Unit 3

Ammonia: a)is soluble in water. b)has low toxicity relative to urea. c)is metabolically more expensive to synthesize than urea. d)is the major nitrogenous waste excreted by insects. e)is the major nitrogenous waste product excreted by humans and birds.

A

For a molecule of CO2 released into the blood in your right toe to eventually travel out of your nose, it must pass through all of the following structures except the: a)pulmonary vein b)alveolus c)trachea d)right ventricle e)right atrium

A

The immune system releases molecules of _______ that cause the redness, heat, and swelling of the inflammatory response (as well as the itching, sneezing, and runny nose of an allergic reaction). a)histamine b)antibody c)adrenaline d)antigen e)allergen

A

The metabolic rate of a fasting, non-stressed ectotherm at rest at a specific temperature is called: a)SMR b)BMR c)STP d)ATP e)ECG

A

These autorhythmic cells located in the wall of the right atrium control the rate and timing at which all cardiac muscle cells contract. a)Sinoatrial (SA) node b)Atroventrical (AV) node c)Semilunar (SL) node d)Purkinje fibers e)Bundle branches

A

Which of the following would prevent allergic attacks? a)blocking the attachment of the IgE antibodies to the mast cells b)blocking the antigenic determinants of the IgM antibodies c)reducing the number of helper T cells in the body d)reducing the number of cytotoxic cells e)increasing the initial exposure to the antigen

A

A human who has no access to fresh water but is forced to drink seawater instead will: a)thrive under such conditions, as long as he has lived at the ocean most of his life. b)excrete more water molecules than taken in, because of the high load of ion ingestion. c)develop structural changes in the kidneys to accommodate the salt overload. d)risk becoming overhydrated within twelve hours.

B

B cells and T cells that do not immediately attack pathogens, but instead remain inactive until a future encounter with the pathogen, are referred to as: a)leukocyte reservoir cells b)memory B cells and memory T cells c)stem B cells and stem T cells d)residual lymphocytes e)MHC factors

B

Calculate the heart rate of an individual with a cardiac output of 10 L/min and a stroke volume of 100 mL. a)1000 mL/min b)100 beats/min c)200 beats/min d)100 mL/beat e)50 mL/beat/min

B

Homeostatic mechanisms: a)keep variables exactly at the set point. b)help to keep a relatively constant internal environment in the body. c)act to keep values out of the normal range. d)usually operate by positive feedback. e)produce most disease conditions.

B

How is positive feedback different from negative feedback? a)Positive feedback benefits the organism, but negative feedback is harmful. b)Positive feedback's effector responses are in the same direction as the initiating stimulus, whereas negative feedback's effector responses are in the opposite direction. c)In positive feedback, the effector's response increases some parameter (such as body temperature), whereas in negative feedback the parameter decreases. d)Positive feedback systems have only effectors, whereas negative feedback systems have only receptors. e)Positive feedback mechanisms are more frequently encountered in the control of homeostasis than negative feedback mechanisms.

B

Marine birds eliminate excess salts through their: a)kidneys b)salt glands in their heads c)general body surface (skin) d)all of the above e)none of the above

B

This flap of cartilage prevents food from entering the trachea. a)pharynx b)epiglottis c)larynx d)glottis e)esophageal sphincter

B

When a B cell encounters an antigen to which it is targeted, it divides rapidly and produces: a)more antigen b)plasma cells c)T cells d)Killer cells e)Interferons

B

Fat absorption differs from other foods because its breakdown products are: a)formed in the large intestine. b)absorbed directly into the blood. c)absorbed into the lacteals before entering into the lymphatic system. d)absorbed only when glucose is not present. e) converted into bile by the liver.

C

How do the digestion and absorption of fat differ from the digestion and absorption of carbohydrates? a)Processing of fats does not require any digestive secretions; processing of carbohydrates does. b)Fat absorption occurs in the stomach; carbohydrates are absorbed by the small intestine. c)Most absorbed fat first enters the lymphatic system; carbohydrates directly enter the blood. d)Carbohydrates need to be emulsified before they can be digested; fats do not. e)Fat must be worked on by bacteria in the large intestine before it can be absorbed; carbohydrates do not.

C

Most types of communication between cells rely on: a)the exchange of cytosol between the cells b)the movement of the cells c)chemical or electrical signals d)the exchange of DNA between the cells e)shortening of muscle cells

C

The body fluids of an osmoconformer would be _____ with its _____ environment. a)isosmotic; freshwater b)hyperosmotic; saltwater c)isosmotic; saltwater d)hyposmotic; saltwater e)hyposmotic; freshwater

C

The exchange of gases between interstitial fluid and the blood occurs in: a)arteries b)arterioles c)capillaries d)veins e)venules

C

The more concentrated the urine that a mammal can produce, the longer are its: a)glomeruli b)proximal convoluted tubules c)loops of Henle d)Bowman's capsules e)Malphighian tubules

C

Which of the following animals is correctly paired with its feeding mechanism? a)snake - fluid feeder b)baleen whale - substrate feeder c)clam - suspension feeder d)mosquito - bulk feeder

C

Which of the following is an evolutionary adaptation that enables animals with more complex body designs to ensure sufficient exchange with their environment? a)reduced plasma membrane surface area b)insulation c)highly folded internal surfaces d)increased body size e)increased cell volume

C

Which of the following most accurately describes selective permeability? a)An input of energy is required for transport. b)There must be a concentration gradient for molecules to pass through a membrane. c)Only certain molecules can cross a cell membrane. d)Molecules diffuse against their concentration gradients.

C

Which of the following statements concerning an open circulatory system is true? a)A heart is not required to pump the circulatory fluid. b)An open circulatory system has higher pressure and is less energy efficient than a closed system. c)The circulatory fluid is also the interstitial fluid. d)The circulatory fluid does not require respiratory pigments for O2 transport. e)The lower pressures provide for more effective delivery of O2 than is possible with a closed system.

C

Which of the following statements concerning type II diabetes is true? a)This form of diabetes usually appears during childhood. b)This form of diabetes results from the destruction of pancreatic beta cells by the immune system. c)Excess body weight and lack of exercise increase the risk of developing the disease. d)Fewer than 10% of people with diabetes have type II. e)All of the above are true statements.

C

Which type of surface marker is normally present on every nucleated cell in your body? a)B receptor b)T receptor c)Class I MHC d)Class II MHC e)all of the above

C

Why are measles vaccinations effective? a)They cause the inflammation response resulting in the production of antibodies that engulf the measles virus if it enters the body. b)They cause an immune response resulting in the production of cytotoxic T cells that remain in the blood attacking all viruses that enter the body. c)They cause an immune response resulting in the production of memory B cells that provide a rapid response if the individual is subsequently infected by the measles virus. d)They cause the inflammation response resulting in the production of memory T cells that provide a limited response if infected by the measles virus.

C

A major means for conserving heat is: a)enhanced sweating b)increased convective loss c)increased metabolic rate d)vasoconstriction of cutaneous blood vessels e)vasodilation of cutaneous blood vessels

D

As filtrate moves down the loop of Henle, the surrounding interstitial fluid has a _____ osmolality than the filtrate, so _____ leave(s) the filtrate. a)higher, water b)lesser, urea c)higher, urea d)lesser, water e)lesser, water and urea

D

In an open circulatory system, blood is: a)always inside of vessels and is under higher pressure than in closed circulatory systems. b)not always confined to blood vessels and is under higher pressure than in closed circulatory systems. c)always inside of vessels and is under lower pressure than in closed circulatory systems. d)not always confined to blood vessels and is under lower pressure than in closed circulatory systems.

D

Memory cells: a)produce allergens. b)are responsible for passive immunity. c)prevent an animal from encountering certain antigens. d)provide an accelerated immune response upon second exposure to a particular antigen. e)all of the above.

D

One of the waste products that accumulates during cellular functions is carbon dioxide. It is removed via the respiratory system. What other waste products may accumulate during normal physiological functioning in a vertebrate? a)ammonia and urea b)uric acid and urea c)ammonia and urea d)ammonia, uric acid, and urea

D

Vitamins are classified based on: a)whether they affect carbohydrate or proteins. b)how much of them is required. c)the amount of energy they contain. d)whether they are water soluble or fat soluble.

D

Which of the following kills invading microbes? a)lysozymes b)stomach acid c)intestinal enzymes d)all of the above e)none of the above

D

Which of the following would increase the rate of heat exchange between an animal and its environment? a)feathers or fur b)vasoconstruction near the skin c)blubber or a fat layer under the skin d)wind blowing across the body surface e)all of the above

D

Compare an animal with a gastrovascular cavity to an animal with a tube-type digestive system. What is(are) the major advantage(s) of having a tube? a)It allows the animal to consume a second meal while the first is being digested. b)It permits development of specialized enzymes and concentration of digestive juices in different regions. c)It permits more time for enzymatic action. d)Additional physical cutting and grinding of the food bolus is made possible. e)All of the above are advantages

E

During exhalation in humans, air moves from the bronchus into the: a) bronchioles b)alveoli c) nostrils d)pharynx e) trachea

E

Fluid is forced out of systemic capillaries at the arteriolar end because: a)The blood pressure is less than that of the interstitial fluid. b)The osmotic pressure of the interstitial fluid is greater than that of the blood. c)The osmotic pressure of the interstitial fluid is greater than the blood pressure. d)The osmotic pressure of the blood is greater than the hydrostatic pressure of the interstitial fluid. e)The blood pressure is greater than the osmotic pressure of the blood.

E

Which of the following is not a property of the adaptive immune system? a)receptor diversity b)lack of reactivity against host cells c)immunological memory d)very specific response to pathogens e)rapid rate of response

E