BIO 110 Exam 4

In unicorns, three alleles at a gene determine the condition of the horn. The allele for a twisted horn, HT, and the allele for a long horn, HL, are codominant; both are completely dominant to the hornless allele, h. The frequency of hornless individuals in the population is 16%, and the frequency of the allele for twisted horns is 0.1. What is the frequency of the long horn allele? a. .40 (40%) b. .10 (10%) c. .50 (50%) d. .05 (5%)

.50 (50%)

Consider a population of wildflowers in which the frequency of the red allele CR is p = 0.7. What is the frequency of the white allele (CW ) in this population? a. 0 b. 0.3 c. 0.49 d. 0.7

0.3

The frequency of the brown allele in this beetle population is

0.4

The frequency of the green allele in this beetle population is

0.6

In peas, a gene controls flower color such that R = purple and r = white. In an isolated pea patch, there are 36 purple-flowering plants and 64 white-flowering plants. Assuming Hardy-Weinberg equilibrium, what is the value of q for this population? a. 0.75 b. 0.64 c. 0.36 d. 0.80

0.80

In a Hardy-Weinberg population with two alleles, A and a, that are in equilibrium, the frequency of allele a is 0.1. What is the frequency of individuals with AA genotype? a. 0.42 b. 0.81 c. 0.20 d. 0.32 e. Genotype frequency cannot be determined from the information provided.

0.81

Big Bend National Park in Texas is mostly Chihuahuan desert, where rainfall averages about 10 inches per year. Yet, it is not uncommon when hiking in this bone-dry desert to encounter mosses and ferns. One such plant is called "flower of stone." It is not a flowering plant, nor does it produce seeds. Under arid conditions, its leaflike structures curl up. However, when it rains, it unfurls its leaves, which form a bright green rosette on the desert floor. Consequently, it is sometimes called the "resurrection plant." At first glance, it could be a fern, a true moss, or a spike moss. Upon closer inspection of the leaves of flower of stone, one can observe tiny, cone-like structures. Each cone-like structure emits spores of two different sizes. Consequently, flower of stone should be expected to possess which other characteristics? 1. a gametophyte generation that is dominant 2. lignified vascular tissues 3. filamentous rhizoids, but not true roots 4. spores that are diploid when mature

1 and 3

Big Bend National Park in Texas is mostly Chihuahuan desert, where rainfall averages about 10 inches per year. Yet, it is not uncommon when hiking in this bone-dry desert to encounter mosses and ferns. One such plant is called "flower of stone." It is not a flowering plant, nor does it produce seeds. Under arid conditions, its leaflike structures curl up. However, when it rains, it unfurls its leaves, which form a bright green rosette on the desert floor. Consequently, it is sometimes called the "resurrection plant." At first glance, it could be a fern, a true moss, or a spike moss. Upon closer inspection of the leaves of flower of stone, one can observe tiny, cone-like structures. Each cone-like structure emits spores of two different sizes. Based on this information, which of the following can be properly inferred about flower of stone? 1. It is heterosporous. 2. It is a fern. 3. The cone-like structures are sori. 4. It has separate male and female gametophytes.

1 and 4

The microsporidian, Brachiola gambiae, parasitizes the mosquito, Anopheles gambiae. Adult female mosquitoes must take blood meals in order for their eggs to develop, and it is while they take blood that they transmit malarial parasites to humans. Male mosquitoes drink flower nectar. If humans are to safely and effectively use Brachiola gambiae as a biological control to reduce human deaths from malaria, then how many of the following statements should be true? 1. Brachiola should kill the mosquitoes before the malarial parasite they carry reaches maturity. 2. The microsporidian should not be harmful to other insects. 3. Microsporidians should infect mosquito larvae, rather than mosquito adults. 4. The subsequent decline in anopheline mosquitoes should not significantly disrupt human food resources or other food webs. 5. Brachiola must be harmful to male mosquitoes, but not to female mosquitoes.

1, 2, and 4

In unicorns, three alleles at a gene determine the condition of the horn. The allele for a twisted horn, HT, and the allele for a long horn, HL, are codominant; both are completely dominant to the hornless allele, h. The frequency of hornless individuals in the population is 16%, and the frequency of the allele for twisted horns is 0.1. What frequency of individuals in the population have horns that are long and twisted? a. 25% b. 10% c. 84% d. 5%

10%

In this beetle population, the total number of alleles is

20

Big Bend National Park in Texas is mostly Chihuahuan desert, where rainfall averages about 10 inches per year. Yet, it is not uncommon when hiking in this bone-dry desert to encounter mosses and ferns. One such plant is called "flower of stone." It is not a flowering plant, nor does it produce seeds. Under arid conditions, its leaflike structures curl up. However, when it rains, it unfurls its leaves, which form a bright green rosette on the desert floor. Consequently, it is sometimes called the "resurrection plant." At first glance, it could be a fern, a true moss, or a spike moss. Which of the following characteristics is (are) possessed in common by true mosses, ferns, and spike mosses, and therefore becomes useless at helping to determine to which of these groups flower of stone belongs? 1. a sporophyte generation that is dominant 2. true leaves and roots 3. flagellated sperm 4. alternation of generations

3 and 4

Plants evolved from green algae approximately _____ million years ago. a. 3,500 b. 2,200 c. 130 d. 475 e. 400

475

Suppose 64% of a remote mountain village can taste phenylthiocarbamide (PTC) and must, therefore, have at least one copy of the dominant PTC taster allele. If this population conforms to Hardy-Weinberg equilibrium for this gene, what percentage of the population must be heterozygous for this trait? a. 16% b. 40% c. 48% d. 32%

48%

In this beetle population, the number of brown alleles is

8

You sample a population of butterflies and find that 56% are heterozygous at a particular locus. What should be the frequency of the recessive allele in this population? a. 0.09 b. 0.08 c. 0.70 d. 0.07 e. Allele frequency cannot be determined from this information.

Allele frequency cannot be determined from this information.

What do fungi and arthropods have in common? a. Both groups have cell walls. b. Both groups use chitin for support. c. The haploid state is dominant in both groups. d. Both groups are predominantly autotrophs that produce their own food.

Both groups use chitin for support.

Long necks make it easier for giraffes to reach leaves high on trees, while also making them better fighters in "neck wrestling" contests. In both cases, which kind of selection appears to have made giraffes the long-necked creatures they are today? a. Disruptive selection b. Stabilizing selection c. Directional selection

Directional selection

Black-bellied seedcrackers have either small beaks (better for eating soft seeds) or large beaks (better for hard seeds). There are no seeds of intermediate hardness; therefore, which kind of selection acts on beak size in seedcrackers? a. Disruptive selection b. Stabilizing selection c. Directional selection

Disruptive selection

Which type of selection tends to increase genetic variation? a. Disruptive selection b. Stabilizing selection c. Directional selection

Disruptive selection

Which of the following is a difference between plants and fungi? a. Fungi are heterotrophic, and plants are autotrophic. b. Fungi have cell walls. c. Plants produce spores. d. Plants have diploid and haploid phases, and fungi have only haploid stages. e. Fungi are strictly asexual, and plants undergo sexual reproduction.

Fungi are heterotrophic, and plants are autotrophic

Almost all of the members of this phylum form arbuscular mycorrhizae in a mutualistic partnership with plants. a. Chytridiomycota b. Ascomycota c. Basidiomycota d. Glomeromycota e. Zygomycota

Glomeromycota

Which of the following events occurs first in the development of a spore into a mature mushroom? a. The mycelium forms. b. Hyphae are produced by mitosis. c. A heterokaryotic mycelium forms. d. Haploid nuclei fuse to form a diploid nucleus.

Hyphae are produced by mitosis

Melanin is a pigment protein that causes cells to become dark in color. In fungi, melanin is sometimes referred to as "fungal armor" because it protects fungal cells from a wide range of stressors. Researchers in Israel's Evolution Canyon system studied the adaptive melanin response of the soil fungus Aspergillus niger to UV radiation. UV radiation causes mutations in DNA. Based on your knowledge of the Evolution Canyon system, which of the following is a likely difference between populations of A. niger found on the African slope (AS) and the European slope (ES)? a. Mean melanin concentration is significantly higher on the shady ES than on the sunny AS. b. Mean melanin concentration is significantly higher on the sunny AS than on the shady ES. c. There is no reason to expect a difference in melanin concentration between the ES and AS populations.

Mean melanin concentration is significantly higher on the sunny AS than on the shady ES.

Consider a wildflower population with the following allele and genotype frequencies. Frequency of the CR allele: p = 0.6 Frequency of the CW allele: q = 0.4 Frequency of CRCR : 50% Frequency of CRCW : 20% Frequency of CWCW : 30% Is this population in Hardy-Weinberg equilibrium? a. Yes, the genotype frequencies are what we would expect for a population in Hardy-Weinberg equilibrium. b. No, the frequency of genotype CWCW is too low. c. No, the frequency of genotype CRCR is too low. d. No, the frequency of genotype CRCW is too low.

No, the frequency of genotype CRCW is too low.

Small Aristelliger lizards have difficulty defending territories, but large lizards are more likely to be preyed upon by owls. Which kind of selection acts on the adult body size of these lizards? a. Disruptive selection b. Directional selection c. Stabilizing selection

Stabilizing selection

Women often have complications during labor while giving birth to very large babies, whereas very small babies tend to be underdeveloped. Which kind of selection is most likely at work regarding the birth weight of babies? a. Disruptive selection b. Directional selection c. Stabilizing selection

Stabilizing selection

Which of the following is true concerning flowering plants? a. The flower includes sporophyte tissue. b. The sporophyte generation consists of relatively few cells within the flower. c. The sporophyte generation is not photosynthetic. d. The gametophyte generation is what we see when looking at a large plant. e. The gametophyte generation is dominant.

The flower includes sporophyte tissue.

Fungi have an extremely high surface-to-volume ratio. What is the advantage of this characteristic to an organism that gets most of its nutrition through absorption? a. This high ratio means that fungi have a thick, fleshy structure that allows the fungi to store more of the food it absorbs. b. The lower volume prevents the cells from drying out too quickly, which can interfere with absorption. c. This high ratio creates more room inside the cells for additional organelles involved in absorption. d. The high ratio allows for more material to be acquired from the surroundings and transported through the cell membrane.

The high ratio allows for more material to be acquired from the surroundings and transported through the cell membrane.

A group of small fish live in a lake with a uniformly light-brown sandy bottom. Most of the fish are light brown, but about 10% are mottled. This fish species is often prey for large birds that live on the shore. A construction company dumps a load of gravel in the bottom of the lake, giving it a mottled appearance. Which of these statements presents the most accurate prediction of what will happen to this fish population? a. The proportion of mottled fish will increase over time. b. There is no way to predict the result. c. The ratios will not change. d. In two generations, all the fish will be mottled. e. As the mottled fish are eaten, more will be produced to fill the gap.

The proportion of mottled fish will increase over time.

In a bell-shaped curve, the x-axis (horizontal direction) of the graph represents which of the following? a. Time b. The value of a particular characteristic; characteristics of an organism can include such traits as size and color. c. The number of individuals

The value of a particular characteristic; characteristics of an organism can include such traits as size and color.

In fungi, haploid hyphae fuse to produce dikaryotic and then diploid nuclei, only to restore the haploid condition by meiosis before the growth of new hyphae. What is the significance of a transient diploid state in fungi? a. These sexual processes generate genetic variation. b. All organisms must reproduce sexually at some point in their life cycle. c. The diploid state is more advanced than the haploid state.

These sexual processes generate genetic variation.

Which of the following must exist in a population before natural selection can act upon that population? a. genetic variation among individuals b. sexual reproduction c. variation among individuals in reproductive success d. Three of the responses are correct. e. Two of the responses are correct.

Two of the responses are correct.

An adaptation is _____. a. the cause of natural selection b. a trait that gives rise to a new species c. a trait that gives an organism a reproductive advantage in the current environment d. an individual's attempt to conform to its environment e. all of the above

a trait that gives an organism a reproductive advantage in the current environment

Fungi obtain nutrients through _____. a. photosynthesis b. ingestion c. endocytosis d. chemosynthesis e. absorption

absorption

The adaptive advantage associated with the filamentous nature of fungal mycelia is primarily related to _____. a. the increased probability of contact between different mating types b. an extensive surface area well suited for invasive growth and absorptive nutrition c. the potential to inhabit almost all terrestrial habitats d. the ability to form haustoria and parasitize other organisms

an extensive surface area well suited for invasive growth and absorptive nutrition

All seed plants _____. a. are nonvascular b. exhibit a dominant gametophyte generation c. produce flowers d. are heterosporous e. produce antheridia and archegonia on the same gametophyte

are heterosporous

Green algae differ from land plants in that many green algae a. have alternation of generations. b. have cell walls containing cellulose. c. have plastids. d. are heterotrophs. e. are unicellular.

are unicellular.

Where does meiosis occur in a mushroom? a. Mycelium b. Basidia c. Spores d. Hyphae

basidia

To calculate the frequency of the brown allele, count the number of ___________ and divide by the total number of alleles in this population.

brown alleles

The living plants that are most similar to the first plants to bear gametangia are the _____. a. gymnosperms b. bryophytes c. charophyceans d. seedless vascular plants e. angiosperms

bryophytes

Seedless plants include _____. a. only lycophytes and pterophytes b. only nonvascular plants c. bryophytes, lycophytes, ferns, whisk ferns, and horsetails d. bryophytes and gymnosperms e. mosses and angiosperms

bryophytes, lycophytes, ferns, whisk ferns, and horsetails

Most fungi are _____. a. photoautotrophs b. decomposers c. herbivores d. carnivores e. chemoautotrophs

decomposers

The conspicuous part of a fern plant is a _____. a. haploid sporophyte b. haploid gametophyte c. diploid gametophyte d. diploid sporophyte e. diploid sorus

diploid sporophyte

When you look at a pine or maple tree, the plant you see is a _____. a. triploid endosperm b. haploid gametophyte c. haploid sporophyte d. diploid sporophyte e. diploid gametophyte

diploid sporophyte

Cystic fibrosis is a genetic disorder in homozygous recessives that causes death during the teenage years. If 9 in 10,000 newborn babies have the disease, what are the expected frequencies of the dominant (A1) and recessive (A2) alleles according to the Hardy-Weinberg equation? a. f(A1) = 0.9800, f(A2) = 0.0200 b. f(A1) = 0.9997, f(A2) = 0.0003 c. f(A1) = 0.9700, f(A2) = 0.0300 d. f(A1) = 0.9604, f(A2) = 0.0392

f(A1) = 0.9700, f(A2) = 0.0300

True or false? Heterozygote advantage refers to the tendency for heterozygous individuals to have better fitness than homozygous individuals. This higher fitness results in less genetic variation in the population.

false

True or false? In most fungi, fertilization is complete after the cells fuse together.

false

In terms of alternation of generations, the internal parts of the pollen grains of seed-producing plants are most similar to a a. fern sporophyte. b. hermaphroditic fern gametophyte. c. moss gametophyte bearing both male and female gametangia. d. moss sporophyte. e. fern gametophyte bearing sperm.

fern gametophyte bearing sperm

Which group is noted for the independence of gametophyte and sporophyte generations from each other? a. charophytes b. mosses, hornworts, and liverworts c. angiosperms d. ferns e. gymnosperms

ferns

_____ are an example of seedless vascular plants. a. Pine trees b. Mosses c. Charophyceans d. Lilacs e. Ferns

ferns

The diploid phase of the life cycle is shortest in which of the following? a. fungus b. fern c. moss d. gymnosperm e. angiosperm

fungus

Workers from a nearby greenhouse accidentally introduce white flower seeds into this population's habitat

gene flow, frequency of white allele increases

A storm kills many plants at random

genetic drift, allele frequencies change but not predictably

A person uproots the five closest plants, which all happen to have white flowers

genetic drift, frequency of purple allele increases

Angiosperms are most closely related to _____. a. bryophytes b. green algae c. gymnosperms d. seedless vascular plants e. charophyceans

gymnosperms

Which of these was the dominant plant group at the time that dinosaurs were the dominant animals? a. bryophytes b. gymnosperms c. charophyceans d. seedless vascular plants e. angiosperms

gymnosperms

In the United States and Canada, bats use one of two strategies to survive winter. They either migrate south, or they hibernate. Recently, those that hibernate seem to have come under attack by a fungus, Geomyces destructans (Gd), an attack that is occurring from Missouri to New England, Canada, and even the state of Washington. Many infected bats have a delicate, white filamentous mat on their muzzles, which is referred to as white-nose syndrome (WNS). The fungus invades the bat tissues, causes discomfort, and awakens the bat from its hibernation. The bat fidgets and wastes calories, using up its stored fat. The bat then behaves abnormally, leaving its cave during daytime in winter to search for food. Their food, primarily insects, is scarce during the winter, and the bats ultimately starve to death. Since 2006, it is estimated that over six million bats have perished from WNS. The Gd mat on the fur of the bats should be expected to consist of ________. a. haustoria b. hyphae c. basidia d. yeasts

hyphae

What evolutionary development allowed plants to grow tall? a. sporophylls b. lignified vascular tissue c. rhizoids d. leaves e. the waxy cuticle

lignified vascular tissue

Basidia produce spores by a process known as _____. a. decomposition b. mitosis c. meiosis d. hyphae e. binary fission

meiosis

In mosses gametes are produced by _____; in ferns gametes are produced by _____. a. meiosis ... meiosis b. binary fission ... mitosis c. meiosis ... mitosis d. mitosis ... mitosis e. mitosis ... meiosis

mitosis ... mitosis

The sperm produced by mosses require _____ to reach an archegonium. a. moisture b. wind c. animals d. the development of a flower e. light

moisture

In life cycles with an alternation of generations, multicellular haploid forms alternate with a. unicellular diploid forms. b. multicellular haploid forms. c. unicellular haploid forms. d. multicellular diploid forms. e. multicellular polyploid forms.

multicellular diploid forms.

Some fungal species live in plants and can kill herbivores that feed on the plant. What type of relationship does this fungus have with its host? a. parasitic b. commensal d. predatory e. mutualistic

mutualistic

Which structure allows the growing mushroom to nourish itself? a. Basidia b. Mycelium c. Gills d. Spore

mycelium

Which structure is not directly involved in the reproduction of at least one major group of fungi? a. Asci b. Motile spores c. Basidium d. Mycelium

mycelium

Plants with purple flowers attract more insects, which pollinate the plants

natural selection, frequency of purple allele increases

During an extreme heat wave, plants with white flowers survive better

natural selection, frequency of white allele increases

The three major mechanisms of evolution differ in how they work, and as a result often have different effects on a population. Review your understanding of natural selection, genetic drift, and gene flow by sorting the statements below into the correct bins.

natural selection: 1. consistently causes a population to become better adapted to its environment 2. a result of differential success in reproduction 3. cannot cause a harmful allele to become more common genetic drift: 1. causes allele frequencies to fluctuate randomly 2. responsible for the founder effect 3. responsible for the bottleneck effect gene flow: 1. can introduce new alleles into a population's gene pool 2. a result of the movement of fertile individuals or their gametes

Which term describes the fusion of cytoplasm from two individuals? a. Plasmogamy b. Spore c. Heterokaryotic d. Karyogamy

plasmogamy

In addition to seeds, which of the following characteristics are unique to the seed-producing plants? a. vascular tissue b. use of air currents as a dispersal agent c. pollen d. lignin present in cell walls

pollen

The adaptation that made possible the colonization of dry land environments by seed plants is most likely the result of the evolution of _____. a. cones b. pollen c. ovules d. heterospory

pollen

The major difference between angiosperms and gymnosperms comes from the _____. a. presence or absence of vascular structures b. presence or absence of alternation of generations c. dominance or lack of dominance of the sporophyte generation d. production of microspores versus megaspores e. presence or absence of a protective covering over the ovule

presence or absence of a protective covering over the ovule

Fungi of the phylum Ascomycota are recognized on the basis of their production of _____ during sexual reproduction. a. a dikaryotic structure b. flagellated zoospores c. saclike structures d. lichens e. yeasts

saclike structures

According to the Hardy-Weinberg theorem, the frequencies of alleles in a population will remain constant if _____ is the only process that affects the gene pool. a. mutation b. sexual reproduction c. sexual selection d. immigration e. genetic drift

sexual reproduction

In contrast to bryophytes, in vascular plants the dominant stage of the life cycle is the _____. a. sporophyte b. archegonium c. spore d. antheridium e. gametophyte

sporophyte

Fungi release digestive enzymes into their _____. a. surroundings b. gastrovascular cavity c. stomach d. hyphae e. mycelia

surroundings

Whenever diploid populations are in Hardy-Weinberg equilibrium at a particular locus a. this means that, at this locus, two alleles are present in equal proportions. b. natural selection, gene flow, and genetic drift are acting equally to change an allele's frequency. c. the allele's frequency should not change from one generation to the next, but its representation in homozygous and heterozygous genotypes may change. d. the population itself is not evolving, but individuals within the population may be evolving.

the allele's frequency should not change from one generation to the next, but its representation in homozygous and heterozygous genotypes may change.

True or false? Most of the cells in a mushroom contain haploid nuclei.

true