Chapter 42 Key Terms Flashcards
the process by which small molecules move between cells and their surroundings
diffusion
present in animals that lack a circulatory system; function in both digestion and distribution of substances throughout body; the body wall that encloses _________ is only two cells thick
gastrovascular cavities
a circulatory system has
circulatory fluid, set of interconnecting vessels, muscular pump (heart)
circulatory fluid in insects, arthropods, and some molluscs
hemolymph
______circulatory system: circulatory fluid bathes organs directly
open
_____ circulatory system: blood is confined to vessels and is distinct from interstitial fluid
closed
annelids, cephalopods and vertebrates have _________ circulatory systems
closed
humans and other vertebrates have a closed circulatory system called the___________system
cardiovascular
3 main types of blood vessels
arteries, veins, capillaries
how many directions does blood flow in these vessels
one way
which vessels carry blood away from the heart to capillaries?
arteries
arteries branch into _________
arterioles
networks of capillaries are called______
capillary beds
sites of chemical exchange between the blood and interstitial fluid
capillary beds
______________ converge into veins and return blood from capillaries to the heart
venules
one of the 3 types of vessels that returns blood to the heart from the capillaries
veins
how many chambers do vertebrate hearts have?
2 or more
blood enters the heart through the ? and is pumped out through
atria, ventricles
sharks, rays, and bony fishes have this kind of circulation
single circulation
blood leaving the heart passes through two capillary beds before returning
single circulation
amphibians, reptiles, and mammals have this kind of circulation
double circulation
oxygen poor blood is pumped from the right side of the heart in one circuit; oxygen rich blood is pumped from left side of the heard in a separate circuit
double circulation
how many chambers do frogs/amphibians have in their heart?
3: two atria and one ventricle
how many chambers do mammals and birds have?
4: two atria and two ventricles
(in mammals) the _____ have relatively thin walls and serve as collection chambers for the blood returning to the heart
atria
(in mammals) the _____ have thicker walls and contract much more forcefully
ventricles
the relaxation or filling phase
diastole
the contraction/pumping phase
systole
the rhythmic cycle in which the heart contracts and relaxes
the cardiac cycle
the volume of blood pumped into the systemic circulation per minute and depends on both the heart rate and stroke volume
cardiac output
number of beats per minute
heart rate
amount of blood pumped in a single contraction
stroke volume
what prevents the backflow of blood into the heart?
4 valves
valves that separate each atrium and ventricle
atrioventricular valves(AV)
valves that control blood flow to the aorta and pulmonary artery
semilunar valves