Download Biol. 100 - Contemporary Biology Name

Biol 105 – Contemporary Biology
Name _________________
Practice Questions for Second Exam – Fall 2012
1.
You carefully study populations of two very similar meadow mice, one from the
Northeast and one from Texas. You want to know whether the populations belong
to the same species or to two different species. You could most confidently
decide this if you could ...
a. show that the ranges of the two mice overlap without hydridization occurring.
b. bring the two types of mice into the laboratory and show that they can cross
and produce offspring that in turn can reproduce.
c. demonstrate that the natural ranges of the two types of mice are entirely
allopatric (separate).
d. show that there are statistically significant structural differences between the
anatomy of the two types.
e. show that the Northeastern mice live in wetter habitats than the Texan mice.
2. A phylogenetic tree of bird families would most clearly show which of the following?
a. characteristics shared by all bird families.
b. evolutionary relationships among families.
c. families that look most alike.
d. analogous structures shared by various species.
e. relative ages of living species of birds.
3. Which of the following points supports the endosymbiotic theory of eukaryotic cell
development?
a. Mitochondria have their own DNA molecules.
b. The ribosomes of mitochondria are identical to the ribosomes in other parts of
the eukaryotic cell.
c. All of the DNA in eukaryotic cells is confined to the nucleus.
d. Mitochondria are surrounded by a single membrane
e. All of the choices are correct.
4. Individual fugal filaments are called
a. mycelia
b. hyphae
c. sporangia
d. root hairs
e. mold
1
5. The tremendous increase in the diversity of animals beginning about 545 million years
ago is called the
a. critical mass.
b. Cambrian explosion.
c. Devonian diversification.
d. Permian punctuation.
e. none of the choices are correct
6. Radial symmetry is exhibited by which of the following animals?
a. flatworms and annelids
b. cnidarians and some sponges
c. roundworms and cnidarians
d. flatworms and cnidarians
e. annelids and some sponges.
7. Segmentation
a. in earthworms is homologous to the segmentation of vertebrates.
b. evolved earlier than did bilateral symmetry.
c. is a characteristic of sponges.
d. is the ability to regenerate two individual organisms from a single organism that
been cut in half.
e. increases mobility.
8. Which of the following is characteristic of vertebrates?
a. a skull and a backbone consisting of vertebrae
b. a skeleton made of bone and four legs.
c. a backbone consisting of vertebrae and a jaw.
d. a backbone consisting of betebrae and four legs
e. four legs and a jaw.
9. Which of the following is the basis for determining the causative agent of most
infectious diseases?
a. Koch’s postulates
b. Pasteur’s laws
c. trial and error
d. process of elimination
e. none of the choices are correct
10. Prokaryotes __________ eukaryotes.
a. cannot cause disease in
b. only cause disease in
c. evolved after
d. include the protistan
e. are approximately 10 times smaller than
2
11. The first membrane-enclosed systems probably contained cooperative associations
between
a. DNA and RNA.
b. DNA and ploypeptides.
c. RNA and polypeptides.
d. DNA, RNA and ploypeptides.
e. RNA, lipids, and carbohydrates.
12. Miller was the first to show that
a. the earliest forms of life were photosynthetic
b. eukaryotic life evolved from early prokaryotes.
c. the primitive atmosphere contained ammonia and methane.
d. amino acids and other organic molecules could have been generated on a
lifeless Earth.
e. the earliest forms of life had an RNA genome.
13. Which of the following is the process by which species not closely related may come
to resemble one another if they live in a similar environment?
a. coevolution
b. convergent evolution
c. similar evolution
d. parallel evolution
e. neoteny
14. A paleontologist who specializes in amphibians notices that there are very few
differences in the skull of the adult and juvenile form of a salamander. This suggests that
the salamander exhibits
a. paedomorphosis.
b. polymorphism
c. dimorphism
d. sexual dimorphism
e. convergent evolution
15. Which of the following is often called the “Age of Reptitles”?
a. late Precambrian
b. Permian
c. Paleozoic
d. Mesozoic
e. Cenozoic
3
16. Most polyploidy species arise from
a. a single diploid parent plant
b. a single triploid parent plant.
c. a single tetraploid parent plant.
d. the hybridization of two parent species
e. the hybridization of a diploid and a tetraploid parent species.
17. Which of the following prevents closely related species from interbreeding even
when their ranges overlap?
a. genetic incompatibility
b. reproductive barriers
c. taboo
d. human intervention
e. none of the choices are correct.
18. A biological species is defined as a
a. group of phenotypically indistinguishable organisms.
b. group of organisms that are phenotypically similar and that share a high
proportion of genes.
c. group of organisms that share an ancestral-descentant sequence.
d. population or group of geographically contiguous populations whose members
are phyotypically similar.
e. population or group of populations whose members have the potential to
interbreed and produce fertile offspring.
19. Long-legged cheetahs are well adapted to catching prey. The ancestor of the cheetah
is believed to have had relatively short legs. According to Darwinian views, the
evolution of long-legged cheetahs is best explained by
a. stabilizing selection.
b. the theory of use and disuse.
c. directional selection
d. the theory of acquired characteristics.
e. heterozygote advantage.
20. Which of the following assumptions was not part of Darwin’s theory of natural
selection?
a. traits are inherited as discrete particles.
b. the earth is very old
c. populations produce more offspring than their environment can support
d. organisms compete for limited resources.
e. organisms vary in heritable ways.
4
Short Answer:
CF is caused by a mutation in the gene for the protein cystic fibrosis transmembrane
conductance regulator (CFTR). This gene is required to regulate the components of sweat,
digestive juices, and mucus. Although most people without CF have two working copies
of the CFTR gene, only one is needed to prevent cystic fibrosis. CF develops when
neither gene works normally and therefore has autosomal recessive inheritance. Among
Caucasians, 98% of individuals have at least one copy the normal wild type gene.
a. If a Caucasian population is in Hardy-Weinberg equilibrium with respect to this
gene, how many CF carriers, those that have a gene but not the disease, are there
in the Bio 100 class assuming there is a total of 75 students in the class.
b. If two of the CF carriers were to marry, what percent of their children would have
the disease?
Answer Key
1. B
2. B
3. A
4. B
5. B
6. B
7. E
8. A
9. A
10. E
11. E
12. D
13. B
14. A
15. D
16. A
17. B
18. E
19. C
20. A
5