BIOLOGY II MIDTERM 2 COMPLETE
QUESTIONS AND DETAILED SOLUTIONS
◉fibrin clot formation. Answer: stronger, permanent clot; fibrin
polymerizes long threads of fibrin that stick to damaged vessel and
blood cells and platelets become trapped in the network
◉clotting factors. Answer: produced and secreted by the platelets,
damaged cells, and ones in plasma
◉hemophilia A. Answer: factor 7 is missing
◉prothrombin. Answer: plasma protein that is produced in the liver
◉thrombin. Answer: enzyme that catalyzes the conversion of
fibrinogen into fibrin
◉anticlotting factors in blood. Answer: prevent spontaneous clotting
in absence of vessel damage
,◉thrombus. Answer: clot that forms within blood vessel, blocking
blood flow
◉atherosclerosis. Answer: hardening of the arteries due to
accumulation of fatty deposits
◉LDL. Answer: delivers cholesterol for membrane production
◉HDL. Answer: scavenges excess cholesterol and returns to liver
◉heart attack (myocardial infarction). Answer: results from one or
more of the coronary arteries blocked by plaque or thrombi;
blockage to arteries can lead to damage or death to the cardiac
muscle
◉stroke. Answer: death of nervous tissue in the brain due to lack of
oxygen; can result from arterial blockage
◉defense system. Answer: protects against pathogens and foreign
molecules
◉innate immunity. Answer: provides general protection against
pathogens; deters a wide range of pathogens and does this by
,preventing entrance into body or destroying the pathogen quickly if
it enters
◉adaptive immunity. Answer: specific responses directed toward
specific antigens
◉hemocytes. Answer: travel through body hemolymph and ingest
bacteria and break them down; secrete antimicrobial peptides
◉natural killer cells. Answer: circulate, recognize abnormal surface
proteins on virus-infected or cancerous cells, do attack pathogens
directly
◉interferons. Answer: virus infected cells help other cells resist
virus
◉arteries. Answer: take blood away from heart to organs; divide
into arterioles which deliver blood to capillaries
◉capillaries. Answer: microscopic blood vessels; exchange takes
place between tissues and blood; composed of endothelium and
basal lamina; only location for exchange of substances between
blood and interstitial fluid
, ◉basal lamina. Answer: extracellular layer
◉venules. Answer: capillaries merged together
◉capillary beds. Answer: networks of capillaries that infiltrate
tissues
◉veins. Answer: receive blood from venules; located between
muscles (movement of muscles puts pressure on veins); valves
prevent backflow; blood moves back to heart
◉atrium. Answer: receive blood from tissues (via veins)
◉ventricle. Answer: pump blood into arteries
◉pericardium. Answer: sac that encloses the heart
◉fish. Answer: characterized by single circulation; 1 atrium 1
ventricle; blood flow is a single circuit
◉amphibians. Answer: double circulation; 2 atria and 1 ventricle