bio 102 unit 4 cumulative practice

Why is the filamentous morphology of the slime molds considered a case of convergent evolution with fungi?

DNA sequence analyses indicate that slime molds descended from different unicellular ancestors than did fungi.

Which statement about the beak size of finches on the island of Daphne Major during prolonged drought is true?

Each bird's survival was strongly influenced by the depth and strength of its beak as the drought persisted.

How did Mendel's model of inheritance help explain Darwin's theory of natural selection?

by proposing a mechanism of how organisms could transmit discrete, heritable units to offspring

How can genetic variation at the whole gene level (gene variability) be quantified?

by the average percentage of loci that are heterozygous

Multicellular colonies of plant cells adhere to each other primarily by ________, whereas multicellular colonies of animal cells are typically held together by ________.

cell walls; proteins

The evolution of multicellularity in animals required adaptations that promoted

cellular adhesion and intercellular communication.

According to our current knowledge of plant evolution, which group of organisms should feature mitosis most similar to that of land plants?

charophytes

Which of the following was derived from an ancestral cyanobacterium?

chloroplast

Which process in sexual reproduction results in diversity at the nucleotide level?

chromosome crossover

Which of the following pairs of protists and their characteristics are mismatched?

ciliates−−red tide organisms

In a sample of pond water, a new organism is identified with the following characteristics: It consists of 70 cells surrounded by rigid cell walls that join the cells together. Inside each of these identical cells are mitochondria and chloroplasts. Such an organism would most likely be classified as a

colonial photosynthetic eukaryote.

Fossil fungi date back to the origin and early evolution of plants. What combination of environmental and morphological change is similar in the evolution of both fungi and plants?

colonization of land and loss of flagellated cells

In a population of 200 seagulls, dark brown feathers are dominant to having only white feathers. If 160 of the 200 seagulls have brown feathers, what is the frequency of seagulls that are homozygous dominant?

31%

The leaflike appendages of moss gametophytes may be one to two cell layers thick. Consequently, which of the following is least likely to be found associated with such appendages?

stomata

Whenever diploid populations are in Hardy-Weinberg equilibrium at a particular locus,

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

The flagella of choanocyte cells in a sponge are most similar in basic function to

the cilia of the trachea, moving mucous, dirt, and any liquid out of the human lung.

Anopheles mosquitoes, which carry the malaria parasite, cannot live above elevations of 5,900 feet. In addition, oxygen availability decreases with higher altitude. Consider a hypothetical human population that is adapted to life on the slopes of Mt. Kilimanjaro in Tanzania, a country in equatorial Africa. Mt. Kilimanjaro's base is about 2,600 feet above sea level, and its peak is 19,341 feet above sea level. If the incidence of the sickle-cell allele in the population is plotted against altitude (feet above sea level), which of the following distributions is most likely, assuming little migration of people up or down the mountain?

the graph with a diagonal line going from the upper left corner to the bottom right corner

In a Hardy-Weinberg population with two alleles, A and a, that are in equilibrium, the frequency of the allele a is 0.3. What is the frequency of individuals that are homozygous for this allele?

0.09

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?

0.80

Which of the following were benefits to algae in the early oceans of Earth, compared to the first plants that colonized land? 1. no scarcity of water 2. less solar damage to tissues 3. the need for structural support 4. more plentiful dissolved carbon dioxide

1 and 2 only

Please use the following information to answer the question below. The most recently discovered phylum in the animal kingdom (1995) is the phylum Cycliophora. It includes three species of tiny organisms that live in large numbers on the outsides of the mouthparts and appendages of lobsters. When in the feeding stage, a cycliophoran permanently attaches to the lobster via an adhesive disk and collects scraps of food from its host's feeding by capturing the scraps in a current created by a ring of cilia. Its body is sac-like and has a U-shaped intestine that brings the anus close to the mouth. Cycliophorans are eucoelomate (have a body cavity that is a coelom) and do not molt (though their host does). Basing your inferences on information in the paragraph, to which clade(s) should cycliophorans belong? 1. Eumetazoa 2. Deuterostomia 3. Bilateria 4. Ecdysozoa 5. Lophotrochozoa

1, 3, and 5 only

Evidence indicates that plants increase the number of stomata in their leaves as atmospheric CO2 levels decline. Increasing the number of stomata per unit surface area should have the effect of doing which of the following? 1. increasing dehydration of leaf tissues 2. decreasing dehydration of leaf tissues 3. countering the effect of declining CO2 on photosynthesis 4. reinforcing the effect of declining CO2 on photosynthesis 5. decreasing the O2 content of air next to the leaves lower than it would otherwise be 6. increasing the O2 content of air next to the leaves higher than it would otherwise be

1, 3, and 6 only

Assuming that they all belong to the same plant, arrange the following structures from largest to smallest (or from most inclusive to least inclusive). 1. spores 2. sporophytes 3. sporangia

2, 3, 1

The frequency of a disease is 30/1000. This is a disease that follows a dominant/recessive pattern of inheritance on one gene (where the only affected individuals are all homozygous recessive). What is the frequency of the disease genotype q2?

3%

Fossil evidence indicates that the following events occurred in what sequence, from earliest to most recent? 1. Protostomes invade terrestrial environments. 2. Cambrian explosion occurs. 3. Deuterostomes invade terrestrial environments. 4. Vertebrates become top predators in the seas.

2 → 4 → 1 → 3

Phenylketonuria (PKU) is a birth defect that causes an amino acid called phenylalanine to build up in the body. The frequency of individuals born in a population with PKU is q 2. There is one PKU (q 2) birth per 10,000 births. The frequency of the recessive allele for PKU in this population is q = 0.01. The frequency of the dominant allele in this population is p = 1 −− q = 0.99. What is the frequency of carriers (2pq) in this population?

2%

Arrange the following terms from most inclusive to least inclusive. 1. embryophytes 2. green plants 3. seedless vascular plants 4. ferns

2, 1, 3, 4

Which of the following is the most likely sequence of events, from earliest to most recent, in the evolution of sponges (organisms with many cells that have different functions)?1. single-celled eukaryote2. single-celled prokaryote3. multicellular eukaryote4. colonial eukaryote

2, 1, 4, 3

What does scientific evidence indicate to be the correct sequence of these events, from earliest to most recent, in the evolution of life on Earth? 1. origin of mitochondria 2. origin of multicellular eukaryotes 3. origin of chloroplasts 4. origin of cyanobacteria 5. origin of fungal-plant symbioses

4, 1, 3, 2, 5

In a population of 200 mice, brown fur is dominant to gray fur. If 120 of the 200 mice have brown fur, what is the frequency of mice that are heterozygous?

46%

If, on average, 46% of the loci in a species' gene pool are heterozygous, then the average homozygosity of the species should be

54%.

Which statement about variation is true?

All new alleles are the result of nucleotide variability.

Of the four supergroups of eukaryotes, which one contains red algae, green algae, and all land plants?

Archeplastida

Blue light is a portion of the visible spectrum that penetrates deep into bodies of water. Ultraviolet (UV) light, though, can penetrate even deeper. A gene within a population of marine fish that inhabits depths from 500 m to 1,000 m has an allele for a photopigment that is sensitive to UV light and another allele for a photopigment that is sensitive to blue light. Which of the graphs in the figure best depicts the predicted distribution of these alleles within a population if the fish that carry these alleles prefer to locate themselves where they can see best?

B, the graph with an X with blue on top and uv on bottom

Which of the following animal groups is entirely aquatic?

Echinodermata

Diatoms are mostly asexual members of the phytoplankton. They obtain their nutrition from functional chloroplasts, and each diatom is encased within two porous, glasslike valves. Which question would be most important for one interested in the day-to-day survival of individual diatoms?

How do diatoms with their glasslike valves keep from sinking into poorly lit waters?

Which of the following organism pairs is/are an example of secondary endosymbiosis? I. red algae−−heterotrophic eukaryote II. green algae−−heterotrophic eukaryote III. E. coli bacteria−−photosynthetic cyanobacterium IV. Chlamydomonas and Gonium

I and II

Rhizarians that feed using threadlike pseudopodia include which of the following group(s)?I. foramsII. red algaeIII. cercozoansIV. green algae

I and IIIII and IV

Challenges for survival of the first land plants include I. sources of water. II. sperm transfer. III. desiccation.I V. animal predation. V. lack of structural support.

I, II, III, and V only

The theory of endosymbiosis and history of life on Earth allows one to predict that the gene sequences that are responsible for encoding functional, mitochondrial ribosomes in a particular tree likely share many similar nucleotides in the sequences from the ribosomal genes ofI) other plant species.II) bacterial species.III) other tree species.

I, II, and III

The vegetative (nutritionally active) bodies of most fungi are I. composed of hyphae. II. referred to as a mycelium. III. usually underground.

I, II, and III

Which description(s) apply(ies) equally well to fungal spores produced both sexually and asexually? I. They are typically dispersed by wind and water. II. Spores that germinate produce new mycelium. III. They are produced in large numbers.

I, II, and III

Which of the following statements support(s) the theory of the endosymbiotic origin of mitochondria and plastids? I) Mitochondria and plastids have circular DNA and replicate by splitting. II) Mitochondria and plastids have ribosomes III) Mitochondrial and plastid ribosomal RNA sequences are more similar to cytoplasmic ribosomes than to bacterial ones. IV) The inner membranes of plastids and mitochondria have transport proteins homologous to those in bacterial plasma membranes.

I, II, and IV

Commonalities to both charophytes and vascular land plants include I. sporopollenin. II. lignin. III. chlorophyll a. IV. cellulose. V. chlorophyll b.

I, III, IV, and V only

Plasmogamy can directly result in which of the following? I. cells with a single haploid nucleus II. heterokaryotic cells III. cells with two diploid nuclei

II only

Adaptations in plants to life on land include I. rings of cellulose-synthesizing complexes. II. cuticles. III. tracheids. IV. reduced gametophyte generation. V. multicellular, dependent embryos.

II, III, IV, and V only

Which of the following is a true statement about plant reproduction?

In bryophytes, the dominant generation consists of haploid gametophytes.

Which statement is correct with regard to the comparison of secondary endosymbiosis to primary endosymbiosis?

In secondary endosymbiosis, an entire free-living alga is ingested into the food vacuole of a heterotrophic eukaryote.

An individual mixotroph loses its plastids yet continues to survive. Which of the following most likely accounts for its continued survival?

It engulfs organic material by phagocytosis or by absorption.

Which of the following is correct about genetic variation?

It must be present in a population before natural selection can act upon the population.

Which statement is correct with regard to the origins of multicellular organisms?

Multicellular organisms with differentiated cells likely originated from multiple different ancestors.

Recent research investigating variation in human height have found that a variety of genes at different loci, as well as early nutrition, especially that of the mother during gestation (the period of time during development of a fetus) and childhood years, influence height. Given this information, which of the following is correct?

Phenotypes are usually the result of a combination of genes as influenced by the environment.

Why don't similar genotypes always produce the same phenotype?

Phenotypes can vary depending upon environment

Which taxon is essentially equivalent to the "embryophytes"?

Plantae

The animal phylum most like the protists that gave rise to the animal kingdom is _____.

Porifera, Evidence that supports this includes the lack of true tissue in sponges and the close similarity between choanocytes and choanoflagellates.

Why can eukaryotes be considered "combination" organisms?

Some of their genes and cellular characteristics were derived from archaea, and others from bacteria.

Considering that the mature sporophytes of true mosses get their nutrition from the gametophytes on which they grow, and considering these generations as individual plants, what is true of the relationship between true moss sporophytes and gametophytes?

Sporophytes are parasites of gametophytes.

Imagine you predict a particular frequency for a genotype, based upon detailed knowledge of that genotype frequency in population "X" of a species. Then, using the Hardy-Weinberg model, you find that the observed genotype frequency in a different population, named "Y" of the same species, is not significantly different from what you predicted/expected based on population "X."Which of the following should you conclude?

The particular gene of interest is not undergoing any mechanisms of evolution.

Why is there controversy surrounding the eukaryotic tree?

The root of the tree is uncertain such that it is unknown which supergroup was the first to diverge from all other eukaryotes

Which of the following statements about dinoflagellates is correct?

They possess two flagella

Which of the following characteristics helped seedless plants better adapt to life on land?

a well-developed vascular system

Whatever its ultimate cause(s), the Cambrian explosion is a prime example of

adaptive radiation.

In a synthetic biology experiment, you are given a task to design a new species of aquatic protist. Your design should account for the following characteristics: 1. The protist functions as a primary producer.2. It cannot swim on its own.3. It must stay in well-lit surface waters.4. It must be resistant to physical damage from wave action. Based on these criteria, you decide to model your creation after a(n)

diatom

Immediately after karyogamy occurs, which term applies?

diploid

Which of the following describes a mechanism for generating more genes?

duplication

On a field trip, a student in a marine biology class collects an organism that has differentiated organs, cell walls of cellulose, and chloroplasts with chlorophyll a. Based on this description, the organism could be a brown alga, a red alga, a green alga, a charophyte recently washed into the ocean from a freshwater or brackish water source, or a land plant washed into the ocean. The presence of which of the following features would definitively identify this organism as a land plant?

embryos

Imagine you are investigating life in the shallow soils of a forest. In your collected samples, you observe evidence of various single-celled organisms using multiple genetic techniques as well as microscopy. If the organisms you initially assess possess mostly asymmetric or irregular forms, then this particular sample probably has many

eukaryotes

All protists are

eukaryotic

A snail-like, coiled, porous test (shell) of calcium carbonate is characteristic of which group?

foraminiferans

According to the endosymbiotic theory of the origin of eukaryotic cells, how did mitochondria originate?

from engulfed, originally free-living proteobacteria

When a mycelium infiltrates an unexploited source of dead organic matter, what are most likely to appear within the food source soon thereafter?

fungal enzymes

When pathogenic fungi are found growing on the roots of grape vines, grape farmers sometimes respond by covering the ground around their vines with plastic sheeting and pumping a gaseous fungicide into the soil. The most important concern of grape farmers who engage in this practice should be that the

fungicide might also kill mycorrhizae.

A botanist discovers a new species of land plant with a dominant sporophyte, chlorophylls a and b, and cell walls made of cellulose. In assigning this plant to a phylum, which of the following, if present, would be least useful?

spores

The Hardy-Weinberg equation p2 + 2pq + q2 = 1 allows you to calculate

genotype frequencies.

The chloroplasts of all of the following are thought to be derived from ancestral red algae, except those of

green algae.

In the formula for determining a population's genotype frequencies, the 2 in the term 2pq is necessary because

heterozygotes can come about in two ways based upon parental gametes.

In the formula for determining a population's genotype frequencies, the pq in the term 2pq is necessary because

heterozygotes have two alleles.

A large seaweed that floats freely on the surface of deep bodies of water would be expected to lack which of the following?

holdfasts

Mitotic activity by the apical meristem of a root makes which of the following more possible?

increased absorption of mineral nutrients

Both animals and fungi are heterotrophic. The fact below that distinguishes animal heterotrophy from fungal heterotrophy is that only animals derive their nutrition from

ingestion.

Which process occurs in fungi and has the opposite effect on a cell's chromosome number than does meiosis?

karyogamy

In seed plants, which of the following is part of a pollen grain and has a function most like that of the seed coat?

sporopollenin

The structural integrity of bacteria is to peptidoglycan as the structural integrity of plant spores is to

sporopollenin

It is estimated by a wide body of scientists that in recent decades we have begun another mass extinction event on Earth. Amphibians in particular have been in decline, sometimes due to climate change, and they therefore provide a possible early sign of dramatic biodiversity change to come. With respect to climate change and natural selection acting upon a population of one species of frog in a tropical rain forest, mutations of DNA sequences of the frog genome that are inherited by offspring

may have no effect at all, be beneficial, or be harmful.

Which of the following consistently improves the degree to which organisms are well suited for life in their environment?

natural selection

When using the Hardy-Weinberg equilibrium model, we assume that

natural selection is not occurring.

Using the figure, which of the following taxonomic groups from the list below would you expect to have a genome with DNA sequences most similar to the Plantae?

other charophytes

Some green algae exhibit alternation of generations. All land plants exhibit alternation of generations. No charophytes exhibit alternation of generations. Keeping in mind the recent evidence from molecular systematics, the correct interpretation of these observations is that

plants evolved alternation of generations independently of green algae.

If all fungi in an environment that perform decomposition were to suddenly die, then which group of organisms should benefit most, after their fungal competitors have been removed?

prokaryotes

Which of the following are the most abundant and diverse of the extant vertebrates?

ray-finned fishes

The functional role of sporopollenin is primarily to

reduce the dehydration of zygotes

Please use the following information to answer the question below. An elementary school science teacher decided to liven up the classroom with a saltwater aquarium. Knowing that saltwater aquaria can be quite a hassle, the teacher proceeded stepwise. First, the teacher conditioned the water. Next, the teacher decided to stock the tank with various marine invertebrates, including a sea star, a sponge, a sea urchin, a jellyfish, several hermit crabs, some sand dollars, and an ectoproct. Last, she added some vertebrates−−a parrotfish and a clownfish. She arranged for daily feedings of copepods and feeder fish. Had the teacher wanted to point out organisms that move and feed using the same structural adaptation, the teacher should have chosen the

sea star, sea urchin, and sand dollars.

A mutation that is neither harmful nor beneficial is termed a

silent mutation.

The last common ancestor of fungi and animals was most likely a

single-celled eukaryote.

The last common ancestor of all bilaterians is thought to have had four Hox genes (genes that regulate development of posterior-anterior axes and body segments). Most extant cnidarians have two Hox genes, except Nematostella, which has three Hox genes. On the basis of these observations, some have proposed that the ancestral cnidarians were originally bilateral and, in stages, lost Hox genes from their genomes. If true, this would mean that

the radial symmetry of extant cnidarians is secondarily derived rather than being an ancestral trait.

Which of these observations gives the most support to the endosymbiotic theory for the origin of eukaryotic cells?

the similarity in size between the cytosolic ribosomes of prokaryotes and the ribosomes within mitochondria and chloroplasts

Comparisons of choanoflagellate and animal genome sequences tell us that key steps in the transition to multicellularity in animals involved new ways of using proteins or parts of proteins that were encoded by genes found in

unicellular protists.

Please use the following information to answer the questions below.HIV's genome of RNA includes the code for reverse transcriptase (RT), an enzyme that acts early in infection to synthesize a DNA genome off an RNA template. The HIV genome also codes for protease (PR), an enzyme that acts later in infection by cutting long viral polyproteins into smaller, functional proteins. Both RT and PR represent potential targets for antiretroviral drugs. Drugs called nucleoside analogs (NA) act against RT, whereas drugs called protease inhibitors (PI) act against PR.Which of the following represents the treatment option most likely to avoid the production of drug-resistant HIV (assuming no drug interactions or side effects)?

using moderate doses of NA and two different PIs at the same time for several months

When evolution occurred on the Galápagos Islands, the finch beaks

varied in size across the population and sometimes conferred benefits in feeding, survivorship, and reproduction that were passed down to surviving offspring.

What is a population in biology?

when a group of individuals of the same species live in the same area and interbreed