Biology 106 Fall 2004 B

Front 1

True or False

One difference between the theories of evolution proposed by Wallace and Darwin is that Wallace believed that organisms mutate under unfavorable conditions to become better adapted

Back 1

False.

Front 2

True or False

Type 2 diabetes is an example of yesterday’s genes in today’s environment

Back 2

True

Front 3

True or False

Homologous pairs of chromosomes frequently contain different alleles

Back 3

True.

Front 4

True or False

The global hydrologic cycle supports a net flow of atmospheric water vapor from the oceans to land

Back 4

True.

Front 5

True or False

The maintenance of the cystic fibrosis allele in today’s humans may be due to increased resistance to typhoid fever in the past for people heterozygous for the normal and the disease allele.

Back 5

True.

Front 6

True or False

One reason why Old World diseases had such a devastating effect on New World populations was because of the history of large, dense populations in the Old World

Back 6

True.

Front 7

True or False

If rice gamete cells contain 12 chromosomes, then rice diploid cells will have 6 chromosomes.

Back 7

False.

Front 8

True or False

To be successful in evolutionary terms, an organism must survive longer than other members of the population

Back 8

False.

Front 9

True or False

Assimilation of atmospheric CO2 by plant photosynthesis is not a key part of the carbon cycle

Back 9

False.

Front 10

True or False

Bacteria are especially important in making phosphorus available to plants

Back 10

False.

Front 11

True or False

A typical result when a diploid cell undergoes meiosis is four haploid cells.

Back 11

True.

Front 12

True or False

The population of medium ground finches on Daphne Major shows very little variation in beak dimensions.

Back 12

False.

Front 13

True or False

A silent substitution mutation occurs when the changed DNA sequence codes for the same amino acid as the original sequence

Back 13

True.

Front 14

True or False

Plants can take in and use atmospheric nitrogen through their leaves

Back 14

False.

Front 15

True or False

The average global temperature is relatively high because carbon dioxide and other gases trap the longer wavelengths of infrared light (heat) and prevent them from radiating back into space.

Back 15

True.

Front 16

True or False

Over oceans, evaporation exceeds precipitation

Back 16

True

Front 17

True or False

During anaphase II sister chromatids separate and migrate toward opposite poles

Back 17

True

Front 18

True or False

Asexual reproduction is by far the most common form of reproduction in the animal kingdom.

Back 18

False.

Front 19

True or False

The Red Queen hypothesis of the evolution of sex maintains that sex is advantageous in a biotic environment that is constantly changing due to the presence of predators and pathogens.

Back 19

True.

Front 20

True or False

Eutrophication (excessive algal growth resulting in decreased concentrations of dissolved O2) in lakes is frequently the direct result of nitrate and phosphate runoffs from land

Back 20

True.

Front 21

The ultimate source of all genetic variation is
a. mutation
b. the environment
c. sexual recombination
d. genetic drift
e. natural selection

Back 21

a. mutation

Front 22

2. Why is crossing over important?
a. It ensures that homologous chromosomes pair
b. It prevents variation in gametes
c. It is necessary for the attachment of chromosomes to the spindle
d. It allows the exchange of genes between homologous chromosomes
e. It holds bivalents together

Back 22

d. It allows the exchange of genes between homologous chromosomes

Front 23

Natural selection primarily favors
a. genotypes
b. heterozygotes
c. phenotypes
d. homozygotes
e. mutations

Back 23

c. phenotypes

Front 24

Synapsis occurs during
a. anaphase I
b. prophase II
c. cytokinesis
d. metaphase I
e. prophase I

Back 24

e. prophase I

Front 25

The phosphorus cycle lacks a(n) _____ component.
a. mineral
b. organic
c. aquatic
d. atmospheric
e. organic

Back 25

d. atmospheric

Front 26

An explanation for seemingly dissimilar organisms, such as hummingbirds, humans, and whales, having similar skeletal structures is that
a. most evolution occurs rapidly following a mass extinction
b. dissimilar organisms might have evolved from a distant, common ancestor
c. only the best-adapted organisms can survive
d. advantageous changes can be passed along to offspring
e. they all fill similar niches and have similar selective pressures

Back 26

b. dissimilar organisms might have evolved from a distant, common ancestor

Front 27

The reason that insecticides introduced 30 years ago kill fewer insects now than in the past is that
a. many insects today are descendants of insects with insecticide-resistant characteristics
b. insects are deliberately adapting themselves to this man-made change in the environment
c. the original spraying has caused a permanent mutation, giving the insects genetic resistance to the spray
d. insects have learned to avoid areas that are sprayed by humans
e. insects that survive spraying develop an immunity to the insecticide

Back 27

a. many insects today are descendants of insects with insecticide-resistant characteristics

Front 28

If a hurricane hit a small island, leaving only a tiny group of lizards that then spread out over the island, this would be an example of the
a. bottleneck effect
b. gene flow
c. mutation
d. founder effect
e. nonrandom mating

Back 28

a. bottleneck effect

Front 29

Which of the following changes in the gene pool results in an adaptation to the environment?
a. genetic drift
b. gene flow
c. nonrandom mating
d. natural selection
e. mutation

Back 29

d. natural selection

Front 30

It was important that Mendel chose true-breeding varieties for his experiments because
a. true-breeding varieties are not heterozygous for the trait of interest
b. true-breeding varieties are more vigorous
c. true-breeding varieties are not homozygous for the trait of interest
d. true-breeding varieties are easier to cross-pollinate
e. true-breeding varieties are heterozygous for the trait of interest

Back 30

a. true-breeding varieties are not heterozygous for the trait of interest

Front 31

Which of the following is NOT a way that humans alter the carbon cycle
a. deforestation
b. burning of fossil fuels
c. draining of wetlands
d. cultivation of leguminous crops
e. manufacture of cement

Back 31

d. cultivation of leguminous crops

Front 32

In a cross between two heterozygotes (Aa), the next generation will be
a. in the ratio 1:3 homozygotes to heterozygotes
b. in the ratio 1:3 heterozygotes to homozygotes
c. all heterozygotes
d. all homozygotes
e. in the ratio 1:1 homozygotes to heterozygotes

Back 32

e. in the ratio 1:1 homozygotes to heterozygotes

Front 33

Which of the following is NOT a way that humans alter the nitrogen cycle
a. manufacture of fertilizers
b. cultivation of rice
c. burning of fossil fuels
d. land clearing for crops
e. manufacture of chlorofluorocarbons

Back 33

e. manufacture of chlorofluorocarbons

Front 34

During droughts on Daphne Major in the Galapagos, the medium ground finch
a. increases in population size
b. undergoes directional selection for larger beaks
c. undergoes directional selection for smaller beaks
d. feeds primarily on small, soft seeds
e. shows no relationship between parent beak size and offspring beak size

Back 34

b. undergoes directional selection for larger beaks

Front 35

One evolutionary puzzle for biologists is the evolution of sex. Sexual reproduction, when compared to asexual reproduction has several costs, including
a. the rapid production of identical copies of parental genotypes
b. fewer resources are needed to maintain and produce sex organs
c. the cost of producing males, which involves transferring only ½ of a parent’s genes to each offspring
d. the production of variable offspring in variable environments
e. a mechanism, in meiosis for the repair of DNA damage

Back 35

c. the cost of producing males, which involves transferring only ½ of a parent’s genes to each offspring

Front 36

Crossing over occurs during
a. prophase II
b. prophase I
c. metaphase I
d. cytokinesis
e. metaphase II

Back 36

b. prophase I

Front 37

Flower color in snapdragons is an example of incomplete dominance. If a red-flowered plant is crossed with a white-flowered plant, the F1 generation has pink flowers. If a pink-flowered plant is crossed with a pink-flowered plant, the progeny plants will be
a. 100% red
b. 25% red, 50% pink, and 25% white
c. 100% pink
d. 25% white and 75% red
e. 50% pink and 50% red

Back 37

b. 25% red, 50% pink, and 25% white

Front 38

Pathogens must do two things to be successful, reproduce and disperse to new hosts. A pathogen may be highly virulent if
a. it has a reliable means of transmission
b. it has a high rate of reproduction and poor transmission
c. it is transmitted directly from host to host
d. it cannot survive outside of the host’s body
e. it has a low rate of mutation

Back 38

a. it has a reliable means of transmission

Front 39

Sickle-cell disease can be inherited even if neither parent has the disease. This is because the disease
a. occurs only in polyploid individuals
b. is caused by a recessive allele
c. is caused by a dominant allele
d. requires certain environmental conditions to be expressed
e. occurs only in individuals who are already weak from other causes

Back 39

b. is caused by a recessive allele

Front 40

The parasite hypothesis of female choice states that females are choosing males that advertise their ability to resist diseases. Support for this hypothesis is seen in
a. the coloration of male guppies, which becomes more subdued in the presence of predators
b. pheasants, where male spur size, histocompatibility genes and offspring fitness are all positively correlated with each other
c. the attraction of females to the loudest or brightest colored male
d. the occurrence of cryptic female choice mechanisms, such as differential pollen tube growth in the styles of flowers
e. white-tailed deer, where antler size is positively related to the disease load of a buck

Back 40

b. pheasants, where male spur size, histocompatibility genes and offspring fitness are all positively correlated with each other

Front 41

homologous chromosomes

Back 41

two chromosomes in a nucleus that carry genes for the same traits in the same loci

Front 42

population

Back 42

the smallest unit that can evolve

Front 43

epistasis

Back 43

one gene pair will interact to control the expression of a second gene pair

Front 44

adaptations

Back 44

Traits that enhance an individual's ability to compete for limited resources

Front 45

stabilizing selection

Back 45

selection that favors intermediates in the distribution of traits in a population

Front 46

directional selection

Back 46

selection that favors one end of the distribution of traits in a population

Front 47

diversifying selection

Back 47

selection that favors opposite ends of the distribution of traits in a population

Front 48

artificial selection

Back 48

selection by humans for desirable traits in an organism

Front 49

sexual selection

Back 49

selection for traits that increase mating success

Front 50

tetrads

Back 50

a paired set of homologous chromosomes, each composed of two sister chromatids

Front 51

chromatids

Back 51

a chromosome and its replicated copy formed prior to mitosis or meiosis

Front 52

synapsis

Back 52

the pairing of replicated homologous chromosomes during meiosis

Front 53

genotype

Back 53

the combination of alleles in an individual for a gene

Front 54

chiasmata

Back 54

Regions of chromosomes where nonsister chromatids cross over

Front 55

phenotype

Back 55

the physical and physiological traits of an organism

Front 56

alleles

Back 56

alternative forms of a gene

Front 57

pleiotropy

Back 57

A single genetic locus that controls more than one trait

Front 58

gene pool

Back 58

all the individual alleles in a population for a given locus

Front 59

polyploidy

Back 59

a multiplying of the diploid number of chromosomes

Front 60

anisogamy

Back 60

the occurrence of two different sized gametes in the sexes