BIO 360 Exam 1

Which domain of intracellular receptors binds to responsive elements in the nucleus? A) DNA-binding domain B) transactivation domain C) ligand-binding domain D) membrane-binding domain

A) DNA-binding domain

Why is ATP a physiologically important molecule? A) It links major pathways that release energy with those that require energy. B) It is an energy source that is found in high concentrations in cells. C) It is an energy source that is always available in large quantities. D) All of these are correct

A) It links major pathways that release energy with those that require energy.

Which of the following statements is correct? A) Ligand-gated ion channels change the ion permeability of the membrane, which results in a response by the target cell. B) Intracellular receptors interact with hydrophilic chemical messengers. C) Receptor enzymes activate extracellular enzymes. D) G protein-coupled receptors interact with hydrophobic chemical messengers.

A) Ligand-gated ion channels change the ion permeability of the membrane, which results in a response by the target cell.

When maintaining homeostasis, it is important to do all of the following EXCEPT A) control external conditions. B) protect vital areas from damaging changes. C) generate compensatory responses to the changes. D) detect external conditions.

A) control external conditions.

Movement of Na+ through its channels is primarily responsible for the __________ of an action potential. A) depolarization phase B) repolarization phase C) hyperpolarization phase D) after-hyperpolarization phase

A) depolarization phase

In early gastrulation, a depression called a blastopore forms. If this blastopore forms the anus, the animals are referred to as A) deuterostomes. B) protostomes. C) gastrostomes. D) diploblasts.

A) deuterostomes.

It is possible for cells to communicate directly (via a connection of the cytoplasm) with each other by using A) gap junctions. B) paracrine signaling. C) endocrine signaling. D) autocrine signaling.

A) gap junctions.

The flippers of marine mammals, the legs of dogs, and the wings of birds are examples of ______________ structures. A) homologous B) analogous C) convergent D) shared

A) homologous

Animal physiology is the study of: A) how structures allow animals to function. B) the chemical reactions found in animals. C) the genetic lineage seen in the evolution of animals. D) migratory patterns of animals.

A) how structures allow animals to function.

Myelination increases the speed of conduction by decreasing the time constant and increasing the length constant. It achieves this by A) increasing membrane resistance and decreasing capacitance. B) increasing both membrane resistance and capacitance. C) decreasing membrane resistance and increasing capacitance. D)decreasing both membrane resistance and capacitance.

A) increasing membrane resistance and decreasing capacitance.

Given the information below, the neuron with the characteristics listed in choice __________ would have the fastest conduction velocity. A) myelinated, 50 μm diameter B) myelinated, 10 μm diameter C) unmyelinated, 50 μm diameter D) unmyelinated, 10 μm diameter

A) myelinated, 50 μm diameter

The scaling coefficient for metabolic rate should be 2/3 is based on A) relationships between surface area and volume. B) relationships between body mass and volume. C) relationships between volume and metabolism. D) relationships between metabolism and activity of the animal.

A) relationships between surface area and volume.

A chemical is termed a neurohormone when it is A) released by a neuron, but travels in the blood like a hormone. B) released by an endocrine gland, but binds to receptors on a neuron. C) released by neurons and endocrine glands. D) known to be involved with communication, but scientists have not concluded which system uses it.

A) released by a neuron, but travels in the blood like a hormone.

Up-regulation of receptors A) results in increased sensitivity to its ligand. B) results in decreased sensitivity to its ligand. C) occurs when a ligand has been present at high levels. D) both B and C

A) results in increased sensitivity to its ligand.

The correct term(s) for the most abundant liquid in which other molecules are dissolved is/are A) solvent B) solute. C) solution. D) both A and C

A) solvent

If multicellular organisms have distinct cell types, this means that A) the different cell types express different genes. B) some of the organism's cells will grow larger over time. C) every cell will be different. D) some cells will have cell walls and others won't.

A) the different cell types express different genes.

Ion channels that open or close based on changes in the membrane potential are called A) voltage-gated channels. B) ligand-gated channels. C) mechanogated channels. D) porins.

A) voltage-gated channels.

Which of the following statements is true about phenotype? A) Phenotype is affected by organization at the biochemical level only. B) Altering phenotype allows an organism to change its physiological response. C) After an initial development period, phenotype of an organism is static. D) Genotype may influence phenotype, but phenotype never affects genotype.

B) Altering phenotype allows an organism to change its physiological response.

_________ is the metabolic pathway that synthesizes glycogen. A) Gluconeogenesis B) Glycogenesis C) Glycogenolysis D) Glycolysis

B) Glycogenesis

Which of the following statements is true for a strong base? A) It dissociates slowly. B) It has a high pK. C) It easily donates [H+].

B) It has a high pK.

Why do steroids take so long to generate change when they bind to intracellular receptors? A) The steroid receptor complex must then exit the cell to exert its effects. B) The bound receptors affect gene transcription rates. C) The intracellular receptors have very slow kinetics.

B) The bound receptors affect gene transcription rates.

Which of the following choices is not a basic feature of cellular communication? A) The signal must be produced. B) The signal can be produced only by a eukaryote. C) The signal must be transported to a target cell. D) The target cell must respond to the signal.

B) The signal can be produced only by a eukaryote.

Which of the following statements is true of graded potentials? A) They travel over long distances. B) They have different amplitudes. C) They are typically found in axons. D) They travel without decrement.

B) They have different amplitudes.

Which of the following graded potentials will be most likely to generate an action potential? A) a subthreshold potential B) a suprathreshold potential C) a hyperpolarizing potential D) an inhibitory potential

B) a suprathreshold potential

Conduction of action potentials along an axon is termed saltatory conduction because the action potential A) is dependent on the ions Na+ and K+, portions of salts. B) appears to leap or jump from node to node. C) is named after Johan Saltare, who first discovered it. D) moves very rapidly down the axon.

B) appears to leap or jump from node to node.

All animals A) eat other animals. B) are multicellular. C) reproduce sexually. D) are triploblastic.

B) are multicellular.

Free energy (ΔG) represents the amount of energy A) required to start the reaction. B) available for use from a reaction. C) that could potentially be released from a reaction. D) lost as heat during the reaction.

B) available for use from a reaction.

When indirect signaling is used, the target cell responds to the signal when that chemical A) binds to an enzyme. B) binds to a receptor. C) binds to a gene. D) binds to the nuclear membrane.

B) binds to a receptor.

You learned that form reflects function. You know that fibrous plant materials are harder to digest than animal-based proteins. When comparing the digestive systems of carnivores and herbivores, you expect that A) carnivores have much larger stomachs than herbivores B) carnivores have a much shorter intestinal tract than herbivores C) carnivores have a larger intestinal tract than herbivores D) the digestive systems of the two are similar because both are mammals

B) carnivores have a much shorter intestinal tract than herbivores

Collagen is best described as a(n) A) intracellular matrix protein. B) extracellular matrix protein and one of the earliest innovations observed in animals. C) matrix protein that all animals have, with the exception of sponges. D) intracellular matrix that is a basis for communication between cells

B) extracellular matrix protein and one of the earliest innovations observed in animals.

Tropic or trophic hormones A) are found in tropical organisms. B) have the ability to cause other hormones to be released. C) are secreted only from the hypothalamus. D) both B and C

B) have the ability to cause other hormones to be released.

The proximate cause of an organism's unique characteristic can be answered by A) looking for evolutionary advantages of the characteristic. B) identifying the genes that regulate the characteristic. C) studying the animals lineage.

B) identifying the genes that regulate the characteristic.

Diffusion of a solute through a solution is decreased by an A) increased concentration gradient. B) increased size of molecule. C) increased diffusion coefficient. D) increased diffusion area.

B) increased size of molecule.

The vertebrate hormones involved in water and electrolyte balance in the body are called A)ecdysteroids. B) mineralocorticoids. C) glucocorticoids. D) reproductive hormones.

B) mineralocorticoids.

One theme in physiology states that the physiology of an animal is part of its __________, which is based on its __________ and environmental influences. A) genotype; ancestry B) phenotype; genotype C) ancestry; phenotype D) phenotype; diet

B) phenotype; genotype

Km in the Michaelis-Menten equation represents A) the maximum amount of substrate that can be catalyzed by the enzyme. B) the amount of substrate required for the initial velocity to be half of the maximal velocity. C) the amount of substrate required to start an enzymatic reaction. D) a set constant used for all enzymatic reactions.

B) the amount of substrate required for the initial velocity to be half of the maximal velocity.

The squid served as an ideal model system to study neurophysiology because A) squids are invertebrates and invertebrates have a simpler nervous system than vertebrates. B) the large diameter of the squid's neurons enabled researchers to make recordings from inside of a nerve cell. C) fast electrical communication is a unique feature of squids. D) squids are active predators and therefore have many nerves that can be easily studied.

B) the large diameter of the squid's neurons enabled researchers to make recordings from inside of a nerve cell.

The main reason the interior of the cell is negative at rest is because A) the membrane is more permeable to Na+ than any other ion. B) the membrane is more permeable to K+ than any other ion. C) the Na+/K+ pump is electrogenic. D) it contains a much higher concentration of Cl-.

B) the membrane is more permeable to K+ than any other ion.

Which of the following statements is true of any communication system? A) Neurons are always involved. B) The endocrine system is always involved. C) A signal must always be sent and received. D) Signals can be sent only in electrical form.

C) A signal must always be sent and received.

How can environmental conditions such as salt concentration, temperature, and pH physically affect the enzyme itself? A) Ions can bind to the active sites of enzymes, preventing the binding of substrate. B) Changes in temperature change the rate at which molecules interact with the enzyme. C) All these factors can disrupt the weak bonds that hold the enzyme in its active conformation. D) These factors affect only the substrate.

C) All these factors can disrupt the weak bonds that hold the enzyme in its active conformation.

Which of the following statements is true about phenotype? A) After an initial development period, phenotype of an organism is static. B) Phenotype is affected by organization at the biochemical level only. C) Altering phenotype allows an organism to change its physiological response. D) Genotype may influence phenotype, but phenotype never affects genotype.

C) Altering phenotype allows an organism to change its physiological response.

Which of the following statements is true concerning secondary active transporters? A) A symporter can bind only one particle. B) An exchanger/antiporter will always be electroneutral. C) Electrogenic carriers generate a charge difference across the membrane. D) The direction in which charged particles are transported across the membrane does not affect the electrical gradient.

C) Electrogenic carriers generate a charge difference across the membrane.

What is the advantage of storing energy as glycogen rather than as lipids? A) It contains more energy per unit mass. B) It does not prevent physical functions of a cell. C) It can be mobilized very rapidly. D) both A and B

C) It can be mobilized very rapidly.

The G-protein-coupled receptors are a diverse family with this common feature. A) They are activated when a kinase molecule phosphorylates them. B) They are activated when GTP is released from the G protein. C) They are activated when GTP binds to the G protein. D) They are activated when the α subunit binds to the β and γ subunits.

C) They are activated when GTP binds to the G protein.

The signal transduction cascade acts as the __________ of a transducer. A) receiver B) transducer C) amplifier D) responder

C) amplifier

Metabolic pathways that include synthetic reactions are called all of the following, except A) anabolic B) amphibolic C) catabolic

C) catabolic

The term adaptation most commonly refers to A) changes within an individual that are irreversible. B) changes within an individual that are reversible. C) changes within a population seen over time. D) changes within an individual that cannot be inherited.

C) changes within a population seen over time.

Which of the following types of energy is strictly potential energy? A) mechanical energy B) radiant energy C) chemical energy D) electrical energy

C) chemical energy

The first animals to show true tissues were A) sponges. B) placozoans. C) cnidarians. D) ctenophores.

C) cnidarians.

Amphibians differ from other tetrapods in that amphibians A) are much smaller. B) have a more rigid spinal column. C) depend on water for reproduction. D) A and C

C) depend on water for reproduction

One approach, known as __________, says that we can learn about one level of organization by studying the functions at the level below it. A) systematics B) bioinformatics C) eductionism D) emergence

C) eductionism

The response of a cell to a particular chemical messenger is determined by the A) ligand-binding domain. B) transmembrane domain. C) functional domains. D) chemical messenger itself.

C) functional domains.

Which of the following carbohydrates is a monosaccharide? A) sucrose B) lactose C) glucose D) maltose

C) glucose

All of the following are lipids, EXCEPT A) phospholipids. B) steroids. C) glycogen. D) triglycerides.

C) glycogen.

A receptor that binds to a ligand at very low concentrations has a A) high dissociation constant. B) low Ka. C) high affinity for the ligand. D) low affinity for the ligand.

C) high affinity for the ligand.

The portion of the transmembrane receptor that binds to hydrophilic messengers is termed the A) receptor-binding domain. B) transmembrane domain. C) ligand-binding domain. D) intracellular domain.

C) ligand-binding domain.

Which of the following animals are amniotes? A) amphibians, mammals, birds, and reptiles B) amphibians, birds, and reptiles C) mammals, birds, and reptiles D) birds and reptiles

C) mammals, birds, and reptiles

One of the biggest challenges facing terrestrial organisms is to A) escape from predators. B) survive food shortages. C) reduce water loss. D) find shelter.

C) reduce water loss.

All the choices below are examples of glial cells, but which one is NOT associated with the central nervous system? A) microglia B) astrocytes C) schwann cells D) oligodendrocytes

C) schwann cells

Axons are found in the __________ region of a neuron. A) signal reception B) signal integration C) signal conduction D) signal transmission

C) signal conduction

Surface area to volume ratio influences thermal physiology such that A) small animals have a higher surface area to volume ratio, decreasing heat loss. B) small animals have a lower surface area to volume ratio, decreasing heat loss. C) small animals have a higher surface area to volume ratio, increasing heat loss. D) small animals have a lower surface area to volume ratio, increasing heat loss.

C) small animals have a higher surface area to volume ratio, increasing heat loss.

In a neuromuscular junction, the muscle is the A) presynaptic cell. B) postsynaptic cell. C) synaptic cell. D) synapse.

C) synaptic cell.

When two or more hormones are __________, then the response of all the hormones when applied at the same time is greater than the sum of the responses to each hormone applied individually. A) antagonistic B) additive C) synergistic D) agonistic

C) synergistic

Neural signaling is different from other types of long-distance signaling because A) it involves the release of chemical signals. B) it involves the use of receptors. C) the signal is contained within a single cell as it travels the long distance. D) it relies on the blood to carry the signal from one cell to the next.

C) the signal is contained within a single cell as it travels the long distance.

__________ is a generalized carrier protein that plays a major role in vertebrate blood. A) Hemoglobin B) Globulin C) Cholesterol D) Albumin

D) Albumin

Which of the following statements provides inaccurate information? A) In paracrine communication, the target cell receives chemical messenger from signal cell via diffusion. B) A neurotransmitter is a chemical messenger that had been converted from an electrical signal. C) Endocrine messengers are hormones. D) Allelochemicals are chemical messengers released into the external environment by individuals of the opposite sex but of the same species

D) Allelochemicals are chemical messengers released into the external environment by individuals of the opposite sex but of the same species

Which of the following is a true difference between electrical and chemical synapses? A) Electrical synapses are found in the central nervous system. B) Electrical synapses are the most common type of synapse. C) Electrical synapses typically send information in one direction (presynaptic cell to postsynaptic cell). D) Electrical synapses are much faster

D) Electrical synapses are much faster

Of those listed here, which of the following characteristics would be most beneficial for animals to successfully survive on land? A) The presence of a notocord and dorsal nerve cord. B) The ability to undergo metamorphosis. C) The presence of an open circulatory system. D) The presence of an exoskeleton.

D) The presence of an exoskeleton.

Which of the following characteristics apply to all protists? A) They are animal-like. B) They have a cell wall. C) They can photosynthesize. D) They have a nucleus.

D) They have a nucleus.

pH is a measure of A) ratio of [OH-] to [H+]. B) [OH-]. C) ratio of [H+] to [OH-]. D) [H+].

D) [H+]

Adaptation can change the genetic composition of a population because A) environmental stressors favor survival of certain genotypes. B) individuals possessing favorable genes tend to produce more offspring. C) genes are passed on only if offspring are produced. D) all of the above

D) all of the above

Exocrine secretions are used to communicate between different animals and A) to digest foodstuffs. B) to aid in locomotion. C) in trapping prey. D) all of the above

D) all of the above

Maintaining homeostasis relies on A) short-term behavioral changes. B) short-term physiological changes. C) long term strategies. D) all of the above

D) all of the above

Neurons are capable of detecting and transducing incoming signals such as A) light. B) pressure. C) environmental chemicals. D) all of the above

D) all of the above

Neurotransmitters are composed of a variety of different chemicals, including A) amino acids. B) neuropeptides. C) biogenic amines. D) all of the above

D) all of the above

Only certain organisms possess gene variants that are able to exchange Na+ for K+, thus making the Na+/K+ ATPase unique to: A) fungi and plants. B) fungi. C) plants and animals. D) animals.

D) animals.

Antagonists are compounds that A) prevent synthesis of new receptors. B) prevent synthesis of hormones. C) bind to a receptor, activating it. D) bind to a receptor, but do not activate it.

D) bind to a receptor, but do not activate it.

Glycolysis is an important metabolic pathway for the production of ATP because A) it can proceed with or without oxygen. B) it can produce ATP quickly. C) it can be used to metabolize fats and carbohydrates equally well. D) both A and B

D) both A and B

Organisms that are closely related to each other will A) share some features with all other organisms. B) share some features only with organisms from this same group. C) have no features in common with any other organism. D) both A and B

D) both A and B

In a __________ feedback loop, both the endocrine and nervous systems can be involved. A) first order B) second order C) third order D) both B and C

D) both B and C

What role does Ca2+ play in synaptic transmission? A) Ca2+ is released into the synapse, transmitting a signal to the postsynaptic cell. B) Ca2+ causes the release of vesicles from the readily releasable pool. C) Ca2+ causes vesicles to move from the storage pool to docking proteins. D) both B and C

D) both B and C

When an ion crosses the membrane and binds to a protein to accomplish this feat, it is using A) passive diffusion. B) facilitated diffusion. C) active transport. D) either B or C

D) either B or C

When chemical signals are sent between two animals, __________ communication is being used. A) neural B) endocrine C) autocrine D) exocrine

D) exocrine

In the thyroid hormones, T3 and T4, the 3 and 4 refer to the A) relative half-life (3 or 4 hours). B) number of enzymes required to synthesize the hormone. C) number of tyrosine molecules linked together. D) number of iodines which are found on the hormone

D) number of iodines which are found on the hormone

Action potentials appear to travel over long distances without decaying because A) the axons are perfectly insulated, so no current is able to leak out. B) the action potential uses completely different ions than graded potentials. C) once the electrical signal has passed threshold, it is impossible for the signal to decay. D) one action potential generates the next one in an adjacent area of membrane.

D) one action potential generates the next one in an adjacent area of membrane.

Peptide hormones (chains of 50 or fewer amino acids) are first synthesized as A) the hormone itself. B) prehormones. C) prohormones. D) preprohormones.

D) preprohormones.

The __________ structure of proteins involves interactions of amino acids that are found on different subunits. A) primary B) secondary C) tertiary D) quaternary

D) quaternary

One key advantage associated with bilateral symmetry in animals is A) an increase in speed. B) the presence of a coelom. C) the evolution of limbs. D) the evolution of cephalization.

D) the evolution of cephalization

Gap junctions are formed by A) groups of 8-12 connexons making a pore in one cell. B) groups of 4-6 innexins or connexins forming a pore in one cell. C) connexons from adjacent cells connecting with each other to form a cytoplasmic bridge. D) both A and C E) both B and C

E) both B and C