Bio Exam 2 - Hw Questions

The Bohr shift on the oxygen-hemoglobin dissociation curve is produced by changes in _____ A.hemoglobin concentration B.temperature C.the partial pressure of oxygen D.pH

Which of the following statements comparing respiration in fish and in mammals is correct? A.The movement of the respiratory medium in mammals is bidirectional, but in fish it is unidirectional. B.In blood, oxygen is primarily transported by plasma in fish, but by red blood cells in mammals. C.A countercurrent exchange mechanism between the respiratory medium and blood flow is seen in mammals but not in fish. D.The respiratory medium for fish carries more oxygen than the respiratory medium of mammals.

You are a physician, and you are seeing a patient who complains of abnormal fatigue during exercise. You find that the immediate problem is a buildup of carbon dioxide in the tissues. What is the most likely cause? A.abnormal hemoglobin B.abnormally shaped platelets C.not enough hemoglobin D.abnormal carbonic anhydrase

Compared with the interstitial fluid that bathes active muscle cells, blood reaching these cells in arteries has a A.higher P(O2). B.higher P(CO2). C.greater bicarbonate concentration. D.lower pH. E.lower osmotic pressure.

In which of the following animals are the blood and the interstitial fluid considered to be the same body fluid? A.sparrows B.fishes C.grasshoppers D.dogs E.jellyfish and cnidarians

Which of the following best describes an artery? A.Arteries have thin walls compared with veins. B.Arteries carry oxygenated blood. C.Arteries carry blood away from the heart. D.Arteries contain valves. E.Arteries carry blood away from capillaries

In an open circulatory system, blood is _____. A.not always confined to blood vessels and is under lower pressure than in closed circulatory systems B.always inside of vessels and is under lower pressure than in closed circulatory systems C.always inside of vessels and is under higher pressure than in closed circulatory systems D.not always confined to blood vessels and is under higher pressure than in closed circulatory systems

Which statement regarding the mammalian heart is correct? A.Blood arrives at the heart via the ventricles. B.Blood is pumped from the heart via the atria. C.In the adult heart, blood in the right chambers of the heart cannot enter the left chambers without passing through the lungs. D.Oxygen-loaded blood moves only through the right side of the heart. E.When the right atrium contracts, it forces blood into the left atrium.

A human red blood cell in an artery of the left arm is on its way to deliver oxygen to a cell in the thumb. To travel from the artery to the thumb and then back to the left ventricle, this red blood cell must pass through _____. A.four capillary beds B.three capillary beds C.two capillary beds D.one capillary bed

Small swollen areas in the neck, groin, and axillary region are associated with _____ A.increased activity of the immune system B.dehydration C.blood sugar that is abnormally high D.sodium depletion

An advantage of gas exchange in fresh water, compared with gas exchange in air, is that _____. A.water loss through evaporation across the respiratory surface can be minimized B.water usually contains a higher concentration of oxygen than air C.the respiratory surface does not have to be as extensive in water D.ventilation requires less energy in water E.water is easier to move over the respiratory surface

The smallest airway through which inspired air passes before gas exchange occurs in the mammalian lungs is the _____ A.larynx B.trachea C.pharynx D.bronchus E.bronchiole

Which secretion is not a barrier that prevents pathogens from entering the body? A.Mucus. B.Antigens. C.Ear wax. D.Lysozyme.

True or false? The leukocytes of the innate immune system are B cells, macrophages, and neutrophils.

How do cells involved in the innate immune response detect the presence of pathogens? A.Antibodies bind to the pathogens. B.Leukocytes recognize the entire pathogen. C.Leukocytes recognize unique molecules on pathogens D.Leukocytes recognize the secretions from a pathogen.

Which of the following cells can engulf a pathogen? A.Mast cells. B.Platelets. C.Macrophages. D.Cytokines.

Which of the following statements best describes the role of mast cells in the inflammatory response? A.They release chemicals that constrict blood vessels at some distance from the wound site. B.They release chemicals that dilate blood vessels near the wound site, allowing blood components to enter the region from the bloodstream. C.They secrete substances that degrade bacterial cell walls and engulf and digest the invaders. D.They release cytokines to stimulate the release of additional neutrophils and macrophages.

Which of the following events occurs first when a wound that breaks the skin has occurred? A.Macrophages present bacterial proteins as antigens on their plasma membrane. B.Neutrophils secrete substances that degrade bacterial cell walls. C.Mast cells secrete chemical messengers to regulate blood flow to the wound. D.Platelets release proteins that form clots and decrease bleeding.

The site of inflammation may become swollen due to the increased numbers of cells and fluids at the site and painful due to signals from pain receptors. TRUE OR FALSE

Innate immunity and acquired immunity are both _____ A.dependent exclusively on cell-mediated responses B.dependent on tears, saliva, and mucous secretions that contain lysozyme, an enzyme that digests bacterial cell walls C.dependent on surface secretions from sebaceous and sweat glands, which give the skin an acidic pH that is unfavorable for bacterial colonization D.based on the trapping of microbes by mucus E.characteristics of all vertebrate animals

An antigen _____. A. is a protein molecule that helps defend the body against disease B.is a foreign molecule that evokes a specific response by a lymphocyte C.could be an invading bacterium D.induces development of white blood cells in the bone marrow E.is a protein attacked by an invading microorganism

The fact that there are about a million different antigen receptors possible in human B cells is based on _____. A.having one million different immunoglobulin genes B.recombination of the segments of the receptor DNA that make up the functional receptor genes of differentiated B cells C.the capacity of memory cells to produce antibodies D.constant changes in the splicing pattern of receptor genes after the differentiation of the B cell E.temporary changes in the ways that RNA is spliced in the B cells

Which of these cells is a phagocytic leukocyte that can engulf a foreign bacterium? A.plasma cell B.cytotoxic T cell C.B cell D.helper T cell E.macrophage

_____ interact with the antigen-class II MHC complex presented by macrophages. A.Cytotoxic T cells B.B cells C.Bacterial cells D.Helper T cells E.Epithelial cells

B cells that have been stimulated by interleukin-2 develop into _____ A.antigens B.cytotoxic T cells C.helper T cells D.plasma cells E.macrophages

The role of cytotoxic T cells is the secretion of _____, which plays a role in the _____ immune response. A.perforin ... humoral B.perforin ... cell-mediated C.interleukin-2 ... humoral D.antibodies ... humoral E.antibodies ... antibody-mediated

Clonal selection is the division of _____ that have been stimulated by binding to an antigen, which results in the production of cloned _____. A.helper T cells ... plasma cells B.B cells ... macrophages C.B cells ... plasma cells and memory cells D.macrophages ... B cells and T cells E.T cells ... B cells

Which of these cells is responsible for the rapidity of the secondary immune response? A.cytokines B.cytotoxic T cells C.macrophages D.plasma cells E.memory cells

Which of these cells produce and secrete antibodies? A.plasma cells B.macrophages C.bacterial cells D.helper T cells E.cytotoxic T cells

Extracellular pathogens such as viruses and bacteria in body fluids are attacked by _____. A.complement proteins B.antigens C.helper T cells D.antibodies from plasma cells E.cytotoxic T cells

Tissues are immunogically "typed" before an organ transplant to make sure that the donor and recipient match as closely as possible in their _____. A. histamines B. T cells C. antibodies D. B cells E. MHC (major histocompatibility complex) proteins

A primary reason for needing a new vaccine for influenza each year is that _____. A. immunity typically disappears one month after recovery from a disease B. the first infection with influenza weakens the immune system C. mutation in the influenza virus is frequent D. the influenza virus might proliferate in different tissues during each subsequent year, and immune memory is limited to those tissues initially infected E. influenza is a disease that causes the apoptosis of all memory cells

Inflammatory responses typically include _____. A. release of substances to decrease the blood supply to an inflamed area B. increased activity of phagocytes in an inflamed area C. reduced permeability of blood vessels to conserve plasma D. inhibiting the release of white blood cells from bone marrow

What is the role of recombinase in generating lymphocyte diversity? A. Recombinase splices RNA to produce variable transcripts. B. Recombinase combines DNA from human and viral origin. C. Early in B cell development, recombinase links one light-chain V gene segment to one J gene segment.

How does an antihistamine reduce allergy symptoms? A. An antihistamine binds pollen antigens, preventing them from provoking an allergic reaction. B. An antihistamine kills mast cells, blocking an allergic reaction. C. An antihistamine blocks receptors for inflammatory chemicals released from granules within mast cells.

Which of the following is the best definition of autoimmune disease? A. a condition in which the immune system creates random antibodies without being triggered by an antigen B. a condition in which B cells and T cells respond independently to antigens and do not interact correctly C. a condition in which the adaptive immune system fails to recognize the second infection by the same antigen D. a condition in which self molecules are treated as non-self