilization?
vii) Are the Lycophyta sporophyte dominant or gametophyte dominant?
b) Observe live specimen of Selaginella. Classify to phylum.
c) Observe a prepared slide of longitudinal section of a Selaginella strobilus. Refer to pages 80-81
in the Photographic Atlas. Make a drawing and identify the following structures: strobilus,
sporophyll, microspores, megaspores, megasporangium, microsporangium, cone axis.
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In addition, here are some photographs to help your studying.
i) What is the ploidy of the strobilus.
ii) What is the ploidy of the spores?
iii) Into what will a microspore develop?
iv) Into what will a megaspore develop?
11) Observe the live Horsetail specimen. Classify to phylum (go by the taxonomy presented in lecture).
a) Observe live or preserved specimens of Equisetum. Refer to pages 85-86 in the Photographic
Atlas. Label the following on the figures below: nodes, strobilus, sporophyll, sporophyte.
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b) Are these vascular or nonvascular plants?
c) Where does photosynthesis occur on this plant (which plant-parts)?
d) Are you looking at the sporophyte or gametophyte? What is its ploidy?
e) What is the function of the strobilus, of what is it composed?
f) Is this plant sporophyte dominant or gametophyte dominant? Explain.
g) Are these seed producing plants?
12) Ferns. Classify to phylum (go by the taxonomy presented in lecture).
a) Look at a fern frond. Refer to pages 88-90 in the Photographic Atlas. Make a drawing and label
the following structures: pinna, sorus.
In addition, here is a photograph to help your studying.
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b) Are ferns vascular or nonvascular?
c) Are fern fronds considered microphylls or megaphylls? Why?
d) Are the pinna sporophyte or gametophyte tissue?
e) Observe the undersurface of one of the leaflets of the fern frond with the dissecting microscope.
You should see small oval or round structures called sori (singular = sorus). A sorus is a cluster
of sporangia. Try to observe the individual sporangia with the dissecting microscope. Refer to
page 90 of the Photographic Atlas
13) Obtain a prepared slides labeled “Fern sori, w.m.,” and “Fern sorus, l.s.” and “Fern sporangia, w.m.”
Observe with the compound microscope and label the following structures on the figures below:
sorus, pinna, indusium, sporangium, annulus, stalk, spores. Refer to page 90 in the Photographic
Atlas.
a) What is the ploidy of the fern pinna?
b) What is the ploidy of the sporangium?
c) What is the ploidy of the spores?
d) By what process are the spores produced?
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e) How are the spores disseminated?
f) Into what will the spores develop?
14) Observe a prepared slide labeled “Fern prothallium, archegonia” or “Fern archegonia,” and “Fern
prothallium, antheridia”. Refer to page 91 in the Photographic Atlas. Make drawings and label the
following structures: archegonia, antheridia, sperm, ovum (you will not be able to see sperm and
ovum, but note which structure each would be in), and rhizoids.
In addition, here are some photographs to help your studying.
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a) What is the ploidy of the gametophyte?
b) From what did the gametophyte develop? (What produced it?)
c) What important cells will the gametophyte produce?
d) How do sperm produced by “male” gametophytes get to ova housed in archgonia of female
gametophytes?
e) Where will the zygote be found?
f) Into what will the zygote develop?
15) Obtain prepared slides labeled “Fern prothallium with sporophyte,” and observe with the compound
microscope. Label the following: sporophyte, gametophyte, 1n, 2n.
a) From what did this young sporophyte develop?
b) What is the ploidy of the sporophyte?
c) What will happen to the gametophyte?
d) Do ferns produce seeds?
e) Are ferns sporophyte dominant or gametophyte dominant? Explain.
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Land Plants (Kingdom Plantae) Part 2
Gymnosperms and Angiosperms
1. Examine either a potted cycad or one outside the Natural Sciences building. Refer to pages 9296 of the Photographic Atlas.
a. Classify to phylum.
b. Why are they considered gymnosperms?
c. What is the common name for Cycads?
d. Look at the cone of a cycad. Is it a male cone or a female cone?
e. Are cycads monecious or dioecious?
f. Label the following on the figures below: sporophyte, strobilus, sporophyll
g. Is the strobilus a megastrobilus or a microstrobilus? How can you tell?
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2. Examine the Ginkgo specimens. Refer to pages 97-98 in the Photographic Atlas. Label the
following on the figures below: leaf, seed, ovules, microstrobilus, microsporophyll.
a. Classify to phylum.
b. Do Ginkgos produce female cones? Explain
c. Where is the female gametophyte (megagametophyte) on the figures above.
3. Phylum Gnetophyta—observe and specimen of Ephedra. A photograph is provided below.
a. Classify to phylum.
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b. Are you looking at the sporophyte or gametophyte?
4. Imagine, or look at a pine tree. Refer to pages 99-105 in the Photographic Atlas.
a. Are the leaves, trunk, bark, roots, etc. part of the sporophyte or gametophyte? What is
the ploidy of the pine tree?
b. Classify to phylum.
5. Observe male and female cones. Label the following on the figures below (some of these terms
are redundant): megastrobilus, microstrobilus, staminate cone, ovulate cone, megasporophyll,
microsporophyll, first year cone, second year cone.
a. Indicate where seeds are/would be located on a female cone above. How many seeds are
produced per sporophyll (look at seed impressions or seeds themselves if present)?
b. Within the microsporophylls meiosis occurs generating numerous “microspores,” or
immature pollen grains.
i. What is the ploidy of a microspore?
ii. Into what does any spore, including a microspore, develop?
c. Each microspore divides to form a two-celled microgametophyte or male gametophyte.
We call these microgametophytes, mature pollen grains. If you see yellow granules in
and around scales of the male cone, these are pollen grains.
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6. Observe a prepared slide labeled “Pinus median male cone (or strobilus)”. Start on scanning
power, and work your way up to high-dry to examine the pollen grains. Refer to page 104 in the
Photographic Atlas. Label the following on the figures below: microstrobilus, staminate cone,
cone axis, microsporophyll, microspore, microgametophyte, immature pollen grain, mature
pollen grain, tube nucleus, generative nucleus, wing. (Some of these terms may be redundant.)
a. What is the ploidy of the pollen grains?
b. If the pollen grains are microgametophytes, what gamete will they produce for the life
cycle to continue?
c. What structure of the pollen grain suggests they are carried by wind as opposed to
insects?
d. What is the purpose of the tube nucleus?
e. What is the role of the generative nucleus?
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7. Observe a slide labeled “Pinus ovulate cone.” This is a young female cone, also part of the
sporophyte. Notice the scales and a round mass of cells at the base of each scale. This mass is
known as the ovule. Within the ovule, meiosis will generate a single “megaspore” or female
spore, which will develop into the female gametophyte (megagametophyte). The female
gametophyte will produce a single ovum. Refer to page 103 in the Photographic Atlas. Make a
drawing of a single scale and ovule, and identify the following structures: megasporophyll,
ovulate cone, megastrobilus, ovule, integument, megagametophyte. (Some of these terms may be
redundant.)
In addition, here are some photographs to help your studying.
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a. What is the ploidy of the cone (it is part of the sporophyte)?
b. What is the ploidy of the cells of the ovule (they are also part of the sporophyte)?
c. What is the ploidy of the megaspore?
d. Is the megaspore released or held within the cone?
e. Where does the megaspore develop into a gametophyte?
f. What gamete must the female gametophyte produce for the life cycle to continue?
g. Why is water not needed for fertilization in conifers?
h. How has this adaptation allowed plants to exploit a greater range of habitats?
i. Is the female gametophyte ever free-living on its own, or is it always encapsulated by the
sporophyte tissue of the female cone?
j. What is the ploidy of the zygote, and where physically on the pine tree is the zygote
found?
k. What is the ploidy of the embryo, and where physically on the tree is the embryo found?
l. Is the embryo a new sporophyte or gametophyte?
m. If pollen from a male cone on a tree pollinated and fertilized an egg in a female cone on
the same tree has sexual reproduction occurred, or is this a type of asexual reproduction?
Explain your reasoning.
n. How might conifers prevent self-fertilization?
o. The microgametophytes and megagametophtes are describe as “parasitic” in conifers.
What does this mean?
p. The embryo in the seed develops from the zygote as previously described. The food
reserves of the seed develops from surrounding gametophyte cells.
i. What is the ploidy of the food reserves in the gymnosperm seed?
ii. What is the ploidy of the seed coats of the gymnosperm seed?
iii. Physically, where is the gymnosperm seed found on the conifer tree?
q. Observe typical conifer leaves. Describe the leaf.
r. What would be the advantage of having needles instead of broad leaves? The
disadvantages?
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s. Note that the leaves are found in bunches called fascicles. The numbers of needles per
fascicle is a key in classifying conifers. How many needles per fascicle in the specimen
provided?
8. Observe a flower model. Refer to page 119 in the Photographic Atlas. Identify the following
structures and label on the figure below: sepal, petal, receptacle, pistil/carpel, stigma, style,
ovary, ovule, stamen, anther, filament, pollen grains, pollen tube, micropyle. (Note: The “pistil”
is the collection of all the carpels; some flowers have more than one carpel; all the carpels
together is referred to as the pistil)
a. What is the relationship between petals, sepals, corolla, and calyx?
b. Does the model show a superior ovary or inferior ovary? (refer to page 119)
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9. Observe a slide labeled “Lilium anther”. Refer to page 127 in the Photographic Atlas. Label the
following structures on the figures below: microspores, pollen grains (look for two nuclei),
anther wall, filament
a. How do you tell a microgametophyte from a microspore?
b. Name the nuclei in a microgametophyte.
c. What is the function of the tube nucleus?
d. What is the function of the generative nucleus?
10. Obtain a prepared slide labeled “Lilium 8 cell embryo sac” and refer to pages 127-128. Label the
following structures on the figures below: megagametophyte, ovule, micropyle, integument,
ovary wall, funiculus, and locule. If you visible, see if you can make out some of the specialized
cells of the megagametophyte: egg, synergids, polar nuclei.
a. What is the ploidy of the integument, megagametophyte, and funiculus?
b. Is Lilium a gymnosperm or angiosperm? Classify to phylum.
c. The individual oval structures within the ovary are ovules. What does each ovule
develop into? What does the ovary develop into?
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11. Obtain a Gladiola flower. Refer to page 121 of the Photographic Atlas. Dissect the flower so
you separate the sepals, petals, and stamens from the pistil. Make a cross section or longitudinal
section through the ovary to observe the ovules within. Observe the following structures and
label on the figures below: sepal, petal, carpel, stigma, style, ovary, receptacle, anther, filament,
and stamen, ovule, funiculus, locule.
a. Classify the Gladiola to phylum.
b. How do you know whether it is a monocot or eudicot?
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12. Input the Gladiola (a monocot) information below. Ask the instructor whether a eudicot species
of flower is available for inspection—if so record its information below as well. Carpels are
often fused so the cross section through the ovary of the flower will help you determine how
many carpels are present.
Monocot
Eudicot
Sepals (Calyx)
Petals (Corolla)
Stamens
Stigmas
Carpels
Leaf venation
13. Look at the head of a member of the flower family, Compositaceae, such as a sunflower or daisy.
Refer to page 123 of the Photographic Atlas. Note that it is not a single flower but a collection
of dozens of flowers. Ray flowers are found around the margins, and disc flowers in the center.
Pick a couple of these tiny flowers and examine under a dissecting microscope
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Kingdom Plantae Part 3
Structure and Growth
1. Obtain a softened bean seed and answer the questions below. Refer to page 131 of the
Photographic Atlas.
a. Remove the testa. From what part of the flower is this seed coat derived? What is its
ploidy?
b. You should note two large cotyledons derived from endosperm. Remove one cotyledon
to make the embryo visible. What is the ploidy of the cotyledon?
c. Is this a moncot or eudicot?
d. What is the difference between endosperm and a cotyledon?
e. Observe the bean seed with a dissecting microscope and label on the figure below:
embryo, cotyledon, plumule/epicotyl, hypocotyl, and radicle.
f. Is endosperm present? Explain.
g. Is the cotyledon part of the embryo?
h. What is the ploidy of the embryo and testa? Are they genetically identical? Explain.
2. Observe a prepared slide of a Capsella seed. Refer to page 129 in the Photographic Atlas. Make
a drawing and label the following structures: fruit, seed coat, epicotyl/plumule, hypocotyl
cotyledons, endosperm, and radicle. What is the ploidy of each of these structures?
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In addition, here are some photographs to help your studying.
3. Observe a prepared slide of a corn seed and diagram below. Refer to page 128, figure 6.273 in
the Photographic Atlas. Make a drawing and label the following structures: embryo, pericarp
(seed coat), cotyledon, coleoptile, scutellum, coleorhiza, radicle, endosperm.
a. Is this a monocot or eudicot?
b. In your drawing, note the ploidy of each of these structures.
4. Observe the models of sprouting corn and bean plants. Be able to identify the structures listed in
Question 14e (bean) and 16 (corn).
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5. Observe a live eudicot plant or a projected image. Make a simple diagram below and label the
following structures: node, leaf, petiole, rachis, blade, stem, root, apical bud, and axillary bud.
6. Obtain a slide of a Ranunculus or other eudicot root. Also look at eudicot root models in the
room. Refer to page 109 in the Photographic Atlas. Identify and label the following
structures/tissues on the figures below: Epidermis, parenchyma (note starch grains inside), stele,
endodermis, pericycle, xylem, phloem, vascular cambium, cortex.
Did you observe any chloroplasts in the eudicot root? How are root cells nourished
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7. Obtain a slide of a Zea mays (corn) or other monocot root. Refer to page 107 in the Photographic
Atlas. Identify the following parts of a monocot root and label on the figures below: epidermis,
parenchyma, endodermis, xylem, phloem, cortex, vascular cylinder, and pith.
a. Did you observe any chloroplasts in the monocot root? How are root cells nourished?
b. How are the monocot and eudicot root different from one another?
8. Obtain a Ranunculus or other eudicot stem slide, and look at models of eudicot stems in the
classroom. Refer to page 111 in the Photographic Atlas. Identify the following structures/tissues
and label them on the figures below: epidermis, cortex, pith, vascular bundles, xylem, vascular
cambium, phloem, and sclerenchyma (bundle cap fibers).
Describe how the vascular bundles are arranged in the eudicot stem.
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9. Obtain a Zea mays or other monocot stem slide, and look at the model monocot stem models in
the classroom. Refer to page 111 in the Photographic Atlas. Identify the following
structures/tissues and label on the figures below: epidermis, parenchyma, vascular bundles,
sclerenchyma (bundle fibers), xylem, phloem.
a. Describe how the vascular bundles are arranged in a monocot stem.
b. How do monocot and eudicot stems differ from one another?
c. How do roots structurally differ from stems? How would you determine whether an
underground plant structure is a root or a rhizome (underground stem)?
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10. Obtain a slide of a woody stem (Tilia) and also look at models of woody stems as well as actual
tree sections. Refer to page 112 in the Photographic Atlas. Identify the following
structures/tisssues and label on the figures below: periderm, cork cambium, xylem, phloem,
vascular cambium, secondary xylem, springwood, summerwood, annual rings.
a. Why are annual rings composed of light and dark subrings?
b. What substance is responsible for the hardness and other qualities that we normally
associate with wood?
c. What is the functional difference between heartwood and sapwood?
d. Is the xylem of a tree living or dead?
e. Is the phloem of a tree living or dead?
f. What is primary growth and what meristem is responsible for it?
g. What is secondary growth and what meristems are responsible for it?
h. Do monocots exhibit secondary growth? Explain.
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11. Using what you have learned today and during the previous lab, compare monocot and eudicot
traits for the characteristics below.
Monocot
Flower parts (#)
Root
Stem
Leaf venation
Seed (embryo)
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Eudicot
Kingdom Metazoa Part 1
1) Observe the slide labeled Starfish Embryonic Development. Refer to page 23 in the Photographic
Atlas and label the following on the figures below: unfertilized ovum, morula, blastula, early
gastrula, late gastrula, blastocoel, blastopore.
2) Observe the Poriferan specimens in the laboratory. Refer to page 151 in the Photographic Atlas.
a) Know the characteristics of each sponge class (determined by the spicules).
b) Determine whether they are asconoid, syconoid, or leuconoid body form.
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3) Obtain prepared slides of longitudinal (ls) and cross (cs) sections of the Poriferans Scypha or
Grantia . Refer to page 152 in the Photographic Atlas.
a) Label the following on the figures below: spicules, choanocytes, spongeocoel, radial canals,
mesohyl (mesoglea).
b) Is Grantia/Scypha asconoid, syconoid, leuconoid?
c) Describe the flow of water through a sponge.
d) How do they feed?
e) Why are choanocytes evolutionarily important?
f) Classify to class (look for spicules in the figures above).
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4) Observe a prepared slide of Scypha with amphiblastulas. Identify the following on the figure below:
spongocoel, radial canal, amphiblastulas.
5) Describe the role of the amphiblastulas in their life cycle.
6) Observe a prepared slide of spicules (from Scypha/Grantia). Refer to page 152 in the Photographic
Atlas. Below the figure indicate the class of the sponge from which they came and the composition
of the spicules.
Spicule composition:
Class:
7) Observe a prepared slide of spongin fibers. What class does this sponge belong to? (Hint: The
spicules have been dissolved with acid; what does that tell you about their chemical composition?)
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8) Observe all specimens of Porifera available. Be able to describe them as asconoid, syconoid, or
leuconoid forms.
9) Observe prepared slides labeled Hydra wm (whole mount) and living specimens of Hydra. Refer to
pages 154-155 in the Photographic Atlas. Make a drawing and identify the following structures:
gastrovascular cavity, hypostome, mouth, bud, epidermis, gastrodermis, mesoglea, tentacle.
In addition, here is a photograph to help your studying.
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a) Classify to class.
b) What type of symmetry do you observe?
c) Is budding sexual or asexual reproduction?
d) Is the gastrovascular cavity an open or closed system?
e) Label on the figure above where one would find cnidocytes.
10) Observe prepared slides of Obelia. Refer to page 155-156 in the Photographic Atlas.
a) Label the following structures on the figure below: hydranth (feeding polyp), gonangium
(reproductive polyp), perisarc, medusa bud, coenosarc, gastrovascular cavity (GVC).
b) What is the role of the medusae in the Obelia lifecycle?
c) Where does fertilization occur?
d) Make a simple diagram of the Obelia lifecycle.
e) Classify to class.
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11) Observe specimens of “man-o-war” Hydrozoans (genus Physalia). Refer to page 156 in the
Photographic Atlas.
a) Why are these not classified as jellyfish?
b) Identify the pnematophore.
12) Observe members of the Scyphozoa. Refer to page 157 in the Photographic Atlas.
a) Are adult scyphozoans medusae or polyps?
b) Label the following structures (Refer to page 157 in the Photographic Atlas) on the figure below:
exumbrella, subumbrella, mouth, radial canals, ring canal, gonads, tentacles. (You will not use
all label lines.)
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c) Where are cnidocytes found on a jellyfish?
d) Classify to class.
e) Look at the slides of the Aurelia lifecycle (planula, scyphistoma, ephyra, and strobila)
Be able to describe how these fit into the Scyphozoan lifecycle.
13) Observe members of the Anthozoa (living and preserved).
a) How is a coral different from an anemone?
b) What is the hard structure associated with corals composed of?
c) What type of symmetry do you observe?
d) Many corals and anemones form symbiotic relationships with dinoflagellates or other algae.
What is the general name for these symbionts?
e) Classify to class.
14) Observe and be able to identify Ctenophores. Refer to page 153 in the Photographic Atlas.
a) How are Ctenophores different from Cnidarians?
b) How do Ctenophores feed?
c) What type of symmetry do you observe?
d) Classify to phylum.
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Kingdom Metazoa Part 2
1) Observe living specimens and prepared slides (whole mount and x.s. (cross section)) of Planaria
(Dugesia or Planaria). Refer to pages 160-161 in the Photographic Atals.
a) Label the following on the figure below of a whole mount: eyespots, auricles, gastrovascular
cavity (GVC), proboscis/pharynx.
b) Label the following on the figure below: mesenchyme, gastrovascular cavity (GVC), pharyngeal
cavity, proboscis/pharynx. (Disregard the letters and arrows on the figure.)
c) Classify to class.
d) Are they free living or parasitic?
e) What is their habitat?
f) How do they locomote?
g) Do they have eyes? Explain.
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h) What type of symmetry do you observe?
i) Do they demonstrate cephalization? Explain.
j) Note the proboscis (pharynx) --what is its function?
k) Note the highly branched gastrovascular tract --is it an open or closed gut?
l) Is the Planaria coelomic, pseudocoelomic, or acoelomic?
2) Observe prepared slides of whole mount preparations of Opisthorchis (Clonorchis) sinensis. Refer
to page 162-163 in the Photographic Atlas. Make a drawing and label the following structures: Oral
sucker, ventral sucker, uterus, ovary, testes, yolk glands, GVC.
In addition, here is a photograph to help your studying
a) Classify to class.
b) What are the definitive and intermediate hosts?
c) What does it mean to say a worm (or any animal for that matter) is gravid?
3) Observe prepared slides of cercariae larva. Refer to page 163-164 of Photographic Atlas.
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a) How are they different from adult flukes? (Think about their habitat.)
b) What is their role in the worm’s life cycle?
4) Observe a prepared slide of Schistosoma mansoni (in copuli), and Schistosoma mansoni eggs.
Label the following on the figure below: male, female, oral sucker, ventral sucker, uterus. The
Photographic Atlas does not cover this organism, use the web if necessary
a) Where do these adult worms live?
b) Classify to class.
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c) Try to find Schistosoma eggs on a prepared slide if available. These eggs are pictured below and
are diagnostic for the parasite—you are looking at a slide of a fecal smear.
d) How would you determine whether an individual is infected with this worm?
e) In what part of the world is this worm most prevalent? Why there?
f) What stage of a typical trematode lifecycle is missing in Schistosoma?
5) Observe prepared slides of Taenia. Observe the scolex, an immature proglottid, a mature proglottid,
and a gravid proglottid. Refer to page 164-165 in the Photographic Atlas. Label the following on the
figures below: rostellum, suckers, scolex, testes, ovary, yolk gland, genital pore, uterus, gravid
proglottid, immature proglottid, mature proglottid.
a) What is the function of the scolex?
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b) What is the function of each proglottid?
c) Is this considered a segmented worm? Explain.
d) Do these organisms have an intestine or GVC? How do these worms feed?
6) Observe a prepared slide of Dipylidium caninum (if available) and be prepared to identify the scolex
on the lab exam.
a) What are the normal definitive and intermediate hosts of this worm?
b) How do humans get this parasite?
7) Observe an Ascaris worm. Refer to pages 176-177 in the Photographic Atlas.
a) Is this a segmented worm? Explain.
b) Classify to phylum.
c) Where can these worms normally found as adults?
d) Compare male and female worms and be able to identify sex.
e) Each pair of students will dissect an Ascaris worm. If you dissect a male, be sure to examine a
female and vice versa. Identify the following structures and their functions: Intestine, vagina,
uterus (Y-shaped), oviduct, seminal vesicle, ductus deferens. There are useful models in the
classroom to help you identify structures.
f) Is the intestine open or closed?
8) Observe a prepared slide of an Ascaris in cross section (male and female). Refer to page 177 in the
Photographic Atlas.
a) What is the cross sectional shape?
b) Is this worm acoelomic, pseudocoelomic, or coelomic?
c) Make drawings of both male and female cross sections and identify the following structures:
pseudocoelom, muscle tissue, intestine, testes, uteri, ova if observed.
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9) Observe a prepared slide of Enterobius vermicularis (wm).
a) Classify to Phylum.
b) What type of symmetry do you observe?
c) Name the definitive and intermediate hosts.
10) Observe a prepared slide of Trichinella spiralis section in muscle. Refer to page 178 of the
Photographic Atlas. Label the following in the figure below: Trichinella larva, cyst, skeletal muscle
tissue.
a) Name the normal host for these worms. How do humans get it?
b) Classify to phylum.
11) Observe live specimens of vinegar eels, if available, and classify to Phylum.
12) Observe a prepared slide of a hookworm (Ancylostoma or Necator).
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a) Classify to phylum.
b) What are the definitive and intermediate hosts.
c) Where in the US is this likely to be endemic?
13) Observe prepared slides of Rotifers (Phylum Syndermata) and be able to identify on the laboratory
exam. Refer to page 178 of the Photographic Atlas. Classify to phylum.
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Kingdom Metazoa Part 3
1) Observe a Trilobite and classify to class.
a) Are trilobites extant?
b) When did they dominate the earth?
c) Why are they considered Arthropods?
2) Observe a Horseshoe crab
a) Classify to class.
b) Refer to page 181 in the Photogrpahic Atlas. Identify the following structures on a preserved
specimen and label on the figures below: chelicerae, pedipalps, walking legs, book gills,
carapace, compound eye, abdomen opisthosoma, prosoma, telson.
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3) Observe a preserved specimen of a garden spider.
a) Classify to class.
b) Observe a prepared specimen. Refer to page 182 in the Photographic Atlas and identify the
following structures on the figure below: walking legs, cephalothorax, abdomen, chelicerae,
pedipalps, eyes, book lung, silk gland, ovary, intestine, heart, gonopore.
c) How many pairs of walking legs?
d) What appendage holds the “fangs” of a spider?
e) What is the name of the appendages posterior to those named above?
4) Observe a slide of Dermacentor, the wood tick (dissecting scope may be better) and classify to class.
5) Observe a preserved scorpion. Refer to page 183 in the Photographic Atlas.
a) Classify to class.
b) Identify the following on the specimen and label on the diagram below: cephalothorax,
pedipalps, abdomen, walking legs
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6) Observe the specimens of subphylum Crustacea available. Some are specifically mentioned below
but there may be others.
7) Observe specimens of barnacles and classify to class (Note there are two types of barnacles available
for observation, acorn barnacles and gooseneck barnacles).
8) Obtain a preserved crayfish Refer to pages 184-186 in the Photographic Atlas.
a) Classify to class.
b) Identify the following external features: pleopods, copulatory swimmerets (male), cheliped,
antennae, antennule, cephalothorax, carapace, rostrum, eye, abdomen, tergum, telson, uropod,
sperm ducts (male), mandible, maxillipeds.
9) Your instructor will describe how to dissect the preserved crayfish. Work in pairs, and be sure to
work with another pair of students who have a crayfish of the opposite sex. Observe the following
structures and know functions: gills, green gland (antenna gland), cardiac stomach, pyloric stomach,
mandibular muscle, heart, aorta, digestive gland, testes (if visible), ovaries (if visible)
10) Observe and be able to identify a Copepod and classify to class.
11) Observe and be able to identify a nauplius larva. All members of what Arthropod subphylum exhibit
this larval stage?
12) Observe a preserved specimen of a grasshopper. Refer to page 191-192 in the Photographic Atlas.
Identify the following external structures and label on the figure below: antenna, head, thorax,
abdomen, tergum, spiracles, compound eye, femur.
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13) Observe millipedes classify to class.
14) Observe centipedes and classify to class.
15) Obtain a preserved earthworm and answer the following questions. Refer to pages 174-175 in the
Photographic Atlas.
a) Classify to class and subclass.
b) Are these worms considered segmented?
c) Use a dissecting scope to observe the setae found on each segment--what is their function. How
do the setae of the Oligochaetes compare to those of the Polychaetes?
d) Note the enlarged clitellum. Is it closer to the anterior or posterior end of the worm? What is its
function?
e) Dissect the earthworm. Identify the following structures and their functions: clitellum, pharynx,
crop, gizzard, intestine, aortic arches (hearts), dorsal blood vessel, septa, seminal vesicles
(segments 9 through 14), seminal receptacles (segments 9 and 10), metanephridia, ovary
(segment 13—lucky to find). You may need to use a dissecting scope to see the metanephridia.
f) Observe a prepared slide an earthworm x.s. (Lumbricoides ) and identify the following
structures: intestine, intestinal lumen, typhlosole, coelom, muscles, epidermis. Refer to page 175
of the Photographic Atlas.
16) Observe a preserved specimen of a polychate worm (Neanthes or Nereis). Refer to page 173 of the
Photographic Atlas.
a) Classify to class.
b) Note the much larger setae, and parapodia--what is the function of the parapodia?
c) Do you see evidence that these worms are typically predators in marine sediments?
17) Look at a preserved leech.
a) Classify to class and subclass.
b) Do you see external evidence of segmentation?
c) Note the posterior sucker--what is its function?
d) What is their ecological role?
e) What is the function of hirudin in leeches?
18) Observe specimens of Bryozoa and classify to phylum.
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19) Observe specimens of Brachiopoda and classify to phylum.
20) Observe snail shells and preserved specimens of snails and slugs.
a) Classify snails to class.
b) Observe and be able to identify a prepared slide of a snail radula--what is its function?
c) How are snails different from slugs?
21) Observe specimens of clams and other bivalve mollusks.
a) Classify clams to class.
b) How do the bivalves feed?
c) Observe and be able to identify glochidia larva. These are larval clams that attach to fish gills
during development. What is the adaptive value of this type of larval form?
22) Observe preserved specimens of Chitons.
a) How many calcareous plates are present?
b) Classify to class
23) Observe specimens of Scaphopoda
a) Classify to class.
b) Are the shells open at one end or both?
c) Where does this animal live in nature?
24) Observe specimens of octopus, squid, cuttlefish, and/or nautilus.
a) Classify to class.
b) What morphological evidence do you see of a well-developed nervous system?
25) Obtain a preserved specimen of a sea star. Refer to pages 195-196 in the Photographic Atlas.
Identify the following external structures and functions: ossicles (spines), madreporite, tube feet,
ambulacral groove, oral surface, aboral surface.
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26) Your instructor will tell you how to dissect the sea star. Identify the following structures and
functions: coelom, gonad, pyloric caecum (digestive glands), stone canal, stomach, ampullae,
ambulacral ridge.
27) What is the function of the water vascular system in Echinoderms?
28) Classify the following to class.
29) Echinoderms are deuterostomes. How do deuterostomes differ from protostomes?
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30) Observe prepared slides (whole mount) and preserved specimens of lancelets (Amphioxis). Refer to
pages 202-204 in the Photographic Atlas. Make a drawing and label the following structures:
myomeres, mouth, pharyngeal slits, nerve chord, notochord, espophagus.
a) Classify to subphylum.
b) Why is this animal considered a chordate?
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Kingdom Metazoa Part 4
1) Lamprey: Observe the preserved Lamprey and refer to pages 204-206 in the Photographic Atlas.
a) Notice the mouths of these vertebrates. How are their mouths adapted to how they feed?
b) Who do you think is a more efficient swimmer, the lamprey or a shark, and why?
c) How are the gill openings different from sharks or rays?
d) Classify to class.
2) Hagfish: Observe the preserved Hagfish. (This organism is not covered in the Photographic Atlas)
a) Notice the mouths of these vertebrates. Do they have jaws? How do they feed?
b) What is the hagfish’s ecological role (niche)?
c) Why are hagfish more closely related to lampreys than sharks? (They both lack a particular
structure)
d) Classify to class.
3) Shark/Ray: Observe the preserved specimens of sharks and rays. Refer to page 207 of the
Photographic Atlas.
a) Of what is the skeleton composed?
b) Do you see any cartilagenous structures similar to the bones we see in other vertebrates? Give
examples.
c) How are the gill openings different from bony fishes?
d) Note the spiracles near the eyes. What is their function?
e) This group has placoid scales, sometimes called dentricles. Run your finger over the skin
posteriorly and then anteriorly. Do you feel any difference? Explain.
f) How many chambers does the shark heart have?
g) Be able to recognize the following fins on a shark/ray: dorsal (anterior/posterior), caudal,
pectoral, pelvic, anal, claspers in males if present (copulatory organs).
h) Would you describe the tail as homocercal or heterocercal?
i) Classify to class.
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4) Examine the examples of a bony fish. Refer to page 208 of the Photographic Atlas.
a) Classify to class.
b) How is the gill opening different from the Petromyzontida and Chondrichthyes?
c) Describe how the scales are different from a shark.
d) How many chambers does the heart have?
e) Be able to recognize the following fins: dorsal (anterior/posterior), caudal, pectoral, pelvic, and
anal.
f) Is the tail homocercal or heterocercal?
5) Ratfish/Chimera: Examine the preserved ratfish specimen. These are not covered in the
Photographic Atlas; use the web if necessary.
a) Classify to class.
b) What is a chimera (use a dictionary)? Why is this fish called a chimera?
6) Frog/Toad: Examine the frog skeleton. Refer to page 231 in the Photographic Atlas.
a) Label the following on the figure below: mandible (dentary), pelvic bone (ischium and pubis),
vertebrae, scapula, humerus, radioulna, carpals, metacarpals, phalanges, femur, tibiofibula,
tarsals, metatarsals, phalanges.
b) How many digits on the forelimb and hindlimbs? How might this be adaptive?
c) How many chambers does the heart have?
d) Classify to order (go by the lecture notes).
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7) Salamander
a) Classify to order (go by the lecture notes).
8) Caecilian
a) Classify to order (go by the lecture notes).
b) If you were free to examine the specimen closely, what characteristics would distinguish it from
an earthworm? What characteristics would distinguish it from a snake (assume you would also
be able to observe living specimens)?
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Kingdom Metazoa Part 5
1) Caiman
a) Is the animal homodontic or heterodontic?
b) How many digits in the forelimbs and hindlimbs?
c) Label the following on the figure below: mandible, cervical vertebrae, thoracic vertebrae, lumbar
vertebrae, sacral vertebrae, caudal vertebrae, scapula, humerus, radius, ulna, carpals,
metacarpals, phalanges, femur, tibia, fibula, tarsals, metatarsals, phalanges, costa(e), sternum.
d) Classify to order.
e) How many chambers in the crocodilian heart?
2) Lizard
a) Homodontic or heterodontic?
b) Do most lizards have eyelids?
c) Classify to order.
d) Describe the heart (i.e. how many chambers).
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3) Snake
a) Do snakes have eyelids?
b) From what group of reptiles did snakes evolve—i.e. who is their closest relative?
c) Identify the following on the snake skeleton: mandibles, vertebrae, costae.
d) Classify to order.
4) Turtle: Refer to page 240 in the Photographic Atlas
a) Label the following on a turtle skeleton: carapace, vertebrae, costae, scapula, clavicle (acromion
process), humerus, carpals, metacarpals, phalnges, pelvic bones, femur, tarsals, metatarsals,
phalanges.
b) Also be able to identify the plastron and scutes.
c) Of what is the carapace composed?
5) Hawk
a) What is the hawk’s ecological role and how do you know by looking at the mount or a live
animal?
b) What features suggest that birds have a reptilian ancestry?
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c) Classify to order.
6) Owl
a) What is the owl’s ecological role and how do you know?
b) How is an owl’s ecological niche different from a hawk’s and how are they physically adapted to
this difference?
c) Why do owl feathers form a dish around the face?
d) Classify to order.
7) Perching birds.
a) What morphological specialization do perching birds have for perching?
b) Do perching birds appear to fill the same ecological niches as an owl or hawk—explain?
c) Classify to order.
8) Pigeon/chicken: Refer to page 244 in the Photographic Atlas. Label the following on the skeleton
below: mandible; cervical, thoracic, lumbar, sacral, caudal vertebrae; pelvic bones, humerus, radius,
ulna, sternum, femur, clavicle, tibiotarsus, tarsiometatarsus.
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a) Note the pubis does not meet ventrally as it does in most vertebrates. What is the purpose of this
adaptation?
b) How many heart chambers in birds?
9) Opossum skeleton
a) Label the following on the diagram below: mandible, cervical vertebrae, thoracic vertebrae,
lumbar vertebrae, sacral vertebrae, caudal vertebrae, scapula, humerus, radius, ulna, carpals,
metacarpals, phalanges, femur, tibia, fibula, tarsals, metatarsals, phalanges, costa(e), sternum,
scapula, os coxae.
b) Classify to order.
c) Is the dentition homodontic or heterodontic?
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10) Beaver skull
a) Label the following on the figure: incisors, diastema, mandible.
b) How many maxillary incisors (total)?
c) For what are the cheek teeth adapted in this animal?
d) Classify to order.
11) Rabbit skull
a) Label the following: incisors, diastema, mandible
b) How many maxillary incisors do you observe?
c) For what are the cheek teeth adapted?
d) Classify to order.
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12) Dolphin skull
a) Where are the nasal openings located?
b) Note the teeth of the dolphin—are dolphins homodontic or heterodontic? For what are their
teeth adapted?
c) Classify to order.
13) Pig skull
a) List the pig dentition (how many incisors, canines, molars).
b) What kind of teeth are the tusk?
c) Based on the cheek teeth are pigs omnivores, herbivores, or carnivores?
d) Classify to order.
14) Horse leg
a) Label the bones of the horse leg (first decide if it is a foreleg or hind leg—hint: decide if the bone
at the top is a scapula or pelvic bone).
b) On what bone(s) does the horse walk?
c) Is the horse digitigrade, planitgrade or unguligrade?
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d) Classify to order.
15) Cow leg.
a) Who is a closer relative to the cow, a horse or a pig and why?
b) Identify the bones of the leg as you did for the horse leg.
c) Classify to order.
16) Dog skeleton/skull
a) Identify the following on the figure below (you do not need to label): mandible, cervical
vertebrae, thoracic vertebrae, lumbar vertebrae, sacral vertebrae, caudal vertebrae, scapula,
humerus, radius, ulna, carpals, metacarpals, phalanges, femur, tibia, fibula, tarsals, metatarsals,
phalanges, costa(e), sternum, scapula, os coxae.
b) Based on the teeth are dogs carnivores, omnivores, or herbivores?
c) Is the dog digitigrade, plantigrade or unguligrade?
d) Classify to order.
17) Cat skeleton
a) Note the distinctive carnassial molars characteristic of the Carnivora—how are they adapted to
carnivorous diet?
b) Is the cat digitigrade, plantigrade or unguligrade?
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c) How are the distal phalanges of feline feet different from canine feet (hint: look at the claws)?
d) Identify the following on the figure below (you do not need to label): mandible, cervical
vertebrae, thoracic vertebrae, lumbar vertebrae, sacral vertebrae, caudal vertebrae, scapula,
humerus, radius, ulna, carpals, metacarpals, phalanges, femur, tibia, fibula, tarsals, metatarsals,
phalanges, costa(e), sternum, scapula, os coxae.
e) Classify to order.
18) Sea lion skull
a) Homodontic or heterodontic—for what are the teeth adapted?
b) Classify to order.
19) Monkey skeleton
a) Is the cranium larger of smaller (relative to body size) than the other mammals you have
examined to this point?
b) Classify to order.
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c) Identify the following on the figure below (you do not need to label): mandible, cervical
vertebrae, thoracic vertebrae, lumbar vertebrae, sacral vertebrae, caudal vertebrae, scapula,
humerus, radius, ulna, carpals, metacarpals, phalanges, femur, tibia, fibula, tarsals, metatarsals,
phalanges, costa(e), sternum, scapula, os coxae.
20) Bat
a) How is the hand adapted to flight?
b) Label the following on the figure below: digits 1-5, clavicle, scapula, humerus, radioulna,
carpals, metacarpals, phalanges, femur, tibiofibula, calcaneous.
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c) How is the orientation of the foot different from our own? Do you suppose they walk well?
Explain.
d) Classify to order.
21) Deer and Goat
a) For what type of diet are the cheek teeth adapted?
b) Classify each to order in the space below.
Deer:
Goat:
22) Several mammal pelts are out on the tabletop. List the common name and classify to order.
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Fetal Pig Dissection
PART I - EXTERNAL ANATOMY OF THE FETAL PIG, Sus scrofa
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PART II – INITIAL CUTS
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PART III – DIGESTIVE SYSTEM
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PART IV- CIRCULATORY SYSTEM
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109
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SHEEP HEART
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PART V- EXCRETORY SYSTEM
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PART VI- REPRODUCTIVE SYSTEM
FEMALE
MALE
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PART VII- NECK, MOUTH AND THROAT
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The Mammalian Diving Response
Background: (taken from ADV PHYSIOL EDUC 27: 130–145, 2003)
When mammals dive, they must cope with the problem of being denied an external
source of oxygen. Consummate divers such as the remarkable Weddell seal may remain
submerged for up to two hours. To do so, they rely on anatomical features and physiological
responses that increase oxygen storage while reducing the use of oxygen for nonessential
activities during a dive. Blood vessels supplying nonessential organs are constricted, redirecting
blood to the oxy- gen-requiring brain and heart. Because it is supplying fewer organs with
blood, the heart can beat more slowly (a condition known as bradycardia) while maintaining
adequate blood pressure to the brain, the most metabolically sensitive organ; a further benefit of
bradycardia is that the heart requires less oxygen as well. Diving bradycardia is an easily
measured component of a group of reflexes that also include holding the breath (apnea) and
peripheral vasoconstriction. Together these reflexes constitute the “diving response.”
In comparison with diving mammals, humans are poorly adapted to life in the water. In
2002, freediving champion Mandy-Rae Cruikshank set a women’s world record for static apnea
of 6 minutes 13 seconds (the men’s record, set in 2001 by Scott Camp- bell, is 6 minutes 45
seconds), but most of us are comfortable holding our breaths for less than a minute.
The first part of this laboratory exercise is designed to demonstrate that, despite our
terrestrial nature, humans experience bradycardia when simulating a dive by holding the breath
and immersing the face in cold water. The second part of this investigatory exercise asks
students to consider the cues that stimulate the bradycardia reflex. In common parlance, this
question might be phrased “how does the body ‘know’ that it is diving?” As biologists, we
might restate this question as “what are the proximate signals that trigger diving bradycardia?”
The simulated dive holds several potential proximate cues: 1) apnea and 2) exposure of the face
to cold water, which may be further broken down into several components including cold,
wetness, and pressure. The goal of the second part of the exercise is to determine which of these
cues triggers diving bradycardia.
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T E A C H I N G
I N
T H E
L A B O R A T O R Y
FIG. 4.
Principal components of the diving response. Solid arrows indicate stimulation, dashed arrows inhibition. CNS,
central nervous system.Inputs primarily from trigeminal receptors on the upper part of the face are integrated
by the respiratory and cardiovascular centers in the medulla oblongata (in the brainstem), generating neural
signals to the lung, heart, and arterioles that include both sympathetic and parasympathetic divisions of the
autonomic nervous system. During longer dives, chemoreceptive inputs from aortic and carotid bodies help maintain
these effects. Bradycardia reduces cardiac output and therefore should reduce blood pressure, but in humans this
effect is more than compensated for by the increase in blood pressure brought about by peripheral vasoconstriction,
with the ultimate result that blood pressure increases during a dive in humans. Although arterial chemoreceptors may
respond to pH and PCO2 as well as to PO2, during diving PO2 seems to be the more important in regulating cardiovascular center outputs (14). Based on figures from Gooden (14) and Hochachka and Somero (16).
which when circulating increase blood viscosity and
tongue and upper airways) provide the first proximate cue that a dive has begun (16). Subsequent
higher heart rates that prevail when the seal is not
signals from arterial chemoreceptors reinforce and
diving
(16). Peripheral
vasoconstriction
reduces
cir- the deepen
the diving
response,
which takes several min• What
variables could
be measured
to detect
mammalian
diving
response?
culation to the muscles and other tissues while mainutes to develop fully in a diving mammal; ultimately,
taining blood flow (and hence oxygen delivery) to the
heart rate may drop to as little as 5 beats/min (8). In
brain and heart. Lowering the oxygen demand of pehumans, the response is also not immediate but de• What
control(s)
are isnecessary
in an
experiment
designed
to rapidly
test forthan
the existence
of the someripheral
tissues
during a dive
accomplished
mainly
by
velops
more
in diving mammals,
mammalian
diving
in humans?
metabolic
depression,
whichresponse
results when
tissues are
times to equally impressive levels [one human subject
cooled or become hypoxic. The reduced blood circulahad heart rates as low as 6 beats/min (16)]. A princition (hypoperfusion) caused by peripheral vasoconstricpal difference between the diving responses of hution seems to have two related functions: 1) reducing
• What factors might trigger the diving response?mans and diving mammals is that, in diving mammals,
the delivery of precious oxygen to the less needy pecardiac output (a product of heart rate and stroke
ripheral tissues, and 2) decreasing the need of periphvolume) and peripheral vasoconstriction are balanced
eral tissues for oxygen by denying them oxygen and
so that mean blood pressure does not increase during
• Describe
design
needed ato testaeach
factors.
allowing
them tothe
coolexperimental
when circulation
is restricted,
dive of
(inthese
humans,
blood pressure increases slightly
process that takes place especially quickly when the
during a dive because the effects of vasoconstriction
animal is immersed in cold water (8, 14, 25).
exceed the effects of reduced cardiac output). During
a divediving
that exceeds
the Ifaerobic
dive limit (ADL),
• Do you think the human can control the mammalian
response?
so, how?
The principal sensory components and integrative
peripheral vasoconstriction has the added advantage
pathways involved in the diving response are shown
of preventing lactic acid (lactate) produced by muscle
in Fig. 4. Trigeminal receptors on the face (and, to
cells from entering the general circulation where it
• Human
volume varies
considerably.
might have
this effect
the diving
some
extent, lung
glossopharyngeal
receptors
on theHow would
toxic effects.
Bloodresponse?
lactate typically does
Questions
for class
require the heart
to workdiscussion:
harder, particularly at the
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VOLUME 27 : 3 – ADVANCES IN PHYSIOLOGY EDUCATION – SEPTEMBER 2003
141
Procedures:
***** Participation in these experiments is not mandatory. Students who are not
comfortable with holding breath or facial immersion can still participate by measuring the
pulse of others in the group. Students who are comfortable with some treatments but not
others need only participate in the treatments they are comfortable with. This is not a
contest, there is no need to push beyond your comfort limits.
Finding the radial pulse:
• The radial pulse can be found on
the inside of the wrist, over the
radius, just below the thumb. Use
your middle and index fingers to
feel the pulse (your thumb has a
pulse of its own). If you loose it,
you may be pushing too hard. Use
light pressure only.
• Practice measuring the pulse of
others in your group. Acquiring
reliable results depends on
accurate measurement.
• During the experiments you will
be measuring the pulse in
increments of 15 seconds. Get
comfortable with timing and
reading the pulse. Coordinate with
others in your group. You may
want have one member read the
pulse and another do the timing.
118
Experiment I: A simulated dive in cold water:
Adjust a water bath to a temperature of 15±5°C by adding ice and stirring. Assign one member
of the group as the experimental subject; other members will read the pulse and record results.
Initially, measure the subject’s pulse for 15 seconds while they are calmly breathing normally.
(What is the purpose of this measurement?) Next, have the subject hold their breath and place
their entire face into the cold-water bath, remaining there for as long as they are comfortable (up
to 2 minutes). During this simulated cold-water dive, record the number of pulse beats in 15
second intervals. Record the data in the table below. Repeat for other members of the group
who are comfortable participating. Disinfecting wipes are provided to clean the water bath
between subjects.
Pulse (beats per 15 sec interval)
Subject 1 Subject 2 Subject 3 Subject 4
15 sec. while breathing
Breath-hold (min:sec)
0-0:15
0:15-0:30
0:30-0:45
0:45-1:00
1:00-1:15
1:15-1:30
1:30-1:45
1:45-2:00
Convert your pulse measurements to beats per minute by multiplying by 4. Calculate the
average bpm for each time interval. Record your averages in the class data table on the board.
Pulse (beats per minute)
Subject 1 Subject 2 Subject 3 Subject 4 AVERAGE
15 sec. while breathing
Breath-hold (min:sec)
0-0:15
0:15-0:30
0:30-0:45
0:45-1:00
1:00-1:15
1:15-1:30
1:30-1:45
1:45-2:00
119
Experiment II: Exploring the triggers of the diving response
The effect of apnea alone:
Repeat the procedure outlined above, but subjects will hold breath without facial immersion.
What potential trigger of the mammalian diving response does this experiment investigate?
Pulse (beats per 15 sec interval)
Subject 1 Subject 2 Subject 3 Subject 4
15 sec. while breathing
Breath-hold (min:sec)
0-0:15
0:15-0:30
0:30-0:45
0:45-1:00
1:00-1:15
1:15-1:30
1:30-1:45
1:45-2:00
Convert your pulse measurements to beats per minute by multiplying by 4. Calculate the
average bpm for each time interval. Record your averages in the class data table on the board.
Pulse (beats per minute)
Subject 1 Subject 2 Subject 3 Subject 4 AVERAGE
15 sec. while breathing
Breath-hold (min:sec)
0-0:15
0:15-0:30
0:30-0:45
0:45-1:00
1:00-1:15
1:15-1:30
1:30-1:45
1:45-2:00
120
Experiment III: The effect of immersion alone (no apnea):
Repeat the procedure using a snorkel during facial immersion. A disposable straw is provided
for this purpose. During this experiment, subjects may elect to wear a nose-clip to prevent
aspiration of water through the nose while breathing through the snorkel. In addition, the initial
15-second pulse measurement will need to be modified slightly to maintain a proper control.
What modification is necessary? What potential triggers (there are at least 2) of the mammalian
diving response does this experiment investigate?
Pulse (beats per 15 sec interval)
Subject 1 Subject 2 Subject 3 Subject 4
15 sec. while breathing
through snorkel before immersion
Immersion (min:sec)
0-0:15
0:15-0:30
0:30-0:45
0:45-1:00
1:00-1:15
1:15-1:30
1:30-1:45
1:45-2:00
Convert your pulse measurements to beats per minute by multiplying by 4. Calculate the
average bpm for each time interval. Record your averages in the class data table on the board.
Pulse (beats per minute)
Subject 1 Subject 2 Subject 3 Subject 4 AVERAGE
15 sec. while breathing
through snorkel before immersion
Immersion (min:sec)
0-0:15
0:15-0:30
0:30-0:45
0:45-1:00
1:00-1:15
1:15-1:30
1:30-1:45
1:45-2:00
121
Experiment IV: The effect of immersion temperature:
Repeat the procedure replacing the cold water with room-temperature water. What potential
trigger of the mammalian diving response does this experiment investigate? How is this
experiment a logical “next step” from previous experiment?
Pulse (beats per 15 sec interval)
Subject 1 Subject 2 Subject 3 Subject 4
15 sec. while breathing
Breath-hold (min:sec)
0-0:15
0:15-0:30
0:30-0:45
0:45-1:00
1:00-1:15
1:15-1:30
1:30-1:45
1:45-2:00
Convert your pulse measurements to beats per minute by multiplying by 4. Calculate the
average bpm for each time interval. Record your averages in the class data table on the board.
Pulse (beats per minute)
Subject 1 Subject 2 Subject 3 Subject 4 AVERAGE
15 sec. while breathing
Breath-hold (min:sec)
0-0:15
0:15-0:30
0:30-0:45
0:45-1:00
1:00-1:15
1:15-1:30
1:30-1:45
1:45-2:00
122
Thought questions:
1. Plot the class averages. Which variable(s) seem to be the strongest elicitors of the
mammalian diving response?
2. Are there any weaknesses to these experiments? Think about possible interactions between
the potential triggers we have considered. What additional experiments would you choose to do
to help remedy these weaknesses?
3. In a diving mammal, what would be the consequence of constricting peripheral blood vessels
without making any other circulatory adjustments? Why would this be dangerous? What
normally happens to prevent this from occurring?
4. Arrange the following species in order of how well developed you think the diving reflex
would be, from least developed to most developed, and explain your reasoning: muskrat,
tadpole, alligator, adult frog, human. Explain your reasoning.
123
5. If the function of bradycardia and the other adjustments in the body that take place during
diving is to conserve oxygen use when oxygen supplies are low, why isn’t arterial oxygen the
only proximate cue that triggers the diving response?
6. Given what you know from your results about what triggers the diving response, what do you
think would be the response of heart rate, blood flow, and metabolic rate in a human if all body
parts except the head were immersed?
7. After a harbor seal surfaces from a long dive, it experiences tachycardia (very high heart
rate). Propose a function for this tachycardia.
124