BIO 121 Exam 3

microphyll

A ______________ is a small, often spine-shaped leaf of a lycophyte supported by a single strand of connective tissue.

postzygotic; reduced hybrid fertility

A horse and a donkey can reproduce successfully, producing a mule. However, the mule is sterile. This is an example of a __________ barrier called __________. postzygotic; reduced hybrid viability prezygotic; gametic isolation postzygotic; hybrid breakdown postzygotic; reduced hybrid fertility prezygotic; mechanical isolation

the bottleneck effect

A hurricane hits a small island, killing all but a few members of a bird population. This is an example of __________.

a region in which members of different species meet and mate, producing at least some offspring of mixed ancestry

A hybrid zone is defined as __________. None of the listed responses is correct. a region in which reproductive isolation prevents hybrids from being produced a region in which allopatric speciation occurs a region in which only hybrids are produced a region in which members of different species meet and mate, producing at least some offspring of mixed ancestry

32 In this situation, the gametes from the parents would be n = 7 and n = 9. They would combine for a total of 9, which after doubling is 18.

A new species of plant arises as an allopolyploid from two other plants, one with a diploid number of 14 and one with a diploid number of 18. What would the diploid number of the new species most likely be?

18 In this situation, the gametes from the parents would be n = 3 and n = 6. They would combine for a total of 9, which after doubling is 18.

A new species of plant evolved by allopolyploidy from two species of plant that are 2n = 6 and 2n = 12. What would the diploid number of chromosomes be in this new species?

An error in cell division occurred in the known species, leading to the development of an autopolyploid tetraploid offspring that evolved into the new species.

A new species of plant is discovered that closely resembles a known species. Upon further examination, it is discovered that the new species has a tetraploid number of 4n = 12, while the known species has a diploid number of 2n = 6. Which of the following statements provides a reasonable explanation for the evolution of this new species of plant? Four gametes from the known species of plant all fused to form the new species. None of the listed responses is correct. A geographic barrier separated a population of the known species, leading to the evolution of the new species. Gametes from two different species of plant that are both 2n = 6 mated and produced a new plant with 2n = 12. An error in cell division occurred in the known species, leading to the development of an autopolyploid tetraploid offspring that evolved into the new species.

regot

A parasitic fungus that attacks rye plants produces a structure called a(n) ________.

an ovary; an ovule

A pea pod is formed from __________. A pea inside the pod is formed from __________. endosperm; an ovary an ovary; a pollen grain an ovule; a carpel an ovary; an ovule an anther; an ovule

pollen grains are transferred to a flower on a different plant

A plant is said to be cross-pollinated if __________.

Disruptive Selection Disruptive selection favors individuals at both ends of the phenotypic spectrum.

A population of squirrels is preyed on by small hawks. The smaller squirrels can escape into burrows. The larger squirrels can fight off the hawks. After several generations, the squirrels in the area tend to be very small or very large. What process is responsible for this outcome?

Disruptive selection

A population of squirrels is preyed on by small hawks. The smaller squirrels can escape into burrows. The larger squirrels can fight off the hawks. After several generations, the squirrels in the area tend to be very small or very large. What process is responsible for this outcome?

the founder effect

A storm separates a small number of birds in a migrating population. These birds end up at a destination different from where they usually migrate and establish a new population in this new area. This is an example of __________.

biological species concept

According to the __________, a species is a group of populations whose members have the potential to interbreed in nature and produce viable, fertile offspring—but do not produce viable, fertile offspring with members of other such groups. biological species concept macroevolution ecological species concept phylogenetic species concept morphological species concept

the tempo of evolution consists of abrupt episodes of speciation among long periods of equilibrium

According to the punctuated equilibrium model of evolution, __________.

natural selection

All of the following conditions are required for Hardy-Weinberg equilibrium except __________.

radial; deuterostome

An animal with a true coelom that has __________ cleavage must be a __________.

Cretaceous The Cretaceous ended about 65 million years ago with mass extinctions of dinosaurs and many other animal groups and further increases in the diversity and importance of angiosperms.

Angiosperms are thought to have originated in which period? Silurian Paleogene Triassic Ordovician Cretaceous

Directional selection

Antibiotic resistance in bacteria is an example of which of the following?

form branching hyphae by invaginating through the cell wall of the roots

Arbuscular mycorrhizal fungi ___________.

200

At current rates of deforestation, tropical rain forests will be eliminated in __________ years.

Whole-gene The molecular level describes genetic variation as nucleotide variability. Although populations do vary in their characteristics, it is at the gene level that genetic variation can be quantified. Although species do vary in their characteristics, it is at the gene level that genetic variation can be quantified. Individuals may vary in a population, but it is at the gene level that genetic variation can be quantified.

At what level does gene variability quantify genetic variation?

Gene pool changes establish reproductive barriers between two populations.

At which point in the adaptation of a population is it clear that speciation has occurred? Gene pool changes establish reproductive barriers between two populations. Gene pool changes adapt a population to a local environment. An allopatric separation occurs. Viable, fertile hybrids occur. All of the listed responses are correct.

A large population is required for Hardy-Weinberg equilibrium. A population without mutations is required for Hardy-Weinberg equilibrium. A population without gene flow is required for Hardy-Weinberg equilibrium. Random mating in a population is required for Hardy-Weinberg equilibrium.

Conditions for the Hardy-Weinberg equation

xylem

Conduction of water and minerals is carried out by

Phylum Gnetophyta

Dietary supplements and decongestants containing ephedrine have recently become more strongly regulated in the United States. Ephedrine is an extract of a plant belonging to which phylum?

Karyogamy This is the only time in the life cycle of a fungus that diploid cells exist.

During what stage of fungal reproduction are diploid cells produced?

form sheaths of hyphae over the surface of a plant's roots and extracellular spaces of the root cortex

Ectomycorrhizal fungi __________. form sheaths of hyphae over the surface of a plant's roots and extracellular spaces of the root cortex form branching hyphae by invaginating through the cell wall of the roots form branching hyphae by invaginating through the cell wall of the shoots are parasitic fungi form sheaths of hyphae over the surface of a plant shoots and extracellular spaces of the shoot cortex

Charophytes

Evidence suggests that land plants arose from within which protist lineage?

free-living, multicellular organisms Gametophytes are haploid. Gametophytes produce gametes. Gametophytes are involved in sexual reproduction. The underside of the leaf (frond) is where sori are found.

Fern gametophytes are __________.

the type of sexual structure they form

Fungal species are classified in a particular phylum based on __________.

secreting digestive enzymes into the environment and then absorbing the smaller compounds into their bodies

Fungi "eat" their food by ___________.

Opisthokonts

Fungi belong to the clade ___________.

lignin

Fungi in the phylum Basidiomycota are the most important decomposers of wood because of their ability to break down __________.

coenocytic By definition, the coenocytic condition results from the repeated division of nuclei without cytoplasmic division.

Fungi that consist of a continuous mass containing hundreds or thousands of nuclei are known as __________. coenocytic imperfect fungi dikaryotic septic chytrids

a protonema (plural, protonemata).

Germinating moss spores characteristically produce a mass of green, branched, one-cell-thick filaments known as ____________

The expected frequency of the homozygous recessive genotype is represented by q2. The expected frequency of the homozygous dominant genotype is represented by p2. The expected frequency of the dominant allele is represented by p. The expected frequency of the recessive allele is represented by q.

Hardy-Weinberg variables

are specialized hyphae of both mutualistic and parasitic fungi

Haustoria _________. are specialized hyphae of mutualistic fungi are specialized hyphae of both mutualistic and parasitic fungi are specialized hyphae of parasitic fungi form symbiotic relationships with lichens are the fruiting bodies of asexual fungi

By mitosis of gametophyte cells

How are gametes produced by bryophytes? By meiosis of spores By meiosis of gametophyte cells By mitosis of gametophyte cells By meiosis of sporophyte cells By mitosis of spores

There is no set number

How many genes must change in order to form a new species? 1 There is no set number of genes or loci that produces a new species. Genetic and environmental factors interact. 14 4 26

...

Hyphae with two nuclei per cell are called __________.Hyphae with two nuclei per cell are called __________.

Individuals from the different populations sometimes mate with each other, but all of the resulting eggs are sterile.

Imagine that part of a population of South American finches is blown by a storm onto an island far offshore and manages to survive and reproduce there for a period of 10,000 years. After that period, a climate change results in lower sea levels and the reconnection of the island with the mainland. Members of the formerly isolated island finch population can now interact freely with members of the original mainland population. Which of the following observations would, by itself, lead you to conclude unequivocally that the island finch population had evolved into a distinct species, according to the biological species concept?

sympatric speciation

In __________ _______________, speciation occurs in populations that live in the same geographic area.

32% The 4% born with sickle-cell disease are homozygous for the sickle hemoglobin allele, so q2 = 0.04 and q = 0.2. Because p = 1 - q, p = 0.8. The heterozygotes would be equal to 2pq, or 0.32 (32%).

In a certain group of African people, 4% are born with sickle-cell disease (homozygous recessive). If this group is in Hardy-Weinberg equilibrium, what percentage of the group has the selective advantage of being more resistant to malaria (heterozygous) than those individuals who are homozygous for normal hemoglobin or for sickle-cell disease?

the frequency of the homozygous dominants will go down, the frequency of the heterozygous genotype will go down, and the frequency of the homozygous recessives will go up

In a large population of randomly breeding organisms, the frequency of a recessive allele is initially 0.3. There is no migration and no selection. Humans enter this ecosystem and selectively hunt individuals showing the dominant trait. When the gene frequency is reexamined at the end of the year, __________. the frequency of the homozygous dominants will go up, the frequency of the heterozygous genotype will go down, and the frequency of the homozygous recessives will go down the frequency of the homozygous dominants will go up, the frequency of the heterozygous genotype will go down, and the frequency of the homozygous recessives will go up the frequency of the homozygous dominants will go down, the frequency of the heterozygous genotype will go up, and the frequency of the homozygous recessives will remain the same the frequency of the homozygous dominants will go down, the frequency of the heterozygous genotype will remain the same, and the frequency of the homozygous recessives will go up the frequency of the homozygous dominants will go down, the frequency of the heterozygous genotype will go down, and the frequency of the homozygous recessives will go up

.20

In a population that is in Hardy-Weinberg equilibrium, 64% of the individuals express the recessive phenotype for a particular gene locus. What is the expected frequency of the dominant allele in this population?

.8

In a population that is in Hardy-Weinberg equilibrium, 64% of the individuals express the recessive phenotype for a particular gene locus. What is the expected frequency of the recessive allele in this population?

pollen

In addition to seeds, what is a trait unique to seed plants?

nuclei undergo mitosis without cytokinesis

In coenocytic hyphae, __________.

anther

In flowers, pollen is produced in the __________.

megaphylls

In sporophyte ferns, the leaves are __________. microphylls sporangia thalli megaphylls blades

the expected frequency of the heterozygous genotype

In the Hardy-Weinberg equation, 2pq represents __________.

the expected frequency of the homozygous recessive genotype

In the Hardy-Weinberg equation, q2 represents __________.

sexual selection Experiments have shown that females select mates on the basis of coloration. This behavioral isolation may have been a major factor in the speciation of cichlids.

In the case of the Lake Victoria cichlids, sympatric speciation has been shown to be driven by __________. sexual selection mechanical isolation postzygotic barriers polyploidy habitat differentiation

Evolution is a change in a population's allele frequencies over generations.

In the context of populations, how do we define evolution?

sporophylls

In vascular plants, _________ are modified leaves that bear sporangia.

Megasporangia produce spores that develop into female gametophytes, whereas microsporangia produce spores that develop into male gametophytes.

In what way do megasporangia differ from microsporangia?

All Vascular plants

In which group is the sporophyte stage dominant in the alternation of generations? All vascular plants Only the ferns All land plants Only seed plants Only nonvascular plants

Plants

In which of the following groups has sympatric speciation been most important? Protozoa Plants Fungi Bacteria Animals

a nucleariid.

It has been suggested that the fungal ancestor was ___________

they are important in the initial stages of soil formation

Lichens are important pioneers in areas that have been burned by fires or destroyed by lava flows because __________.

and animals have a common ancestor The evidence suggests that both fungi and animals evolved from aquatic flagellated protists.

Molecular evidence suggests that fungi __________.

hyphae

Multicellular fungal bodies are composed of ___________.

the reshuffling of alleles in sexual reproduction

No two people are genetically identical, except for identical twins. The main source of genetic variation among human individuals is __________.

Only the sperm of angiosperms combine with two central cell nuclei to form triploid endosperm.

Of the following, which is a difference in how reproduction occurs in gymnosperms compared to angiosperms? Only the sperm of angiosperms combine with two central cell nuclei to form triploid endosperm. Double fertilization only occurs in gymnosperms. Only angiosperm pollen grains form pollen tubes. Only angiosperms have reduced gametophytes. Only gymnosperms can contain male and female sporangia on the same plant.

neutral variation, differences in DNA sequence that do not confer a selective advantage or disadvantage.

Point mutations in noncoding regions of DNA result in __________.

contribute to reproductive isolation after a hybrid zygote has been formed

Postzygotic barriers __________. prevent a sperm from one species from fertilizing an ovum from another species lead to the development of viable, fertile hybrid organisms contribute to reproductive isolation after a hybrid zygote has been formed prevent individuals from two different species from mating contribute to reproductive isolation before a hybrid zygote has been formed

prevent fertilization of gametes from members of closely related species

Prezygotic barriers_____________ prevent fertilization of gametes from members of closely related species only occur in asexual organisms prevent donkeys and horses from mating prevent a hybrid zygote from developing into a viable, fertile adult are necessary in order for speciation to occur

speciation The "mystery of mysteries" that captivated Darwin is called speciation, the process by which one species splits into two or more species. Speciation fascinated Darwin (and many biologists since) because it has produced the tremendous diversity of life by repeatedly yielding new species that differ from existing ones. Speciation also helps to explain the many features that organisms share (the unity of life). When one species splits into two, the species that result share many characteristics because they are descended from this common ancestor.

Reproductive isolation is necessary for __________ to occur. polyploidy adaptation speciation mutation microevolution

meiosis Shuffling of chromosomes in meiosis contributes to sexual recombination. Three mechanisms contribute to this shuffling: crossing over, independent assortment of chromosomes, and fertilization. During meiosis, homologous chromosomes, one inherited from each parent, trade some of their alleles by crossing over. These homologous chromosomes and the alleles they carry are then distributed at random into gametes. Then, because myriad possible mating combinations exist in a population, fertilization brings together gametes that are likely to have different genetic backgrounds.

Sexual recombination includes the shuffling of chromosomes in __________ and fertilization.

sporangia

Spores are dispersed from the ________

favors intermediate variants in a population

Stabilizing selection __________. prevents mutations from occurring favors intermediate variants in a population usually results in two distinct phenotypes occurs only in plants occurs when some individuals migrate to an area with different environmental conditions

a geographic barrier splitting a population

Sympatric speciation typically occurs by all of the following mechanisms except __________.

sporophyte

The "dots" on the underside of a fern frond are spore cases; therefore, what is true of the plant to which the frond belongs?

glomeromycete

The __________ clade includes 160 species, with most producing arbuscular mycorrhizae.

sperm

The antheridia of mosses produce __________.

conidia

The asexual spores produced by members of the phylum Ascomycota are called __________.

behavioral isolation

The behavior of a male blue-footed boobie during the courtship ritual elicits no response from the masked boobie. The reproductive barrier between them is an example of __________. temporal isolation gametic isolation behavioral isolation reduced hybrid viability reduced hybrid fertility

chytrid

The decline of amphibian populations is most probably due to a(n) ________ parasite.

cuticle

The development of the __________ prevents plants from drying out and protects them from microbes. cuticle stomata flavonoid gametangia apical meristem

produces spores

The diploid generation of the plant life cycle always

allopatric speciation In allopatric speciation (from the Greek allos, other; patra, homeland), gene flow is interrupted when a population is divided into geographically isolated subpopulations. For example, the water level in a lake may subside, resulting in two or more smaller lakes that are now home to separated populations. Or a river may change course and divide a population of animals that cannot cross it. Allopatric speciation can also occur without geologic remodeling, such as when individuals colonize a remote area and their descendants become geographically isolated from the parent population.

The evolution of multiple species of snapping shrimp following the formation of the Isthmus of Panama is an example of __________. autopolyploidy sympatric speciation allopolyploidy All of the listed responses are correct. allopatric speciation I DON'T KNOW YET

mosses

The gametophyte stage of the plant life cycle is most conspicuous in __________.

all copies of every type of allele at every locus in all members of the population

The gene pool of a population consists of __________.

gametophyte

The haploid stage in plant alternation of generation is the _________

body shape and other structural features

The morphological species concept distinguishes species by __________. None of the listed responses is correct. body shape and other structural features reproductive isolation ecological niche common ancestry

micropyle

The pore in the integuments of an angiosperm ovule through which sperm is delivered is the __________.

...

The roundworm body cavity is ________, whereas the planarian body cavity is ________.

the heterozygote advantage

The sickle-cell allele, which is recessive, causes anemia but confers resistance to malaria in individuals who possess it. However, homozygous recessive individuals often die from anemia but not from malaria, and homozygous dominant individuals do not have anemia but could die from malaria. Heterozygous individuals have the highest relative fitness. This is an example of __________. the homozygous recessive advantage gene flow the homozygous dominant advantage genetic drift the heterozygote advantage

ecdysozoa, lophotrochozoa, and deuterstomia

The three major clades of bilaterian animals are the __________.

Distribution of sugars, amino acids, and other organic products

The tissue called phloem has what function in vascular plants?

develops a rough, thick-walled coating that can resist harsh conditions for months

The zygosporangium _________. is the asexual fruiting body of bread mold develops a rough, thick-walled coating that can resist harsh conditions for months produces spores by mitosis always contains monokaryotic nuclei is always a diploid structure

Temporal isolation

There are two groups of pine trees that appear to be very similar phenotypically and genotypically. However, one releases pollen in January, when the female structures of that group are receptive, and one in March. What kind of reproductive barrier is this? Hybrid inviability Gametic isolation Temporal isolation A geographic barrier Mechanical isolation

prezygotic; gametic isolation

Three species of sea stars all mate near the same reef by secreting their gametes into the water, but none of the gametes from the different species fertilize each other. This is an example of a __________ barrier called __________. prezygotic; temporal isolation prezygotic; habitat isolation prezygotic; gametic isolation postzygotic; hybrid breakdown postzygotic; reduced hybrid fertility

the sporangia

To examine meiosis in ferns, you would study __________.

Hybrid Breakdown Reduced hybrid fertility is a situation in which the hybrids are sterile. Reduced hybrid viability is a situation in which the hybrids do not survive or develop correctly. Gametic isolation occurs when gametes from different species do not fertilize each other. Mechanical isolation occurs when two species attempt to mate but are unsuccessful. Behavioral isolation occurs when two species' courtship rituals do not elicit any response from each other.

Two different species of frogs mate successfully and produce fertile hybrid offspring. However, the offspring of the hybrids do not develop completely to adulthood. This is an example of which type of reproductive barrier? reduced hybrid fertility behavioral isolation gametic isolation hybrid breakdown mechanical isolation reduced hybrid viability

peristome

Typically, the upper part of a bryophyte capsule that contains the spores features a ring of interlocking, tooth-like structures known as the __________.

Reproductive cells are more resistant to desiccation.

What is advantage is conferred to algae and plants that possess sporopollenin? Reproductive cells are more resistant to desiccation. Asexual reproduction is possible. Sexual reproduction can occur through the transfer of pollen. Spores are protected by toxins that deter consumption. The haploid stage of the life cycle can be eliminated.

Plasmogamy, karyogamy, meiosis, germination

What is the correct order of events in fungal sexual reproduction?

They increase the surface area for photosynthesis.

What is the evolutionary significance of megaphylls?

Gene flow between populations must be interrupted. Although several other factors come into play, as long as there is gene flow between populations, speciation is extremely unlikely. Speciation begins only after gene flow between populations is interrupted, perhaps by changing environmental conditions or by unpredictable events, such as a storm that transports a few individuals to an isolated area.

What is the first thing that must happen in order for speciation to occur? The populations must become reproductively isolated. Gene flow between populations must be interrupted. One of the populations must become polyploid. A hybrid zone must be established. A catastrophic event must cause geographic separation of two populations.

Arbuscules

What is the major feature of glomeromycetes? Arbuscules The containment of millions of photosynthetic microorganisms in their hyphae Ascocarps Soredia Mycorrhizae

the climate became drier and warmer

What significant change occurred on Earth between the Carboniferous period and the Permian period that most likely contributed to the success of the gymnosperms?

Stomata

What structures allow plants to readily take up carbon dioxide from the atmosphere? Stomata Mitochondria Capsules Cuticles Gametangia

speciation This is an example of separate species being created.

When gene flow between two populations ceases, the potential for __________ exists. sexual selection sexual reproduction hybridization speciation fusion

a group whose members share key biological features

When using terms such as coelomates and pseudocoelomates, a "grade" is _________.

The sperm of some gymnosperms have flagella.

Which example below is evidence provided by living gymnosperms of an evolutionary transition between seedless and seed plants? In gymnosperms, two sperms are discharged into the pollen tube. Gymnosperms only have one integument. The sperm of gymnosperms do not require water or mobility for fertilization. The sperm of some gymnosperms have flagella. Some gymnosperms do not have reduced gametophytes.

Cycadophyta

Which gymnosperm phylum below is characterized by large cones and fern-like leaves and thrived during the Mesozoic?

In plants, the haploid and diploid stages are both multicellular. The life cycle of humans, for example, includes a single-celled haploid stage and a multicellular diploid stage.

Which is a key difference between alternation of generations in plants and sexual reproduction in nonplant organisms? In plants, the haploid and diploid stages are both multicellular. In plants, the haploid generation is always dependent on the diploid generation. In plants, only the haploid stage is multicellular. In other sexually reproducing organisms, the haploid and diploid generations are both multicellular. In other sexually reproducing organisms, the fusion of gametes forms a zygote before an embryo.

All of the listed traits of land plants are present in their closest relatives among the algae.

Which of the following are traits shared by land plants and their closest relatives among the algae? All of the listed traits of land plants are present in their closest relatives among the algae. All the listed traits evolved exclusively in land plants. Formation of a phragmoplast Rings of cellulose-synthesizing proteins in the plasma membrane Structure of flagellated sperm

Mutation

Which of the following can form entirely new alleles?

Double Fertilization

Which of the following is a trait possessed by all angiosperms? Pollination by animals Double fertilization Seeds dispersed by animals Free-living gametophyte Seeds produced in ovulate cones

Two fruit flies of different species produce sterile offspring.

Which of the following is an example of a postzygotic reproductive barrier? One species of flower grows in forested areas, another in meadows. Two fruit flies of different species produce sterile offspring. Two pheasant species perform different courtship dances. The sperm of a marine worm can only penetrate eggs of the same species. One species of frog mates in April, but another mates in May.

male gametophyte

Which of the following is enclosed within the pollen wall of a pollen grain?

asexual reproduction

Which of the following is not an advantage seeds provide over spores? Asexual reproduction Multicellularity Stored food supply Long period of dormancy Protective integument

Wind blows pollen from one population of plants to another and cross-fertilization occurs.

Which of the following is the best example of gene flow?

Pine trees Pine trees in Alaska and pine trees on the island of Madagascar exhibit geographic isolation that could lead to allopatric speciation, for it is unlikely that pollen from one locale could get to the other locale.

Which of the following organisms is most likely to be subject to allopatric speciation? Bacteria in a hospital and bacteria in a nursery Mountain lions in the canyons of Wyoming and in the canyons of Utah Fruit flies on bananas and fruit flies on oranges Pine trees in Alaska and pine trees on the island of Madagascar Whale populations of the same species located on opposite sides of the Atlantic Ocean

Mechanical isolation With mechanical isolation, mating cannot occur successfully due to incompatibility of reproductive parts.

Which of the following reproductive barriers actually prevents individuals of closely related species from copulating successfully?

Mechanical isolation Mechanical isolation actually prevents individuals of closely related species from copulating successfully. With mechanical isolation, mating cannot occur successfully due to incompatibility of reproductive parts.

Which of the following reproductive barriers actually prevents individuals of closely related species from copulating successfully? Mechanical isolation Hybrid breakdown Hybrid sterility Gametic isolation Hybrid inviability

Plants have a waxy, waterproof cuticle, and algae do not.

Which of the following statements about algae and plants is true? Plants have a waxy, waterproof cuticle, and algae do not. Plants are multicellular, whereas algae are unicellular. Algae have different types of chlorophyll molecules from plants. Plant cells have rigid cellulose walls, and algal cells do not. Both plant and algal zygotes develop into embryos.

all

Which of the following statements correctly describe(s) characteristics of genetic drift? All of the listed responses are correct. It can lead to a loss of genetic variation in a population. It can cause allele frequencies to change at random. It can cause harmful alleles to become fixed in a population. It is significant in small populations.

Allele and genotype frequencies in the population will remain constant from generation to generation.

Which of the following statements correctly describes a population in Hardy-Weinberg equilibrium? Allele and genotype frequencies in the population will remain constant from generation to generation. All of the listed responses are correct. The population is evolving. The population exhibits no genetic variation. Allele and genotype frequencies in the population change from generation to generation.

Species tend to change rapidly in a short period of time.

Which of the following statements correctly describes one aspect of the punctuated model of evolution? Species tend to change slowly over a long period of time. Species change rapidly many times over a long period of time. None of the listed responses is correct. Species do not change at all. Species tend to change rapidly in a short period of time.

sexual selection can result in sexual dimorphism-- marked differences between the sexes in secondary sexual characteristics that are not directly associated with reproduction

Which statement below is true about sexual selection?

Duplication An important source of variation begins when genes are duplicated due to errors in meiosis (such as unequal crossing over), slippage during DNA replication, or the activities of transposable elements.

Which type of mutation plays the most important role in increasing the number of genes in the gene pool? Point mutation Duplication Mutations are so rare that there are no mutations that can have such an important effect. Rearrangement of gene loci Changes in nucleotide sequence

balancing selection

Which type of selection maintains stable frequencies of two or more phenotypic forms in a population?

dikaryotic cells with haploid nuclei basidiocarps are not monokaryotic and are not diploid.

While hiking through a forest, you discover a fungus growing on the remains of a decaying tree trunk. You hypothesize that it is a basidiomycete fungus because it resembles a mushroom in shape and size. If your logic is correct, microscopic analysis of the tissue found in the stalk of this fungus will reveal the presence of __________.

Lichens

__________ are symbiotic associations of algae and fungi.

Protonema

__________ are the masses of one-cell-thick filaments through which moss spores absorb water and minerals.

Archegonia

__________ are the structures of a moss that produce and house eggs.

Sporopollenin

__________ is a durable polymer that prevents the exposed zygotes of algae from drying out.

Polyploidy

___________ is when an accident during cell division occurs that results in extra sets of chromosomes in an individual.

Mycorrhizae

____________ are mutualistic associations of fungi and plants.

Adaptation

____________ is a characteristic that increases an individual's chance of survival and reproduction.

Microevolution

____________ is the change in allele frequencies in a population and does not always lead to reproductive isolation or speciation.

Strobili

_____________ are cone-like structures of lycophytes and most gymnosperms comprised of modified leaves that bear sporangia.

Mutation

_________________ is a change in an individual's DNA sequence.

asci

sexual spores of members of the phylum Asomycota are produced within structures called _________