In mammals, most gas exchange between the atmosphere and blood occurs in?

1. bronchi
2. larynx
3. trachea
4. alveoli

D

The exhalation of air from human lungs is caused by?

1. a decrease in the volume of the thoracic cavity
2. the contraction of the diaphragm
3. the closure of the epiglottis
4. the expansion of the rib cage

A

Which of the following can be pathogens?

1. A virus
2. Bacteria
3. All of these can be pathogens
4. Fungus

C

Damage to the sinoatrial node in humans:

1. would disrupt the rate and timing of cardiac muscle contractions
2. would have a negative effect on capillary control
3. would have a direct effect on blood pressure
4. would block electrical signals between the bundle branches and the Purkinje fibers

A

The epiglottis of a human covers the glottis when he or she is:

1. sleeping
2. breathing
3. talking
4. swallowing

D

Based on your understanding of lung function which of the following types of epithelium are used to line the lungs?

1. stratified squamous epithelium
2. simple cuboidal epithelium
3. simple squamous epithelium
4. stratified columnar epithelium

C

If you gently twist your earlobe, it does not remain distorted because it contains:

1. adipose tissue
2. loose connective tissue
3. reticular fibers
4. elastin fibers

D

Hypoglycemia, or low levels of glucose in the blood of a healthy human, is "corrected" by:

1. increased insulin levels
2. increased blood filtration
3. increased insulin and glucagon
4. increased glucagon levels

D

What type of animal is most likely to have a large cecum?

1. herbivores
2. carnivores
3. omnivores
4. animals with a strong immune system

A

T cells undergo maturation in the ________ gland?

1. thyroid
2. thymus
3. pituitary
4. adrenal

B

What is an epitope?

1. that part of an antigen that actually binds to an antigen receptor
2. part of the interferons that penetrate foreign cells
3. two structurally similar antibodies dissolved in the blood plasma
4. a protein protruding from the surface of B cells

A

What is one characteristic all muscle types share?

1. presence of actin and myosin
2. cells that lengthen when appropriately stimulated
3. striated banding patterns seen under the microscope
4. a response that can be consciously controlled

A

To maintain adequate nutrition, animals require dietary access to certain amino acids. An amino acid that is referred to as "nonessential" would be best described as one that:

1. must be ingested in the diet
2. can be made by the animal's body from other substances
3. is not found in many proteins
4. is not readily absorbed by the gastrointestinal tract

B

What type of pathogen is multicellular and steals energy from its host?

1. All of these
2. Bacteria
3. Parasite
4. Virus

C

Which of the following is an example of connective tissue?

1. smooth muscle
2. blood
3. cuboidal epithelium
4. outer skin

B

Where are most nutrients absorbed from food?

1. liver
2. small intestine
3. stomach
4. mouth

B

When you hold your breath, which of the following blood gas changes first leads to the urge to breathe?

1. falling CO2
2. falling O2
3. rising O2
4. rising CO2

D

What is the purpose of the epiglottis?

1. it seals the digestive tract to prevent air from entering the stomach
2. it secretes digestive enzymes
3. it pushes the bolus down the throat
4. it prevents swallowed food from entering the lungs

D

Which of the following is a function of antibodies?

1. injecting toxins into living pathogens
2. none of these
3. secreting cytokines that attack macrophages to infection sites
4. acting as a barrier for pathogens

B

You are studying a large tropical reptile that has a high and relatively stable body temperature. How would you determine whether this animal is an endotherm or an ectotherm?

1. You measure the metabolic rate of the reptile, and because it is higher than that of a related species that lives in temperate forests, you conclude that this reptile is an endotherm and its relative is an ectotherm.
2. You know from its high body temperature that it must be an endotherm
3. You know that it is an ectotherm because it is not a bird or mammal
4. You subject this reptile to various temperatures in the lab and find that its body temperature and metabolic rate change with the ambient temperature. You conclude that it is an ectotherm.

D

Cardiac muscle cells are both:

1. smooth and under voluntary control
2. smooth and under involuntary control
3. striated and interconnected by intercalated disks
4. striated and under voluntary control

C

The panting responses that are observed in overheated birds and mammals dissipates excess heat by:

1. countercurrent exchange
2. estivation
3. evaporation
4. vascoconstriction

C

Which of the following is an inflammation-causing signal released by mast cells at the site of an infection?

1. histamine
2. interferon
3. mucus
4. antigen

A

Why are cells organized into tissues?

1. tissues keep cells connected tightly together
2. all of the
3. it helps cells work together and makes them easier to control
4. cells cannot receive energy unless they are in a tissue

C

A drought in the desert reduces food availability for several months. A lizard (an ectotherm) survives until food availability increases but a desert mouse (an endotherm) does not. Why is this?

1. ectotherms have more efficient muscles for catching prey
2. endotherms cannot dissipate heat from their body
3. ectotherms require much less energy to function
4. endotherms require energy for constant growth

C

A vaccine is usually composed of:

1. inactivated disease-causing microbes
2. antibodies that recognize invading microbes
3. macrophages that fight infection
4. a hormone that boosts immunity

A

Muscles are joined to bones by:

1. ligaments
2. cartilage
3. tendons
4. loose connective tissue

C

The nourishment, insulation, and support for neurons is the result of activity by:

1. smooth muscle
2. intercalated disks
3. fibroblasts
4. glial cells

D

What cell type stimulates both the humoral and cell-mediated immune pathways?

1. macrophages
2. helper T cells
3. cytotoxic T cells
4. natural killer cells

B

What is the purpose of villi and microvilli in the small intestine?

1. secretes digestive enzymes
2. push food through intestine
3. absorb water
4. increase surface area

D

Which of the following best defines an antigen?

1. proteins embedded in B cell membranes
2. foreign molecules that trigger the generation of antibodies
3. signaling proteins released during an inflammatory response
4. proteins found in the blood that cause foreign blood cells to clump

B

The set of blood vessels with the lowest blood pressure driving flow is:

1. the veins
2. the bronchioles
3. the arteries
4. the arterioles

A

Salivary amylase digests:

1. starches
2. proteins
3. DNA
4. lipids

A

Which of the following are true of bile?

1. it is stored in the gallbladder
2. it breaks up fat globs
3. all of these
4. it is created in the liver

C

Hibernation during seasons of environmental stress is an example of:

1. shivering thermogenesis
2. endothermy
3. evaporative cooling
4. torpor

D

Which nitrogenous waste requires hardly any water for its excretion?

1. nitrogen gas
2. uric acid
3. urea
4. ammonia

B

Saltatory ('leaping') conduction is a term applied to:

1. jumping from one neuron to an adjacent neuron
2. jumping from one node of Ranvier to the next in a myelinated neuron
3. conduction of impulses across electrical synapses
4. rapid movement of an action potential reverberating back and forth along a neuron

B

after eating a carbohydrate-rich meal that spikes blood sugar, the mammalian pancreas increases its secretion of:

1. insulin
2. oxytocin
3. glucagon
4. thyroxine

A

The osmoregulatory process called secretion refers to:

1. filtration
2. formation of filtrate at an excretory structure
3. formation of an osmotic gradient along an excretory structure
4. selective elimination of excess ions and toxins from body fluids

D

The point of connection between two communicating neurons if called:

1. the synapse
2. the cell body
3. the glia
4. the dendrite

A

Imagine you are resting comfortably on a sofa after dinner. This could be described as a state with:

1. increased activity in the sympathetic, parasympathetic, and enteric nervous systems
2. decreased activity in the sympathetic nervous system, and increased activity in the parasympathetic and enteric nervous systems
3. decreased activity in the sympathetic, parasympathetic, and enteric nervous systems
4. increased activity in the sympathetic nervous system, decreased activity in the parasympathetic nervous system, and increased activity in the enteric nervous system

B

The increased contraction of the human uterus during labor and delivery is at least partially due to the actions of:

1. thyroxine
2. oxytocin
3. growth hormone
4. glucagon

B

From earliest to latest, the overall sequence of early development proceeds in which of the following sequences?

1. gastrulation -> organogenesis -> cleavage
2. cleavage -> gastrulation -> organogenesis
3. ovulation -> gastrulation -> fertilization
4. gastrulation -> blastulation -> neurulation

B

The archenteron (an internal tube) in the developing frog eventually develops into the:

1. blastocoel
2. digestive tract
3. brain and spinal cord
4. heart and lungs

B

The threshold potential of a membrane:

1. is the lowest frequency of action potentials a neuron can produce
2. is the minimum depolarization needed to operate the voltage-gated sodium and potassium channels
3. is the peak amount of depolarization seen in an action potential
4. is the minimum hyper-polarization needed to prevent the occurrence of action potentials

B

For a neuron at a resting potential of -70 mV, an increase in the movement of potassium ions out of that neuron's cytoplasm would result in:

1. the depolarization of the neuron
2. the hyperpolarization of the neuron
3. the replacement of potassium ions with sodium ions
4. the neuron switching on its sodium-potassium pump to restore the initial conditions

B

In humans, the follicular cells that remain behind in the ovary following ovulation become:

1. swept into the fallopian tube
2. the placenta, which secretes cervical mucus
3. a steroid-hormone synthesizing structure called the corpus luteum
4. the ovarian endometrium that is shed during menstruation

C

Among these choices, the most energetically efficient locomotion per unit mass is likely:

1. running by a 50-gram rodent
2. swimming by a 100-kg tuna (bony fish)
3. swimming by a 10-g minnow (bony fish)
4. running by a 40-kg ungulate

B

Fertilization of human eggs usually takes place in the:

1. oviduct
2. ovary
3. vagina
4. uterus

A

In the human retina:

1. cone cells can detect color, but rod cells cannot
2. cone cells, but not rod cells, have a visual pigment
3. cone cells are more sensitive than rod cells to light
4. rod cells are most highly concentrated in the center of the retina

A

The perceived pitch of a sound depends on:

1. which part of the tympanic membrane is being vibrated by sound waves
2. whether or not the sound moves the incus, malleus, and stapes
3. which part of the oval window produces waves in the cochlear fluid
4. which region of the basilar membrane was set in motion

D

In vertebrate animals, spermatogenesis and oogenesis differ in that:

1. spermatogenesis is not completed until after fertilization occurs, but oogenesis is complete by the time a girl is born
2. oogenesis begins at the onset of sexual maturity, whereas spermatogenesis begins during embryonic development
3. oogenesis produces four haploid cells, whereas spermatogenesis produces only one functional spermatozoon
4. cytokinesis is unequal in oogenesis, whereas it is equal in spermatogenesis

D

From earliest to latest, the overall sequence of early development proceeds in which of the following sequences?

1. acrosomal reaction -> cortical reaction -> synthesis of embryo's DNA begins -> first cell division
2. first cell division -> synthesis of embryo's DNA begings -> acrosomal reaction -> cortical reaction
3. first cell divison -> synthesis of embryo's DNA begins -> acrosomal reaction -> cortical reaction
4. cortical reaction -> acrosomal reaction -> first cell division -> synthesis of embryo's DNA begins

A

Materials are returned to the blood from filtrate by which of the following processes?

1. selective re-absorption
2. ultrafiltration
3. secretion
4. filtration

A

The embryonic precursor to the human spinal cord is the:

1. notochord
2. neural tube
3. set of bilateral somites
4. archenteron

B

The formation of the fertilization membrane requires an increase in the availability of:

1. sodium ions
2. bicarbonate ions
3. calcium ions
4. potassium ions

C

Testosterone is an example of a chemical signal that affects the very cells that synthesize it, the neighboring cells in the testis, along with distant cells outside the gonads. Thus, testosterone is an example of:

1. an endocrine signal
2. an autocrine signal, a paracrine signal, and an endocrine signal
3. an autocrine signal
4. both an autocrine signal and a paracrine signal

B

The human knee-jerk reflex requires an intact:

1. hypothalamus
2. cerebellum
3. corpus callosum
4. spinal cord

D

Myelinated neurons are especially abundant in the:

1. all areas of the brain and spinal cord
2. gray matter of the brain and gray matter of the spinal cord
3. white matter of the brain and the gray matter of the spinal cord
4. white matter in the brain and the white matter in the spinal cord

D

Neurotransmitters categorized as inhibitory are expected to:

1. close potassium channels
2. open sodium channels
3. hyperpolarize the membrane
4. close chloride channels

C

The hypothalamus:

1. functions only in neuronal transmission
2. routes sensory information to the correct brain region
3. functions only as an endocrine target, having lots of receptors on its cells
4. includes neurosecretory cells that terminate in the posterior pituitary

D

Fertilization normally:

1. merges two diploid cells into one haploid cell
2. is required for parthenogenesis
3. follows gastrulation
4. reinstates diploidy

D

A skeletal muscle deprived of adequate ATP supplies will:

1. immediately relax
2. release all actin-myosin bonds
3. fire many more action potentials than usual and enter a state of 'rigor'
4. enter a state where actin and myosin are unable to separate

D

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

1. ectoderm -> endoderm -> mesoderm
2. mesoderm -> endoderm -> ectoderm
3. ectoderm -> mesoderm -> endoderm
4. endoderm -> ectoderm -> mesoderm

C

Which nitrogenous waste requires the most energy to produce?

1. ammonia
2. uric acid
3. ammonium
4. urea

B

The somatic nervous system can alter the activities of its targets, the skeletal muscle fibers, because:

1. its signals reach the muscles via the blood
2. its light pulses activate contraction in the muscles
3. it is electrically coupled by gap junctions to the muscles
4. its signals bind to the receptor proteins on the muscles

D

A skeletal muscle with abnormally low levels of calcium ions would be impaired in:

1. initiating contraction
2. the initiation of an action potential
3. ATP hydrolysis
4. maintaining its resting membrane potential

A

When several EPSPs arrive simultaneously from differ dendritic locations, depolarizing the postsynaptic cell threshold, this is an example of:

1. spatial summation
2. temporal summation
3. an action potential with an abnormally high peak of depolarization
4. the refractory state

A

Neural transmission across a mammalian synaptic gap is accomplished by:

1. impulses ricocheting back and forth across the gap
2. impulses traveling as electrical currents across the gap
3. impulses causing the release of a chemical signal and its diffusion across the gap
4. the movement of sodium and potassium ions from the pre-synaptic neuron into the post-synaptic neuron

C

Calcium ions initiate sliding of filaments in skeletal muscles by:

1. breaking the actin-myosin cross-bridges
2. transmitting action potentials across the neuromusclar junction
3. reestablishing the resting membrane potential following an action potential
4. binding to the troponin complex which then relocates tropomyosin

D

If a ray-finned fish is to both hover (remain stationary) in the water column and ventilate its gills effectively, then what other structure besides its swim bladder will it use?

1. its lateral line system
2. its caudal (tail) fin
3. its opercula
4. its pectoral fins

C

What distinguishes complete metamorphosis from incomplete metamorphosis in insects?

1. all of these
2. the radically different appearance between adults and earlier life stages
3. the presence of sex organs in the adult, but not in earlier life stages
4. the presence of wings in the adult but not in earlier life stages

B

While sampling marine plankton in a lab, a student encounters large numbers of fertilized eggs. The student rears some of the eggs in the laboratory for further study and finds that the blastopore becomes the mouth. The embryo develops into a trochopohore larva and eventually has a true coelom. These eggs probably belonged too:

1. a mollusk
2. an echinoderm
3. an arthropod
4. a chordate

A

A brachiopod can be distinguished from a bivalve by the presence of:

1. suspension feeding
2. a lophophore
3. a digestive system with separate mouth and anus
4. two hinged shells

B

Planarians lack dedicated respiratory and circulatory systems because:

1. their flame bulbs can carry out respiratory and circulatory functions
2. they lack mesoderm as embryos and, therefore, lack the adult tissues derived from mesoderm
3. their body cavity, a pseudocoelom, carries out these functions
4. none of their cells are far from the gastrovascular cavity or from the external environment

D

How many of the following characteristics of arthropods?

1. protostome development
2. bilateral symmetry
3. a pseudocoelom
4. three embryonic germ layers
5. a closed circulatory system

1. one of these
2. two of these
3. three of these
4. four of these

C

If you wanted to show your friends what a lophophore is and how it works, you would point out a feeding:

1. gastropod
2. sponge
3. hydra
4. ectoproct

D

The possession of two pairs of antennae is a characteristic of:

1. crustaceans
2. spiders
3. insects
4. millipedes

A

The members of which clade in the phylum Cnidaria occur only as polyps?

1. Anthozoa
2. Hydrozoa
3. Scyphozoa
4. Cubozoa

A

Vertebrates and tunicates share:

1. a notochord and a dorsal, hollow nerve cord
2. a high degree of cephalization
3. jaws adapted for feeding
4. an endoskeleton that includes a skull

A

In which vertebrates must fertilization always be interal?

1. chondrichthyans, osteichthyans, and reptiles
2. reptiles and amphibians
3. chondrichthyans, osteichthyans, and mammals
4. reptiles and mammals

D

Which of these statements accurately describes a similarity between sharks and ray-finned fishes?

1. they have a lateral line that is sensitive to changes in water pressure
2. a swim bladder helps control buoyancy
3. they are equally able to exchange gases with the environment while stationary
4. they are highly maneuverable due to their skeletal flexibility

A

Which of the following is a diploblastic phylum of completely aquatic predators?

1. Arthropoda
2. Mollusca
3. Annelida
4. Cnidaria

D

The larvae of many common tapeworm species that infect humans are usually found:

1. crawling in the abdominal blood vessels of cows and pigs
2. crawling in the intestines of cows and pigs
3. encysted in the muscles of an animal, such as a cow or pig
4. encysted in freshwater snails

C

What do all craniates have that earlier chordates did not have?

1. partial or complete skull
2. bone
3. vertebrae
4. a brain

A

A sponge's structural materials (spicules, spongin) are manufactured by what type of cell?

1. amoebocytes
2. epidermal cells
3. pore cells
4. choanocytes

A

You find a small animal with eight legs crawling up you bedroom wall. Closer examination will probably reveal that this animal has:

1. chelicerae
2. wings
3. two pairs of antennae
4. a head, thorax, and abdomen

A

Which of the following describe echinoderms?

1. hemolymph circulates circulates in the water vascular system
2. tube feet provide motility in most species
3. they are found in both freshwater and saltwater environments
4. they have an exoskeleton of hard calcareous plates

B

Which group's members have had both lungs and gills during their adult lives?

1. lancelets
2. lungfishes
3. amphibians
4. ichthyosaurs and plesiosaurs

B

Internal fertilization, leathery amniotic egg, and skin that resists drying are characteristics of:

1. amphibians
2. nonbird reptiles
3. bird
4. chondrichthyans

B

Which mollusk clade includes members that undergo embryonic torsion?

1. gastropods
2. bivalves
3. chitons
4. cephalopods

A

The water vascular system of echinoderms:

1. functions in locomotion and feeding
2. function the same as the gastrovascular cavity of flatworms
3. moves water through the animals body during suspension feeding
4. functions as a circulatory system that distributes nutrients to body cells

A

Why is the amniotic egg considered an important evolutionary breakthrough?

1. it permits internal fertilization to be replaced by external fertilization
2. it allows deposition of eggs in a dry terrestrial environment
3. it has a shell that increased gas exchange
4. it provides insulation to conserve heat

B

Which phylum captures prey using sticky colloblast cells?

1. Cnidarians
2. Polychaetes
3. Ctenophores or 'comb jellies'
4. Rotifers

C

How many of the following are characteristics of at least some members of the phylum Cnidaria?

1. a gastrovascular cavity with one entrance/exit
2. a polyp stage
3. a medusa stage
4. cnidocytes
5. a pseudocoelom

1. two of these
2. three of these
3. four of these
4. all of these

C

A terrestrial slug, a clam, and an octopus all share:

1. embryonic torsion
2. a mantle
3. ability to change color
4. gills

B

Sponges are most accurately described as:

1. marine filter feeders
2. marine predators
3. aquatic predators
4. aquatic filter feeders

D

Which of the following animal groups is entirely aquatic?

1. Amphibia
2. Mollusca
3. Echinodermata
4. Arthropoda

C

Lampreys differ from hagfishes in:

1. having a notochord that is surrounded by a tube of cartilage
2. lacking jaws
3. having pharyngeal clefts that develop into pharyngeal slits
4. having a cranium

A

The presence of a swim bladder allows the typical ray-finned fish to stop swimming and still:

1. avoid sinking
2. use its swim bladder as a respiratory organ
3. effectively circulate its blood
4. be highly maneuverable

A

A terrestrial mollusk without a shell belongs to which clade?

1. bivalves
2. cephalopods
3. chitons
4. gastropods

D

The heartworms that can accumulate within the hearts of dogs and other mammals have a pseudocoelom, an alimentary canal, and an outer covering that is occasionally shed. To which phylum does the heartworm belong?

1. Platyhelminthes
2. Annelida
3. Arthropoda
4. Nematoda

D

Which living chordates are postulated to be most like the earliest chordates in appearance?

1. chondrichthyans
2. amphibians
3. lancelets
4. adult turnicates

C

Against which stiff structure do the circular and longitudinal muscles of annelids work?

1. hydrostatic skeleton
2. cuticle
3. endoskeleton
4. bristles

A

The swim bladder of ray-finned fishes:

1. developed into lungs in saltwater fishes
2. helps regulate buoyancy
3. first appeared in sharks
4. can be used as a lung

B