physiology of the cardiovascular system

Question 1

the force per unit area exerted on the wall of the blood vessels is measured by ________________

Answer 1

sphygmomanometer

Question 2

what do sphygmomanometers measure?

Answer 2

the pressure above and beyond the atmospheric pressure

Question 3

blood pressure is expressed as a ratio of _________ over _________

Answer 3

systolic (ventricular contraction)
diastolic (ventricular relaxation)

Question 4

pressure gradually drops from the aterial to venous circulation, with the largest drop occuring at the ___________

Answer 4

arterioles

Question 5

how are pressure differential, cardiac output, and total peripheral resistance mathematically related?

Answer 5

P = CO (TPR)

Question 6

arterioles and capillaries act much like _________________ in a circuit

Answer 6

resistors

*limits the flow of electricity

Question 7

the longer the blood vessel, the (more / less) resistance it offers

Answer 7

more

Question 8

the larger area of a blood vessel, the ( more / less) resistance it offers

Answer 8

less

Question 9

T / F - with the exception of the three portal systems, all systemic capillary beds are in parallel with each other

Answer 9

true

Question 10

because all systemic capillary beds are in parallel, the opening of them will (increase / decrease) vascular resistance

Answer 10

decrease

Question 11

____________ are specialized neruons that detect changes in the mechanical forces on the walls of the vesselq

Answer 11

baroreceptors

Question 12

when blood pressure is too low, baroreceptors can stimulate the sympathetic nervous system which causes (vasodilation / vasoconstriction), thereby (increasing / decreasing) blood pressure

Answer 12

blood pressure = too low
sympathetic nervous system = vasocontriction
increasing blood pressure

Question 13

_____________ can sense when the osmolarity of the blood is too high

Answer 13

chemoreceptors

Question 14

dehydration (high blood osmolarity) promotes the release of _____________

Answer 14

ADH

Question 15

what does ADH do?

Answer 15

increases the reabsorption of water, thereby increasig blood volume and pressure

Question 16

low perfusion of the jaxtaglomerular cells of the kidney stimulates _______________ release

Answer 16

aldosterone

*through the renin-angiotensin-aldosterone system

Question 17

aldosterone increasing the reabsorption of ______________ and (increases / decreases) blood volume and pressure

Answer 17

sodium (water indirectly)
increases

Question 18

_________________ aid in the loss of salt within the nephron, acting as a natural diuretic with loss of fluid

Answer 18

ANP

Question 19

oxygen is carried by ___________ in the blood

Answer 19

hemoglobin

Question 20

what type of reaction is the binding / releasing of oxygen to or from the iron atom in the heme group?

Answer 20

oxidation-reduction

Question 21

in the lungs, oxygen diffuses into the ______________

Answer 21

alveolar capillaries

Question 22

_____________ makes it easier for subsequent oxygen molecules to bind / release to / from the reamining three heme groups

Answer 22

cooperative binding

Question 23

cooperative binding gives hemoglobin dissociation its classic ____________ shape

Answer 23

sigmoidal

Question 24

T / F - CO2 can be carried by hemoglobin

Answer 24

true

*hemoglobin has a much higher affinity for O2

Question 25

____________ catalyzes the combination reaction between carbon dioxide and water to for carbonic acid

Answer 25

carbonic anhydrase

Question 26

why is carbonic acid a more effective way of transporting metabolic waste to the lungs?

Answer 26

carbonic acid will dissociate into an H+ and a bicarbonate ion (HCO3-) both of these moelculaes are ions and have high solubilities in water

Question 27

increased CO2 production will cause a __________ shift in the bicarbonate buffer equation, resulting in a (increased / decreased) H+ concentration and a (higher / lower) pH

Answer 27

right higher H+ lower pH

Question 28

what happens to the hemoglobin's affinity for O2 when there is an abundance of H+?

Answer 28

the affinity decreases, hemoglobin is more likely to release the O2 *bohr effect

Question 29

in addition to high H+ concentrations, what are other reasons you may see a right shift in the hemoglobin dissoiation curve?

Answer 29

increased temp increase 2,3 BPG concentrations (side product of glycolysis)

Question 30

T / F - fetal Hb have a higher affinity for O2 that adult Hb

Answer 30

true *fetal RBCs have to pull oxygen off maternal Hb and onto fetal Hb

Question 31

if a person is hyperventilating, what way will the biocarbonate buffer system shift? what will happen to the pH?

Answer 31

hyperventilation = CO2 is exhaled CO2 + H2O --> H2CO3 --> H+ + HCO3- low CO2 shift left lower H+ pH = increase

Question 32

carbohydrates and amino acids are absorbed into the __________ of the small intestine

Answer 32

capillaries

Question 33

fats are absorbed into the __________ of the small intestine

Answer 33

lacteals

Question 34

wastes (CO2, ammonia, urea) enter the bloodstream via ____________

Answer 34

moving down their gradients from tissues to capillaries

Question 35

hormones enter the cirulation in / near the organ via ___________

Answer 35

exocytosis

Question 36

___________ hormones reach their target tissues and activate cell surface receptors

Answer 36

peptide

Question 37

____________ hormones reach their target tissues and activate intranuclear receptors

Answer 37

steroid

Question 38

_______________ pressure is the force per unit area that the blood exerts against the vessel walls

Answer 38

hydrostatic pressure

Question 39

how is hydrostatic pressure generated?

Answer 39

contraction of the heart elasticity of the arteries

Question 40

hydrostatic pressure pushes fluid ______ the bloodstream

Answer 40

out of the blood stream *into the interstitium

Question 41

______________ is the pressure generated by solutes as they attempt to draw water into the bloodstream

Answer 41

osmotic pressure

Question 42

if hydrostatic pressure is much larger than oncotic pressure, then there is a net (influx / efflux) of water

Answer 42

efflux (out) hydrostatic = out of osmotic / oncotic = into

Question 43

why are the starling forces important?

Answer 43

starling forces = the balance of hydrostatic and osmotic pressure it is essential for maintaing the proper fluid volumes and solute concentrations inside and outside the vasculature

Question 44

most lymph is returned to the central circulatory system by way of a channel called the ____________

Answer 44

thoracic duct

Question 45

____________ protect the vascular system in the even of damage by forming a clot

Answer 45

platelets

Question 46

what are clots composed of?

Answer 46

cogulation factors (proteins) platelets

Question 47

when the endothelium of a blood vessel is damaged, what becomes exposed?

Answer 47

underlying connective tissue *contains collagen and tissue factor (protein)

Question 48

cogulation factors are secreted by the ____________

Answer 48

liver

Question 49

cogulation factors initiate a complex activation cascade that works to active prothrombin to form _____________

Answer 49

thrombin *this occurs via thromboplastin

Question 50

thrombin can convert ___________ into _______________

Answer 50

fibrinogen to fibrin

Question 51

what is fibrin used for in blood clotting?

Answer 51

fibrin forms small fibers that aggregate and coss link into a woven structure that captures red blood cells and other platelets, forming a clot over the damage

Question 52

eventually the clot will be broken down by ___________

Answer 52

plasmin *inactive form = plasminogen