Exam 4

Arrange the following terms from __most__ inclusive to __least__ inclusive. \n 1. green plants \n 2. vascular plants \n 3. seeded plants \n 4. gymnosperms 

  

2, 1, 4, 3

 

  

1, 2, 3, 4

 

  

2, 1, 3, 4

 

  

1, 2, 4, 3

 

1, 2, 4, 3

Which of the following is the most predictable outcome of increased gene flow between two populations?

  

decreased genetic difference between the two populations

 

  

increased genetic difference between the two populations

 

  

lower average fitness in both populations

 

  

higher average fitness in both populations

 

decreased genetic difference between the two populations

Which of these time intervals came last (most recently)?

  

colonization of land by mosses

 

  

rise and diversification of angiosperms

 

  

carboniferous swamps with giant ferns and related groups

 

  

extensive growth of gymnosperm forests

 

rise and diversification of angiosperms

Two species of frogs belonging to the same genus occasionally mate, but the embryos stop developing after a day and then die. These two frog species separate by _____.

  

gametic isolation

 

  

hybrid sterility

 

  

reduced hybrid fertility

 

  

reduced hybrid viability

 

gametic isolation

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

  

the population is diploid

 

  

the population is doubling in number

 

  

heterozygotes have two alleles

 

  

heterozygotes can come about in two ways

the population is diploid

Which of the following pairs are the best examples of homologous structures?

  

bones in the bat wing and bones in the human forelimb

 

  

eyelessness in the Australian mole and eyelessness in the North American mole

 

  

bat wing and bird wing

 

  

owl wing and hornet wing

 

bat wing and bird wing

Which of the following statements about genetic drift as an evolutionary factor is true?

 

It is more significant in a population with small numbers than in a population with large numbers.

  

It is responsible for the selection of mutations.

 

 

It is connected to the movements of alleles between populations of a single species.

 

 

Its strength is proportional to the size of a population: the larger the population, the greater the force.

It is more significant in a population with small numbers than in a population with large numbers.

Shared derived traits are also known as

  

synapomorphies.

 

  

homoplasies.

 

  

homologies.

 

  

sympatries.

 

synapomorphies.

During a study session about evolution, one of your fellow students remarks, "The giraffe stretched its neck while reaching for higher leaves; its offspring inherited longer necks as a result." Which statement is most likely to be helpful in correcting this student's misconception?

  

Spontaneous mutations can result in the appearance of new traits.

 

  

Only favorable adaptations have survival value.

 

  

Disuse of an organ may lead to its eventual disappearance.

 

 

Characteristics acquired during an organism's life are generally not passed on through genes.

Characteristics acquired during an organism's life are generally not passed on through genes.

The evolutionary relationship among organisms is known as

  

synapomorphy.

 

  

phylogeny.

 

  

paraphyly.

 

  

homoplasy.

 

phylogeny

Upon being formed, oceanic islands, such as the Hawaiian Islands, should feature what characteristic, leading to which phenomenon?

  

adaptive radiation, leading to founder effect

 

  

mass extinctions, leading to bottleneck effect

 

  

a variety of empty ecological niches, leading to adaptive radiation

 

  

major evolutionary innovations, leading to rafting to nearby continents

 

mass extinctions, leading to bottleneck effect

The cow *Bos primigenius* (which is bred for meat and milk) has a smaller brain and larger eyes than closely related wild species of ungulates. These traits most likely arose by _____. 

 

artificial selection, because changes in these traits co-occurred with human selection for high milk output and high muscle content

  

natural selection, because these traits were not consciously selected by humans

 

 

artificial selection, because these animals differ from their close relatives and common ancestor

  

natural selection, because these traits evolved in the population over time

artificial selection, because changes in these traits co-occurred with human selection for high milk output and high muscle content

The most direct ancestors of land plants were probably _____.

  

photosynthesizing prokaryotes (cyanobacteria)

 

  

mosses

 

  

green algae

 

  

kelp (brown alga) that formed large beds near the shorelines

green algae

 

Three populations of crickets look very similar, but the males have courtship songs that sound different. What function would this difference in song likely serve if the populations came in contact?

  

a behavioral reproductive isolating mechanism

 

  

a temporal reproductive isolating mechanism

 

  

a postzygotic isolating mechanism

 

  

a gametic reproductive isolating mechanism

 

a temporal reproductive isolating mechanism

 

How are two different species most likely to evolve from one ancestral species?

  

sympatrically, by a point mutation affecting morphology or behavior

 

  

allopatrically, after the ancestral species has split into two populations

 

  

sympatrically, due to extensive inbreeding

 

  

allopatrically, due to extensive inbreeding

 

sympatrically, due to extensive inbreeding

According to the scientific definition of the word theory, a theory is

  

a large body of knowledge.

 

  

a supposition.

 

  

largely a matter of guesswork.

 

  

a hypothesis.

 

a large body of knowledge.

 

Snakes, which lack limbs, evolved from vertebrates that had legs. This is an example of

  

a synapomorphy.

 

  

a homology.

 

  

an evolutionary reversal.

 

  

convergent evolution.

 

a homology.

Many crustaceans (for example, lobsters, shrimp, and crayfish) use their tails to swim, but crabs have reduced tails that curl under their shells and are not used in swimming. This is an example of _____.

  

a homologous structure

 

  

natural selection

 

  

a vestigial trait

 

  

convergent evolution

 

a vestigial trait

In hybrid zones where reinforcement is occurring, we should see a decline in _____.

  

gene flow between distinct gene pools

 

  

the genetic distinctness of two gene pools

 

  

mutation rates

 

  

speciation

 

 

the genetic distinctness of two gene pools

Which eukaryotic kingdom includes members that are the result of endosymbioses that included an ancient aerobic bacterium and an ancient cyanobacterium?

  

Protista

 

  

Plantae

 

  

Fungi

 

  

Animalia

 

Protista

In a comparison of birds and mammals, having four limbs is _____.

  

a character useful for distinguishing birds from mammals

 

  

a shared ancestral character

 

  

an example of analogy rather than homology

 

  

a shared derived character

 

a character useful for distinguishing birds from mammals

 

Based on cladistics, which eukaryotic kingdom is polyphyletic and, therefore, unacceptable?

  

Protista

 

  

Fungi

 

  

Animalia

 

  

Plantae

 

Protista

Geographical speciation is also known as 

  

reinforcement. 

  

Darwinian speciation. 

  

sympatric speciation. 

  

allopatric speciation.

sympatric speciation

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

 

natural selection, gene flow, and genetic drift are acting equally to change an allele's frequency

  

individuals within the population are evolving

 

  

two alleles are present in equal proportions

the allele's frequency should not change from one generation to the next

What does the biological species concept use as the primary criterion for determining species boundaries?

  

gene flow

 

  

niche differences

 

  

morphological similarity

 

  

geographic isolation

 

gene flow

 

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\.64

 

  

0\.75

 

  

0\.80

 

  

0\.36

 

0\.64

A large population of laboratory animals has been allowed to breed randomly for a number of generations. After several generations, 25% of the animals display a recessive trait (aa), the same percentage as at the beginning of the breeding program. The rest of the animals show the dominant phenotype, with heterozygotes indistinguishable from the homozygous dominants. What is the estimated frequency of allele A in the gene pool?

  

0\.50

 

  

0\.25

 

  

0\.75

 

  

0\.125

0\.75

Which of the following is the best modern definition of evolution?

  

change in the number of genes in a population over time

 

  

survival of the fittest

 

  

inheritance of acquired characters

 

  

descent with modification

 

descent with modification

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

  

23%

 

  

46%

 

  

92%

 

  54%

54%

 

The term homoplasy is most applicable to which of the following features?

  

the legless condition found in various lineages of extant lizards

 

  

the five-digit condition of human hands and bat wings

 

  

the bones of bat forelimbs and the bones of bird forelimbs

 

  

the fur that covers Australian moles and North American moles

 

the five-digit condition of human hands and bat wings

Which of the following statements about population bottlenecks is FALSE?

  

They are an extreme example of natural selection.

 

  

They arise from severe reductions in population size.

 

  

They can result in changes in allele frequencies.

 

  

They can result in the loss of genetic variation.

 

They are an extreme example of natural selection.

Which of the following lines of evidence would best support your assertion that a particular plant is an angiosperm?

  

It has fruit.

 

  

It lacks a cuticle.

 

  

It undergoes alternation of generations.

 

  

It produces seeds.

 

It has fruit.

 

What evidence do paleobotanists look for that indicates the movement of plants from water to land?

  

sporopollenin to inhibit evaporation from leaves

 

  

remnants of chloroplasts from photosynthesizing cells

 

  

loss of structures that produce spores

 

  

waxy cuticle to decrease evaporation from leaves

waxy cuticle to decrease evaporation from leaves

The biological species concept does NOT apply to which of the following groups of organisms?

  

Asexual fungi.

 

  

Mammals that form monogamous pair bonds

 

  

Fungi that engage in sexual reproduction

 

  

Birds

 

Asexual fungi.

A farmer uses triazine herbicide to control pigweed in his field. For the first few years, the triazine works well and almost all the pigweed dies; but after several years, the farmer sees more and more pigweed. Which of these explanations best explains what happened?

 

The herbicide company lost its triazine formula and started selling poor-quality triazine.

  

Triazine-resistant weeds were more likely to survive and reproduce.

 

 

Natural selection caused the pigweed to mutate, creating a new triazine-resistant species.

  

Triazine-resistant pigweed has less-efficient photosynthesis metabolism.

 

Triazine-resistant weeds were more likely to survive and reproduce.

 

Some beetles and flies have antler-like structures on their heads, much like male deer do. The existence of antlers in beetle, fly, and deer species with strong male-male competition is an example of _____.

  

homology

 

  

parsimony

 

  

convergent evolution

 

  

a synapomorphy

convergent evolution

The most common means of sympatric speciation occurs via

  

geographic barriers.

 

  

polyploidy.

 

  

reinforcement.

 

  

disruptive selection.

polyploidy.

 

Which of the following is formed when two branches diverge from one another in a phylogenetic tree?

  

A synapomorphy

 

  

A lineage

 

  

A node

 

  

A population

 

A synapomorphy

Currently the only predators of Galápagos marine iguanas are Galápagos hawks. Iguana body size is not correlated with risk of hawk predation, although small iguanas can sprint faster than large iguanas. If predators (for example, cats) that preferably catch and eat slower iguanas are introduced to the island, iguana body size is likely to _____ in the absence of other factors; the iguanas would then be under _____ selection.

  

increase; disruptive

 

  

decrease; disruptive

 

  

decrease; directional

 

  

increase; directional

 

decrease; directional

 

In a Hardy-Weinberg population with two alleles, A and a, that are in equilibrium, the frequency of allele a is 0.2. What is the frequency of individuals that are heterozygous for this allele?

  

0\.04

 

  

0\.16

 

  

0\.32

 

  

0\.020

0\.32

What accounts for HIV's rapid rate of evolution?

  

Its poor repair system causes it to have a high mutation rate.

 

  

It is subject to strong stabilizing selection.

 

  

Meiotic errors

 

  

Many viral particles are transmitted upon each infection.

 

Its poor repair system causes it to have a high mutation rate.

Which of the following must exist in a population before natural selection can act upon that population?

  

the population has predators

 

  

variation among individuals caused by environmental factors

 

  

genetic variation among individuals

 

  

sexual reproduction

 

genetic variation among individuals

 

Which of the following is NOT a condition for the Hardy-Weinberg equilibrium?

  

Absence of gene flow

 

  

Small population size

 

  

Absence of mutation

 

  

Random mating of individuals with respect to genotype

 

  

Absence of differential survival among genotypes

 

Small population size

Given the diversity of dog breeds that exists, which of the following principles is likely to be true?

  

C. The morphological traits seen must be at least somewhat heritable.

 

  

D. Both A and B

 

  

A. The original gene pool had little genetic variation.

 

 

B. Selection can yield considerable morphological change, outside the range of the original population.

  

E. Both B and C

 

 

E. Both B and C

As adaptions for flight, the wings of bats and the wings of birds are an example of

  

synapomorphy.

 

  

monophyly.

 

  

convergent evolution.

 

  

evolutionary reversal.

 

synapomorphy.

Both animals and fungi are heterotrophic. What distinguishes animal heterotrophy from fungal heterotrophy is that most animals derive their nutrition by _____.

  

ingesting it

 

  

preying on animals

 

consuming living, rather than dead, prey

 

  

using enzymes to digest their food

 

 

consuming living, rather than dead, prey

 

A decrease from pH 7.4 to pH 7.2 causes hemoglobin to _____.

  

increase its binding of H+

 

  

release all bound carbon dioxide molecules

 

  

give up more of its oxygen molecules

 

  

bind more oxygen molecules

 

give up more of its oxygen molecules

During fertilization, the acrosomal contents _____.

  

block polyspermy

  

digest the protective jelly coat on the surface of the egg

 

  

help propel more sperm toward the egg

 

  

trigger the completion of meiosis by the sperm

 

digest the protective jelly coat on the surface of the egg

Which of the following regarding the Spemann organizer is FALSE?

  

Signaling molecules from the organizer inhibit ventral development.

 

  

The organizer determines the dorsal-ventral axis.

 

  

The dorsal lip cells directly activate dorsal development.

 

  

The organizer forms in the area of the grey crescent.

 

The dorsal lip cells directly activate dorsal development.

Plant meristematic cells _____.

 

subdivide into three distinct cell types named parenchyma, ground meristem, and procambium

  

are distributed evenly in all tissues throughout the plant

 

are undifferentiated cells that produce new cells

 

  

increase the surface area of dermal tissue by developing root hairs

 

subdivide into three distinct cell types named parenchyma, ground meristem, and procambium

Which part of a plant absorbs most of the water and minerals taken up from the soil?

  

root hairs

 

  

the thick parts of the roots near the base of the stem

 

  

root cap

 

  

storage roots

 

root hairs

Arrange the following five events in an order that explains the mass flow of materials in the phloem. \n 1. Water diffuses into the sieve tubes. \n 2. Leaf cells produce sugar by photosynthesis. \n 3. Solutes are actively transported into sieve tubes. \n 4. Sugar is transported from cell to cell in the leaf. \n 5. Sugar moves down the stem. 

  

4, 2, 1, 3, 5

 

  

2, 4, 1, 3, 5

 

  

1, 2, 3, 4, 5

 

  

2, 4, 3, 1, 5

 

2, 4, 3, 1, 5

Once labor begins in childbirth, contractions increase in intensity and frequency, causing more contractions to occur until delivery. The increasing labor contractions of childbirth are an example of which type of regulation?

  

negative feedback

 

  

feedback inhibition

 

  

positive feedback

 

  

enzymatic catalysis

 

positive feedback

If the blastopore dorsal lip is grafted from one frog embryo onto a second embryo, the second dorsal lip will

  

induce salivary gland formation.

 

  

block gastrulation.

 

  

change the developmental fate of the surrounding cells.

 

  

cause rapid cell division.

change the developmental fate of the surrounding cells.

Which of the following statements regarding flowering plants is correct?

\
The gametophyte is the dominant generation.

 

  

Pollination is the delivery of pollen to the stigma of a carpel.

 

 

The food-storing endosperm is derived from the cell that contains one polar nucleus and two sperm nuclei.

  

Female gametophytes develop from megaspores within the anthers.

 

Pollination is the delivery of pollen to the stigma of a carpel.

Which of the following does NOT occur during cleavage?

  

Differential distribution of nutrients and information molecules

 

  

Cell growth

 

  

Rapid DNA synthesis

 

  

A rapid series of cell divisions

 

Cell growth

Which of the following flower parts develops into a seed?

  

carpel

 

  

stamen

 

  

ovule

 

  

anther

 

 

ovule

 

Structures as different as human arms, bat wings, and dolphin flippers contain many of the same bones, which develop from similar embryonic tissues. These structural similarities are an example of _____.

  

homology

 

  

the evolution of common structure as a result of common function

 

  

the evolution of similar appearance as a result of common function

 

\
  

convergent evolution

 

homology

___ in Fick's law is optimized by the large number of alveoli in mammalian lungs.

  

D

 

  

A

 

  

delta p

 

  

d

 

A

Most of the carbon dioxide produced by humans is _____.

  

transported in the erythrocytes as carbonic acid

 

\
  

converted to bicarbonate ions by an enzyme in red blood cells

 

  

simply dissolved in the plasma

 

  

bound to hemoglobin

converted to bicarbonate ions by an enzyme in red blood cells

Double fertilization results in the formation of

  

two diploid embryos.

 

  

two diploid embryos and a haploid endosperm.

 

  

one diploid embryo and a triploid endosperm.

 

  

one diploid embryo and a diploid endosperm.

 

one diploid embryo and a triploid endosperm.

Which characteristic is common to all the modern representatives of all major reptilian lineages (turtles, lizards, crocodiles, and birds)?

  

presence of a notochord

 

  

ectothermy

 

  

presence of four walking limbs

 

  

presence of teeth

 

presence of a notochord

The temperature-regulating center of vertebrate animals is located in the _____.

  

liver

 

  

hypothalamus

 

  

subcutaneous layer of the skin

 

  

thyroid gland

 

hypothalamus

Loss of water from the aerial parts of plants is called _____.

  

respiration

 

  

transpiration

 

  

dehydration

 

  

gas exchange

 

transpiration

Which of the following terms is mismatched with its meaning or characteristics?

  

Chordate: animal with notochord

\
Diploblastic: ectoderm and mesoderm

 

  

Triploblastic: ectoderm, mesoderm, and endoderm

\
  

Eumetazoa: definite symmetry; tissues organized

 

Diploblastic: ectoderm and mesoderm

If isolated plant cells with a water potential averaging -0.5 MPa are placed into a solution with a water potential of -0.3 MPa, which of the following would be the most likely outcome?

\
  

The pressure potential of the cells would increase.

 

  

Solutes would move out of the cells.

 

  

Water would move out of the cells.

 

  

The cell walls would rupture, killing the cells.

 

The pressure potential of the cells would increase.

If isolated plant cells with a water potential averaging -0.5 MPa are placed into a solution with a water potential of -0.3 MPa, which of the following would be the most likely outcome?

  

The pressure potential of the cells would increase.

 

  

Solutes would move out of the cells.

 

  

Water would move out of the cells.

 

  

The cell walls would rupture, killing the cells.

 

The pressure potential of the cells would increase.

The movement of water across biological membranes can best be predicted by _____.

  

aquaporins

 

  

level of active transport

  

water potentials

 

  

prevailing weather conditions

 

water potentials

Which of the following statements about segmentation in animals is FALSE?

 

Segmentation facilitates the specialization of function in different parts of the body.

 

  

Segmentation may be present in both protostomes and deuterostomes.

  

Segmentation is required for animal movement.

 

  

Segmented animals are triploblastic.

 

Segmentation is required for animal movement.

Genetic variation _____.

  

arises in response to changes in the environment

 

  

tends to be reduced by when diploid organisms produce gametes

 

  

is created by the direct action of natural selection

 

 

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

 

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

 

Aboveground epidermal cells secrete a waxy layer, called the _______, which helps retard water loss from stems and leaves. 

  

bark 

  

cuticle 

  

suberin 

  

lignin

cuticle 

Which of the following characteristics evolved independently in mammals and birds?

  

amniotic eggs

 

  

bone

 

  

jaws

 

  

endothermy

 

endothermy

Select the correct sequence of vertebrate development following fertilization.

 

cleavage --> gastrulation --> neurulation --> organogenesis --> neural crest formation

 

gastrulation --> cleavage --> neurulation --> neural crest formation --> organogenesis

 

gastrulation --> neurulation --> neural crest formation --> cleavage --> organogenesis

 

cleavage --> gastrulation --> neurulation --> neural crest formation --> organogenesis

cleavage --> gastrulation --> neurulation --> neural crest formation --> organogenesis

Over time, the movement of people on Earth has steadily increased. This has altered the course of human evolution by increasing _____.

  

genetic drift

  

gene flow

 

  

nonrandom mating

 

  

geographic isolation

 

gene flow

The outer-to-inner sequence of tissue layers in a post-gastrulation vertebrate embryo is _____.

  

ectoderm endoderm mesoderm

  

mesoderm endoderm ectoderm

\
  

ectoderm mesoderm endoderm

  

endoderm ectoderm mesoderm

ectoderm mesoderm endoderm

Nematodes and arthropods both _____.

\
  

grow by shedding their exoskeleton

 

  

are segmented

 

  

develop an anus from the blastopore (pore) formed in the gastrula stage

 

  

are diploblastic

 

grow by shedding their exoskeleton

 

Which of the following represents the correct chronological sequence of developmental events?

\
Thickening of neural ectoderm, movement of neural folds, formation of the neural tube

 

 

Formation of the neural tube, movement of neural folds, thickening of neural ectoderm

 

Movement of neural folds, formation of the neural tube, thickening of neural ectoderm

 

Thickening of neural ectoderm, formation of the neural tube, movement of neural folds

 

Thickening of neural ectoderm, movement of neural folds, formation of the neural tube

Which of the following is (are) problematic when the goal is to construct phylogenies that accurately reflect evolutionary history?

\
  

homoplasies

 

  

synapomorphies

 

  

monophyletic taxa

\
  

homologies

 

homoplasies

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?

  

0\.42

 

  

0\.32

 

  

0\.20

\
  

0\.81

 

0\.81

Which of the following does NOT affect the diffusion of a gas across a membrane

  

the size of the gas molecule.

 

**Correct Answer**

  

which membrane transport proteins are present.

 

  

the concentration difference of the gas on the two sides of the membrane.

 

  

the membrane surface area.

 

which membrane transport proteins are present.

The most important ion in controlling the movement of water into and out of the guard cells is

  

sodium.

 

  

potassium.

 

  

nitrogen.

 

  

carbon.

 

potassium.

How has the avian lung adapted to the metabolic demands of flight?

\
  

Gas exchange occurs during both inhalation and exhalation.

 

 

There is more dead space within the avian lung so that oxygen can be stored for future use.

  

Airflow through the avian lung is bidirectional like in mammals.

 

  

Countercurrent circulation is present in the avian lung.

 

Gas exchange occurs during both inhalation and exhalation.

Which of the following was the most serious challenge to the survival of the first land plants? 

  

a shortage of carbon dioxide 

  

desiccation 

  

animal predation 

  

not enough sunlight

desiccation 

Which tissues are INCORRECTLY matched to their progenitor germ layer? 

  

endoderm-muscles 

  

endoderm-lining of the digestive tract 

  

mesoderm-blood vessels

  

ectoderm-epidermis

endoderm-muscles 

In a developing frog embryo, most of the yolk is _____.

  

found within the cleavage furrow

  

located near the vegetal pole

 

  

distributed equally throughout the embryo

 

  

located near the animal pole

 

located near the vegetal pole

 

The last common ancestor of all animals was probably a _____.

  

multicellular fungus

 

  

unicellular chytrid

 

  

multicellular algae

 

**Correct Answer**

  

flagellated protist

 

flagellated protist

Which of the following is a protostome that does NOT shed a cuticle, i.e it is a lophotrochozoan?

  

Insects

 

  

Mollusks

 

  

Cnidarians

 

  

Sponges

 

Mollusks

In humans, identical twins are possible because _____.

  

early blastomeres can form a complete embryo if isolated

 

  

cytoplasmic determinants are distributed unevenly in unfertilized eggs

 

  

the gray crescent divides the dorsal-ventral axis into new cells

 

  

extraembryonic cells interact with the zygote nucleus

 

early blastomeres can form a complete embryo if isolated

 

Cells move to new positions as an embryo establishes its three germ-tissue layers during _____.

  

induction

\
  

gastrulation

 

  

determination

 

  

cleavage

 

gastrulation

The production of sterile mules by interbreeding between female horses (mares) and male donkeys (jacks) is an example of _____.

  

a prezygotic barrier

 

  

mechanical isolation

 

  

reduced hybrid fertility

 

  

reduced hybrid viability

 

reduced hybrid fertility

Despite their seemingly simple anatomy and radial symmetry, ______ are a type of deuterostome, and closely related to the chordates.

  

Sea Anemones and jellyfish

 

  

Flatworms and mollusks

 

  

Jellyfish and squid

\
  

Sea urchins and starfish

 

Sea urchins and starfish

Action potentials move along axons _____.

 

by activating the sodium-potassium "pump" at each point along the axonal membrane

  

by reversing the concentration gradients for sodium and potassium ions

 

  

more rapidly in myelinated than in non-myelinated axons

 

  

more slowly in axons of large than in small diameter

 

more rapidly in myelinated than in non-myelinated axons

Penguins, seals, and tuna have body forms that permit rapid swimming, because _____.

 

the shape is a convergent evolutionary solution, which reduces drag while swimming

 

 

this is the only shape that will allow them to maintain a constant body temperature in water

 

all of their bodies have been compressed since birth by intensive underwater pressures

 

  

all share a recent common ancestor

 

the shape is a convergent evolutionary solution, which reduces drag while swimming

The force driving simple diffusion is _____, while the energy source for active transport is _____.

  

transmembrane pumps; electron transport

 

  

phosphorylated protein carriers; ATP

 

  

the concentration gradient; ATP

 

  

the concentration gradient; ADP

 

the concentration gradient; ATP

The "threshold" potential of a membrane is the _____. 

  

lowest frequency of action potentials a neuron can produce 

  

minimum hyperpolarization needed to prevent the occurrence of action potentials 

  

peak amount of depolarization seen in an action potential 

  

minimum depolarization needed to operate the voltage-gated sodium channel 

\

minimum depolarization needed to operate the voltage-gated sodium channel

Carbon dioxide levels in the blood and cerebrospinal fluid affect pH. This enables the organism to sense a disturbance in gas levels as _____.

 

the brain directly measures and monitors oxygen levels and causes breathing changes accordingly

 

stretch receptors in the lungs cause the medulla oblongata to speed up or slow breathing

 

the medulla oblongata, which is in contact with cerebrospinal fluid, monitors pH and uses this measure to control breathing

 

the brain alters the pH of the cerebrospinal fluid to force the animal to retain more or less carbon dioxide

the medulla oblongata, which is in contact with cerebrospinal fluid, monitors pH and uses this measure to control breathing

The common edible frog of Europe is a hybrid between two species, Rana lessonae and Rana ridibunda. The hybrids were first described in 1758 and have a wide distribution, from France across central Europe to Russia. Both male and female hybrids exist, but when they mate among themselves, they are rarely successful in producing offspring. What can you infer from this information?

  

Postzygotic isolation exists between the two frog species.

 

  

Prezygotic isolation exists between the two frog species.

 

  

The hybrids form a separate species under the biological species concept.

 

  

These two species are likely in the process of fusing back into one species.

 

Postzygotic isolation exists between the two frog species.

 

Acetylcholine released into the junction between a motor neuron and a skeletal muscle binds to a sodium channel and opens it. This is an example of _____.

  

a second-messenger-gated sodium channel

 

  

a chemical that inhibits action potentials

 

  

a ligand-gated sodium channel

 

  

a voltage-gated potassium channel

 

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a ligand-gated sodium channel

Which of the following is (are) unique to animals?

  

heterotrophy

 

  

the structural carbohydrate, chitin

 

  

meiosis for forming gametes

 

  

nervous system signal conduction and muscular movement

 

\

nervous system signal conduction and muscular movement

 

Arrange in the correct sequence these components of the mammalian immune system as it first responds to a pathogen. \n I. Pathogen is destroyed. \n II. Lymphocytes secrete antibodies. \n III. Antigenic determinants from pathogen bind to antigen receptors on lymphocytes. \n IV. Lymphocytes specific to antigenic determinants from pathogen become numerous. \n V Only memory cells remain. 

  

III --> IV --> II --> I --> V 

  

IV --> II --> III --> I --> V 

  

II --> I --> IV --> III --> V 

  

I --> III --> II --> IV --> V 

\

III --> IV --> II --> I --> V