Name:
KEY
Last
First
ID#___________________________
Lab. Date and Time____________________
Lab. TA____________________
Biological Sciences 1B – Dr. Herrlinger
Summer Sessions I 1998
Final Exam
August 7, 1998
Please Read the Instructions First
Check your pages. There are 13 pages in this exam.
You are responsible for making sure that you have all the pages.
This examination is worth 130 points.
Write your name, ID#, and Lab. Section on your scantron.
Multiple Choice Questions
1. Indicate your answers on the scantron sheet using a number 2 or test scoring pencil. Press
heavily, don’t stray out of the margins, and completely erase any changed answers.
2. If you think that a multiple choice question is ambiguous or confusing, use the “gripe sheet” at
the end of the examination to explain the problem.
3. There are 45 multiple choice questions worth 2 points each.
Fill-in Questions
1. Use pen only (no grade corrections for pencil or white–out).
2. Write only one answer per question. You can elaborate on an answer, but you will not be
given any credit if you write two different answers to the question.
3. Spelling rules: ½ credit for 2–3 letters wrong or transposed. No points will be given if the
misspelling alters the meaning of the word.
4. There are 12 fill–in questions worth 40 points in total.
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Choose the one best answer:
1. An organism is considered colonial if
a.
b.
c.
d.
e.
it undergoes asexual reproduction
the body tissue has differentiated into more than two layers
the polyps touch each other
there are two or more adult body morphs in different habitats
there is a gastrovascular connection among individuals
2. When somatic development is unchanged and sexual maturity occurs early in a large larval
form, this is an example of
a.
b.
c.
d.
e.
neoteny
hemimetabolous
progenesis
teloblastic growth
b and c
3. Which of the following is NOT true about hemimetabolous and holometabolous
metamorphosis?
a.
b.
c.
d.
e.
Crickets undergo hemimetabolous metamorphosis.
Holometabolous metamorphosis contains a pupal stage.
During holometabolous metamorphosis, the larva and adult consume different foods.
The young in hemimetabolous metamorphosis look like miniature adults.
All of the above are true statements.
4. A hydrostatic skeleton would be characteristic of which of the following taxa?
a.
b.
c.
d.
e.
Polychaeta
Porifera
Uniramia
Vertebrata
none of the above
5. Onychophorans
a.
b.
c.
d.
e.
are most closely related to oligochaetes
are unknown from the fossil record
have multiple pairs of gills
lay terrestrial eggs
possess characteristics of both annelids and arthropods
6. Asteroid tube feet can be used for all of the following EXCEPT:
a.
b.
c.
d.
e.
attachment
locomotion
prey capture
respiration
reproduction
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7. What type of skeleton best describes Class Ophiuroidea?
a.
b.
c.
d.
e.
acoelomic
calcareous endoskeleton
exoskeleton
hydrostatic
none of the above
8. Aristotle’s lantern is
a.
b.
c.
d.
e.
a developmental structure found in tunicates
a feeding structure in echinoids
a paper bag with a lighted candle used to illuminate walkways during Halloween
a photoreceptor at the tips of arms in asteroids
used for locomotion
9. A zooid of a colonial (but not compound) tunicate has
a.
b.
c.
d.
e.
an individual incurrent siphon and a common excurrent siphon
an individual incurrent siphon and an individual excurrent siphon
a common incurrent siphon and an individual excurrent siphon
common incurrent and excurrent siphons
none of these describe a colonial tunicate
10. Tunicates, salps, and larvaceans belong to
a.
b.
c.
d.
e.
Kingdom Protozoa
Phylum Echinodermata
Subphylum Cephalochordata
Subphylum Urochordata
Subphylum Vertebrata
11. Vertebrate jaws most likely evolved from which structure?
a.
b.
c.
d.
e.
an expansion of the nasal passages
the first gill arch
mesoderm
the pharyngeal basket
scientists have no idea which structure the jaws evolved from
12. The amniotic egg permits
a.
b.
c.
d.
e.
complete development of the young in absence of parental care
internal fertilization
production of more young
reproduction independent of an aquatic environment
all of the above
3
13. Which of the following contains the most closely related animal to you?
a.
b.
c.
d.
e.
Cephalochordata
Cephalopoda
Crinoidea
Holothuroidea
Urochordata
14. Salmon hatch from eggs in freshwater. Later in life they migrate to the sea where they grow
to maturity. Salmon return to freshwater to reproduce. How do salmon physiologically
adjust to seawater when they first migrate from freshwater?
a.
b.
c.
d.
e.
They do not need to physiologically adjust since salmon are isosmotic with seawater.
They drink water and accumulate ions using their gills.
They drink water, produce little urine, and excrete ions across the gills.
They produce a lot of dilute urine and accumulate ions using the gills
They produce a lot of dilute urine and excrete ions across the gills
15. There are numerous examples of mating systems where the female provides most or all of the
parental care and the male provides little or no parental care. In this type of mating system,
males often compete among themselves for females. Which animals show the opposite
pattern?
a.
b.
c.
d.
e.
elephant seals
ostriches
poison arrow frogs
zebras
none of the above
16. The origin of vertebrates is suggested to have come from an early chordate where the tadpole
larva never underwent metamorphosis, yet the body increased in size. This is an example of:
a.
b.
c.
d.
e.
adaptive radiation
anagenesis
cladogenesis
paedomorphosis
stasis
17. All of the following structures increase the surface area to volume ratio EXCEPT:
a.
b.
c.
d.
e.
clitellum
folded internal membranes of protozoans
leuconoid body design
septa
typhlosole
18. The classes Hydrozoa and Asteroidea are similar in that
a.
b.
c.
d.
e.
both taxa are completely marine
both taxa are triploblastic
most members are carnivorous
most members are sequential hermaphrodites
most members have special defensive cells with venom
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19. In a population of pigs, suppose a gene determines susceptibility to stress. S confers high
susceptibility to stress and is dominant to s which is unaffected by stress. If the population is
in Hardy–Weinberg equilibrium and f(S) = 0.85 and f(s) = 0.15, what is the frequency of pigs
highly susceptible to stress?
a.
b.
c.
d.
e.
(0.85)(0.85)
(0.15)(0.15)
2(0.85)(0.15)
sum choice a and choice b
sum choice a and choice c
20. A paraphyletic group includes
a. all descendants but not the most recent common ancestor
b. the most recent common ancestor and all descendents
c. the most recent common ancestor but not all descendents
21. In __________, the __________ becomes the mouth.
a.
b.
c.
d.
e.
deuterostomes; archenteron
deuterostomes; blastocoel
deuterostomes; blastopore
protostomes; archenteron
protostomes; blastopore
22. One species of ground squirrel lives in a dry habitat and primarily eats insects. Another
species of ground squirrel lives in a moist forest and eats mainly nuts. These two species are
most likely maintained by
a.
b.
c.
d.
e.
frequency dependent selection
hybrid inviability
norms of reaction
spatial isolation
temporal isolation
23. Which of the following does NOT characterize the Class Insecta?
a.
b.
c.
d.
e.
one pair of antennae
pedipalps
three tagmata
uniramous appendages
wings
24. Fused ossicles form a test in which class of echinoderms?
a.
b.
c.
d.
e.
Asteroidea
Crinoidea
Echinoidea
Holothuroidea
Ophiuroidea
5
25. Adult tunicates in the Class Ascidiacea retain which of these distinguishing chordate
characteristics?
a.
b.
c.
d.
e.
dorsal tubular nerve cord
notochord
pharyngeal gill slits
postanal tail
adults retain them all
26. Colonialism with polymorphism (division of labor) is NOT found in which of the following
taxa?
a.
b.
c.
d.
e.
Kingdom Protozoa
Phylum Arthropoda
Phylum Cnidaria
Phylum Mollusca
All of the above taxa contain examples of colonial life and division of labor.
27. The distribution of human baby birth weights discussed in class shows an example of
a.
b.
c.
d.
e.
directional selection
disruptive or diversifying selection
stabilizing selection
stasis
weak selection
28. Phyla Annelida, Arthropoda, and Mollusca are more closely related to each other than to
other phyla because all three phyla have
a.
b.
c.
d.
e.
a hydrostatic skeletons
a reduced coelom
heteronomous segmentation
protostome characteristics
the same larva
29. Taxa that exhibit adaptive radiation are
a.
b.
c.
d.
e.
Insecta and Mollusca
Insecta and Polychaeta
Mollusca and Polychaeta
all of the above
none of the above
30. Which of the following is NOT a true statement?
a. Just like flying squirrels, there is a species of gliding lizard with webbing between its
limbs.
b. The acidity of coal prevents the formation of fossils.
c. Some lizards are capable of bipedal locomotion.
d. There is a living bird that has claws on its wings as a chick.
e. There is a lungfish that secretes a paper cocoon enabling it to survive for months in a hard,
dry, hunk of sediment that used to be mud.
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31. Why don’t living coral reefs exist at deep ocean depths?
a.
b.
c.
d.
e.
corals cannot survive the cold temperatures in the deep ocean
corals cannot find mates at this depth
internal coral symbionts require light to survive
stronger competitors exclude corals at deep ocean depths
symbiotic clownfishes cannot survive the pressure at this depth
32. Which of the following is NOT characteristic of the Phylum Platyhelminthes?
a.
b.
c.
d.
e.
acoelomate
bilateral symmetry
complete gut
spiral cleavage
triploblastic
33. Lynn Margulis’s idea of how a eukaryotic protozoan originated from a prokaryote is called
the:
a.
b.
c.
d.
e.
cellular aggregation theory
colonial theory
crummy theory
serial endosymbiont theory
syncytial theory
34. On a dark night, when you wave your hand underwater in the ocean and see a streak of
bioluminescence, you are stimulating _______________ which are _______________
organisms.
a.
b.
c.
d.
e.
copepods; animal-like
dinoflagellates; plant–like
larval squid; animal–like
polychaetes; animal–like
radiolarians; plant–like
35. Which of the following is TRUE concerning hermaphrodites?
a.
b.
c.
d.
e.
simultaneous hermaphrodites are male and female at the same time
they are dioecious
they cannot reproduce sexually
they nearly always practice self–fertilization
all of the above
36. Size dimorphism is NOT a feature of which of the following groups?
a.
b.
c.
d.
e.
elephant seals
mountain sheep horns
ostriches
spiders
the elongated tooth in narwhals
7
37. Which of the following taxa is most likely to be polyphyletic?
a.
b.
c.
d.
e.
Annelida
Arthropoda
Echinodermata
Insecta
Mollusca
38. Most biological diversity has probably arisen by
a.
b.
c.
d.
e.
anagenesis
cladogenesis
extinction
stasis
sympatric speciation
39. In a population with two alleles for a particular locus, B and b, the allelic frequency of B is
0.7. What would be the frequency of heterozygotes if the population is in Hardy–Weinberg
equilibrium?
a.
b.
c.
d.
e.
0.09
0.21
0.42
0.49
0.70
40. The slits in the chordate pharynx probably first evolved as what type of structure?
a.
b.
c.
d.
e.
circulatory
digestive
filter–feeding
locomotory
sensory
41. If a marine fish were to survive in freshwater, what would it need to do?
a.
b.
c.
d.
e.
drink lots of freshwater; cells in gills release ions
drink lots of freshwater; excrete concentrated urine
excrete concentrated urine; cells in gills release ions
excrete lots of dilute urine; cells in gills pick up ions
nothing since it would be isosmotic
42. Which organism is phylogenetically closest and most likely the ancestor to the first terrestrial
tetrapod?
a.
b.
c.
d.
e.
a cephalochordate
a coelacanth
a hagfish
a lamprey
a tunicate
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43. Natural selection acts directly on the
a.
b.
c.
d.
e.
gene pool
genotype
phenotype
population
species
44. Evidence for the evolution of vertebrate jaws from gill arch supports comes from
a.
b.
c.
d.
e.
the ectodermal origin of jaws
the homology between jaw and tail musculature
the mesodermal origin of jaws
the hydrostatic skeleton used by jaws
the three–part structure of the jaws
45. The ability to make structures out of calcium is
a.
b.
c.
d.
e.
absent in echinoderms
absent in sponges
unique to molluscs
unique to multicellular animals
widespread among the phyla
Short answer:
46. What is torsion and in what taxonomic group (be specific) is it found? (2 pts.)
Torsion is the 180º twisting of the visceral mass with respect to the head–foot axis
during gastropod development. Class Gastropoda.
47. Name a class of echinoderms that has bilaterally symmetrical representatives. Explain how
symmetry has changed in the evolution of these organisms. (3 pts.)
Class Echinoidea, Holothuroidea. Early ancestors were bilateral (as seen in the larvae),
immediate ancestors exhibited pentaradial symmetry, and some recent forms are
bilaterally symmetrical again (heart urchins, sand dollars, certain sea cucumbers)
48. Explain why an analogous character is not reliable for determining phylogenetic
relationships. (2 pts.)
Unrelated organisms can look similar and possess similar structures that were derived
by convergent evolution. Many organisms have solved similar problems with similar
solutions.
49. A female Anopheles mosquito has been reared from an egg under sterile conditions in a
laboratory. Once it is released into the wild in Africa, what is the minimum number of bites
on humans required to transmit the malarial disease? Why? (2 pts.)
Two. The mosquito will pick up the parasite on its first blood meal and transmit it on
the next bite.
9
50. Are the protozoans considered a monophyletic group? What one diagnostic characteristic is
used to classify them? (2 pts.)
No. The method of locomotion is used to classify protozoans.
51. If you removed one viable snake egg from its clutch and kept it underwater in a nearby pond
at the same water temperature as the other eggs developing in air, would the underwater egg
eventually hatch? Why or why not? (2 pts.)
No. The shell is porous and there would be insufficient oxygen exchange.
52. Coelom formation is schizocoelous in chordates and enterocoelous in echinoderms. Yet it is
generally accepted that chordates and echinoderms are members of the same evolutionary
line. Why? List the similarities. (3 pts.)
They are both deuterostomes and have:
1. radial cleavage
2. indeterminate cleavage
3. blastopore becomes the anus
53. From a tunicate tadpole larva, how might a large, free–swimming, filter–feeding chordate
have evolved? (3 pts)
A tadpole larval stage increased in size by neoteny, was able to swim and filter–feed,
and delayed its metamorphosis to the sessile stage. Eventually metamorphosis was
eliminated.
54. At Hardy–Weinberg equilibrium, suppose that a certain disease caused by a recessive allele
occurs in 4% of the population. What is the frequency of heterozygous “carriers” of the
disease? Show your work. (3 pts.)
Assume R is the dominant allele and r is the recessive allele.
rr = 4% of the population so f(rr)=0.04; allele frequency of r is
Therefore f(R)= 1 – r = 1 – 0.2 = 0.8
heterozygotes are Rr and f(Rr) = 2pq = 2 (0.8) (0.2) = 0.32
10
0.04 = 0.2
Matching:
55. Match a single letter from the right hand column with each of the following: (10 pts.)
Be sure to write legibly!
black widow spider
A
A. Arachnida
blue crab
E
B. Asteroidea
blue–ringed octopus
D
C. Bivalvia
bristle worm
J
D. Cephalopoda
chiton
K
E. Crustacea
crown–of–thorns sea star
B
F. Gastropoda
dragonfly
H
G. Hirudinea
earthworm
I
H. Insecta
medicinal leech
G
I. Oligochaeta
moon jelly
L
J. Polychaeta
K. Polyplacophora
L. Scyphozoa
M. Urochordata
11
56. Which Class contains the greatest number of described species on our planet? (2 pts.)
Class Insecta
57. Select 3 of the 6 letters below. In a few sentences, describe how each of the following
features of an animal’s body plan contribute to its adaptation and subsequent evolution.
AND, name the specific phylum in which this feature first evolved. (6 pts.)
a. mesoderm
Muscles and the axial skeleton are derived from mesoderm [and this third tissue
layer increases the number of tissue–layer interactions].
Mesoderm lines the coelom (fluid–filled cavity inside the mesoderm) and forms a
packing layer around the gut.
First evolved in the Platyhelminthes
b. coelom
Provides a tube–within–a–tube arrangement that allows body flexibility, space for
visceral organs, and cushions and isolates the gut form the motion of the rest of the
body. A compartmentalized coelom acting as a hydrostatic skeleton was essential for
burrowing animals.
First evolved in Annelida (well–developed coelom), Arthropoda (reduced coelom),
Mollusca (reduced coelom) [accept any of these]
c. bony jaws
Organisms that were previously filter–feeders could now prey on large and active
forms of food not available to jawless vertebrates.
First evolved in Chordata
d. tagmatization
Allows for specialization of regions with different functions for the segments.
First evolved in Arthropoda
e. metamerism
Allows segments to be separated by septa, permitting greater complexity in structure
and function. Such morphological diversity includes modifications in locomotion.
First evolved in Platyhelminthes (cestodes), Annelida [accept either]
f. lungs
Permits aerial respiration through the nose, reduction of evaporative water loss, and
more efficient respiration for terrestrial life.
First evolved in Chordata
Enjoy the rest of your summer!
12
Name: ___________________________
Last
First
ID#________________________
Gripe Sheet
Instructions:
1. Put your name at the top of the page.
2. If you think that a question is ambiguous or confusing, indicate the question number, the
answer you gave, and the reason that you gave this answer.
Question # Answer you gave
Gripe
13