Unit 6 Review
ANSWER KEY
1. Define the following terms:
a. Big bang theory is the theory that explains the origin of the universe (13.5 bya).
b. Endosymbiotic theory is the theory that explains the origin of the organelles of
mitochondria and chloroplasts in cells by a process of phagocytosis of primitive
prokaryotes by primitive eukaryotic cells
c. Endocytosis is a process in which cells absorb molecules by engulfing them.
d. Primary endosymbiosis is the phagocytosis of a bacterium by another free-living
organism.
e. Secondary endosymbiosis is when the product of primary endosymbiosis is
engulfed.
f. Phagocytosis is when an organism (e.g. a protist) or cell engulfs another organism,
cell, or fragment.
g. Monophyletic taxa include the most recent common ancestor and its descendants.
h. Paraphyletic taxa are the result of anagenesis that includes some descendants of
a common ancestry.
i. Anagenesis is speciation without a branching or splitting of a phylogenetic tree.
j. Polyphyletic taxa have a common trait (homoplasies) but are not derived from a
common ancestor.
k. Homoplasy is the similarity in a trait for reasons other than descent from a common
ancestor, such as convergence.
l. Cladogram is a branching diagram that shows the evolutionary relationships
between organisms based on derived characters.
m. Phylogenetic tree is a branching diagram that shows the evolutionary relationships
between organisms, based on degrees of similarity.
n. Anagenesis is the speciation without a branching or splitting of a phylogenetic tree.
o. Homologous character is the similarity in a trait among two or more species,
suggesting descent from a common ancestor (e.g. bones in a whale fin and human
hand).
p. Analogous character is the similarity in a trait among two or more species but not
from a common ancestor (e.g. wings of a bat and insect).
q. Taxonomy is a science based on classification of living organisms.
r. Last Universal Common Ancestor is the most recent organism from which all
current organisms descend.
s. Cyanobacteria is a phylum of photosynthetic bacteria, the earliest producers of
oxygen on our planet.
t. Autotroph/Producer is an organism that synthesizes its own food (e.g. some
bacteria, plants) and is usually the base of the trophic system
u. Heterotroph is any organism that consumes/eats/preys on another organism (e.g.
fungi, bacteria, animals, etc.).
v. Chemotroph is a kind of autotroph/producer organism that produces energy
through the oxidation of organic and inorganic materials in their environment (in
contrast to phototrophs that use light to create energy).
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2. Match the individuals below with their accomplishments. Options may be used more
than once.
a. Carolus Linnaeus A, G, D, E
b. Charles Darwin G, F, D
c. Miller-Urey B
d. Konstantin Mereschkowski C
A. First to think of the hierarchical classification system as a genealogy
B. First to discover that Amino acids can be synthesized in the non-biotical environment
C. First to propose endosymbiotic theory
D. Unaware of the existence of genetic mutations
E. The originator of the binomial designation for species
F. An originator of the evolutionary theory
G. Used a classification scheme that did not sort homology from analogy
3. Almost all of the major animal body plans seen today appeared in the fossil record
over 500 million years ago during which period?
A. Ediacaran period
B. Permian period
C. Cretaceous period
D. Cambrian period
4. Which of the following aspects of early development differs between protostomes and
deuterostomes?
A. Pattern of early cell cleavage
B. Mechanism of coelom formation
C. Fate of the blastopore
D. All of the above
5. Angiosperms are the most successful terrestrial plants. Which of these features is
unique to angiosperms and helps account for their success?
A. Wind pollination
B. Fruits enclosing seeds
C. Ovules enclosed within seed coats
D. Sperm cells without flagella
Use the following information to answer questions 6 & 7: According to Rudyard
Kipling’s (very fictional) Just So Stories, the original whale tried to eat a man, and out of
revenge, the man stuck a grate in the whale’s throat that prevented it from eating
anything but very small fish—and that is why today’s (baleen) whales, too, only eat tiny
fish and crustaceans.
6. Which evolutionary model is this story most similar to, Darwin’s or Lamarck’s?
Lamarck’s
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7. Why?
Because it deals with the inheritance of acquired characteristics
8. Mitochondria, the organelles within eukaryotic cells, contain their own DNA. How
does the Endosymbiotic Theory help explain this?
The Endosymbiotic Theory states that eukaryotic cells derived from prokaryotic cells
that ingested other independent cells (primitive chloroplasts or mitochondria) that
became the new cell’s complex organelles. If mitochondria were once independent
cells, they would of course need their own DNA, and if they were ingested/engulfed by
other cells, they might still retain that DNA.
Use the phylogenetic tree below to answer questions 9 – 11.
9. For the tree above, does the circle represent a monophyletic, paraphyletic, or
polyphyletic group? Explain your response.
Paraphyletic group, because it does not contain all the descendants of the most recent
common ancestor.
10. For the tree above, assume the ancestor had scales, long femurs, and a small vocal
sac. Which species have smooth skin, long femurs, and a large vocal sac?
Species 3 & 6
11. For Species 4 and Species 5, which is the shared, derived trait?
Short femur
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12. Which of the following elements were not included in the Miller-Urey experiment?
A. Water
B. Methane
C. Oxygen
D. Hydrogen
E. Ammonia
13. What is the correct order in which the following organisms appeared on earth?
I. Prokaryotes II. Fungal-plant symbiosis III. Animals IV. Origin of Eukaryotes
A. I, II, III, IV
B. II, IV, I, III
C. I, IV, III, II
D. IV, I, III, II
14. Which of the following isotopes is used to date materials such as prehistoric bones
58,000 to 62,000 years before the present?
A. 14C
B. 12C
C. 40Ar
D. 207Pb
15. According to scientists hypothesizing, when did life occur on Earth?
~3.5 billion years ago
16. What are the 3 main groups of living organisms?
Archae, Bacteria, and Eukarya
17. What is the taxonomic classification of humans (kingdom, phylum, class, order,
family, genus, species)?
Animalia, Chordata, Mammalia, Primates, Hominidae, Homo sapiens
18. True or False: Large herbivores were present when terrestrial plants began
evolving. False
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19. Draw a simple diagram to represent endosymbiotic theory.
http://en.wikipedia.org/wiki/File:Endosymbiosis.PNG
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