Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

MCAT biology > anatomy and physiology of circulatory system (heart and blood) > Flashcards

anatomy and physiology of circulatory system (heart and blood) Flashcards

1
Q

arteries carry blood?

A

away from the heart at high pressure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

veins carry blood?

A

towards the heart at low pressure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

arteries branch into?

A

arterioles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

arterioles pass into?

A

capillaries which are only wide enough for a single blood cell to pass at a time

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

after blood passes through capillaries, it passes through?

A

venules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

venules pass back into?

A

veins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

all exchange of materials in the blood happen where?

A

capillaries

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

the walls of blood vessels are what type of cell?

A

endothelial cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

vasodilation/vasoconstriction is when?

A

secretion of substances (like nitric acid) and endothelium regulate vessel diameter to maintain blood pressure, tissue oxygenation, and thermoregulation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

inflammation is when?

A

release of inflammatory chemicals from injured tissues stimulate endothelial cells to increase their expression of adhesion molecules which allow WBC to adhere to the endothelial cell to enter injured tissue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

angiogenesis is?

A

then formation of new blood vessels
ex: many tumors secrete angiogenic growth factors to increase blood supply thus angiogenesis inhibitors are drugs used to restrict blood flow to tumors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

thrombosis is?

A

blood clotting

*undamaged endothelial cells secrete substances to inhibit coagulation to prevent life-threatening clots

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

pulmonary circulation is defined as?

A

flow of blood from the heart to the lungs and back to the heart

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

systematic circulation is defined as?

A

flow of blood from the heart to the rest of the body and back again

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

one exception to circulation system is the hepatic portal system, which is when?

A

blood passes first through capillaries in the intestine, the collects in veins to travel to the liver where the vessels branch and blood passes again through capillaries
*important for nutrients directly from intestine to liver

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

second exception to circulation system is the hypothalamic-hypophysial portal system, which is when?

A

blood passes through capillaries in the hypothalamus to the portal veins, then to capillaries in the pituitary
*important for hormones from hypothalamus directly to pituitary

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

atrioventricular valves are located?

A

between each atrium and ventricle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

the AV valve between the left atrium and left ventricle is the?

A

bicuspid/mitral valve

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

the AV valve between the right atrium and right ventricle is the?

A

tricuspid valve

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

the semilunar valve between right ventricle and pulmonary artery is?

A

pulmonary semilunar valve

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

the semilunar valve between left ventricle and aorta is?

A

aortic semilunar valve

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

what happens during diastole?

A

ventricles are relaxed and atria contract

blood is able to flow into ventricles from the atria

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

what happens during systole?

A

ventricles contract and atria relaxed
blood is pushed out of ventricles towards pulmonary artery or aorta
*lub dup sound

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

heart rate/pulse is the?

A

number of times the “lub-dup” cardiac cycle is repeated per minute

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

stroke volume is?

A

the amount of blood pumped with each systole

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

cardiac output is?

A

the total amount of blood pumped per minute

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

the heart is what type of muscle?

A

cardiac muscle (involuntary)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

the cardiac muscle is functional syncytium, meaning?

A

that the tissues’ cytoplasms communicate via gap junctions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

gap junctions of the cardiac muscle are found in?

A

intercalated disks which is the connection between cardiac and muscle cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

the initiation of each action potential to start each cardiac cycle occurs automatically within the heart itself by?

A

the SA node located in right atrium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

the SA (sinoatrial) node acts as a?

A

pacemaker and is divided into three phases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

membrane potential in cardiac muscle cell

phase 0 is depolarization, what happens?

A

AP simulates myocytes to reach threshold causing the
fast Na+ channels open
Na+ influx

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

membrane potential in cardiac muscle cell

phase 1 is initial repolarization, what happens?

A

Na+ channels inactivate and K+ channels open causing

K+ efflux

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

membrane potential in cardiac muscle cell

phase 2 is plateau, what happens?

A

the Na+ influx from phase 0 causes Ca2+ channels to open, so Ca2+ influx
K+ channels are still open so K+ efflux are balanced leading the equilibrium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

membrane potential in cardiac muscle cell

phase 3 is repolarization, what happens?

A

Ca2+ channels close but K+ remain open for K+ efflux

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

membrane potential in cardiac muscle cell

phase 4 is resting membrane potential, what happens?

A

inward and outward are equal thus K+ closes

37
Q

the SA node spreads throughout the atria causing them to ?

A

contract and fill ventricles

38
Q

the SA node triggers the AV node which?

A

continues electrical impulse to the AV bundle (bundle of His)

39
Q

the AV bundles divided into what two sections?

A

left bundle branches and purkinje fibers

40
Q

why does the AV bundles divide into left bundle branches and purkinje fibers?

A

to allow impulse to spread rapidly and evenly over both ventricles

41
Q

what controls the SA node?

A

the vagnus nerve which the preganglionic axons of it synapose in the ganglia near the SA node

42
Q

what neurotransmitter is released by the vagus nerve to inhibit depolarization by binding to receptors on the cells of the SA node?

A

acetylcholine

43
Q

hemodynamics is?

A

the study of blood flow

44
Q

what is the driving force of blood flow?

A

difference in pressure from arteries to veins

45
Q

blood pressure is systemic arterial pressure is, this is the measurement of?

A

force per unit area exerted by blood upon the walls of arteries

46
Q

the typical bp is 120/80 where the numbers mean?

A

120mmHg is the systolic pressure which is the highest pressure that ever occurs in the circulatory system
80mmHg is the diastolic pressure which is the lowest pressure that ever occurs in the circulatory system

47
Q

what measures blood pressure?

A

sphygmomanometer

48
Q

local auto-regulation is the process known as?

A

when tissues in need of extra blood flow are able to requisition it themselves

49
Q

blood is composed of?

A

plasma and formed elements

50
Q

plasma accounts for 54% of blood volume is consists of what items?

A

electrolytes, buffers, sugars, blood proteins, lipoproteins, co2, o2, and metabolic waste

51
Q

buffers in the blood are there to? what is the primary one?

A

maintain a constant pH of 7.4
bicarbonate (HCO3-)
via the reaction CO2+H2O=H2CO3=HCO3-+H+

52
Q

the electrolytes of the blood are?

A

sodium, potassium, chloride, calcium, and magnesium

53
Q

the blood protein, albumin is for?

A

maintenance of oncotic pressure which is the osmotic pressure in capillaries from plasma proteins

54
Q

the blood protein, immunoglobulins are for?

A

immune system

55
Q

the blood protein, fibrinogen is for?

A

blood clotting (hemostasis)

56
Q

lipoproteins of the blood are particles consisting of?

A

fats, cholesterol, and carrier proteins

57
Q

the main metabolic waste product of blood is?

A

urea which is essentially a carrier of excess nitrogen

58
Q

bilirubin is another blood waste product which is used for?

A

breakdown product of heme

59
Q

what is another term for RBC?

A

erythrocytes

60
Q

when centrifuged, the volume of blood that only has RBC is called the? and is what % of whole blood?

A

hematocrit - 45%

61
Q

what is another term for WBC?

A

leukocytes

62
Q

leukocytes and platelets make up what % of blood volume?

A

1%

63
Q

what hormone stimulates RBC production? and where does this production take place?

A

erythropoeitin (hormone from kidney)

production in the bone marrow

64
Q

RBC lack a mitochondria thus rely on what for ATP synthesis?

A

glycolysis

65
Q

the purpose of RBC are to?

A

transport o2 to tissues from the lungs and co2 from tissues back to the lungs

66
Q

what shape are typical RBC? why?

A

flat and biconcave to increase surface area of hemoglobins to bind to oxygen

67
Q

what is blood type based on?

A

presence or absence of specific antigens

68
Q

what are the two most important blood antigen groups?

A

ABO blood group

Rh blood group

69
Q

hemolytic disease of the newborn/erythroblastosis fetalis is when?

A

mother is Rh- and carrying a Rh+ baby

70
Q

a person with A+ blood will produce what type of antibodies?

A

anti-B antibodies so that it will clump and destroy B cells

71
Q

granulocytes are class of WBC including?

A

neutrophils, eosinphil, and basophil

72
Q

lymphocytes are class of WBC including?

A

T cells and B cells

73
Q

monocytes are class of WBC including?

A

macrophages

74
Q

what WBC is phagocytic to bacteria and creates pus?

A

neutrophils

75
Q

what WBC is the most abundant?

A

neutrophils

76
Q

what WBC destroys parasites and are modulators to allergic reactions?

A

eosinophils

77
Q

what WBC stores and releases histamine for allergic reactions and attracts other WBC to inflamed sites?

A

basophils

78
Q

what WBC is the rarest?

A

basophils

79
Q

what WBC mature into plasma cells that produce antibodies?

A

B cells

80
Q

what WBC control immunity and attack virus infected cells/tumor cells?

A

T cells

81
Q

what WBC is phagocytic to debris and microorganisms and activate lymphocytes (T and B cells)?

A

macrophages

82
Q

what WBC is the largest in size?

A

macrophages

83
Q

platelets are small fragments of what?

A

megakaryocytes, which are derived from thrombopoietin

84
Q

the purpose of platelets are to?

A

aggregate at site of damage to a blood vessel wall to for platelet plug to stop bleeding and activate other clotting factors

85
Q

when none of the four subunits of hemoglobin are bound to, what confirmation happens? and what is the affinity?

A

tense and has low affinity for o2

when o2 does bind, it becomes relaxed and affinity increases

86
Q

hemoglobin binds oxygen cooperatively, meaning?

A

the confirmation change in one subunit, activates the affinity for other subunits to bind

87
Q

bohr effect happens when what factors stabilize tense hemoglobin and reduce oxygen affinity?

A

decreased pH, increase Pco2, and increased temperature

88
Q

what are the three ways carbon dioxide is transported in the blood?

A

conversion of co2 to carbonic acid which dissociates into bicarbonate and proton by carbonic anhydrase enzyme (73%)
being stuck to hemoglobin by binding to other sites on the protein (20%)
co2 is water soluble therefore dissolve in blood more so than o2 does (7%)

MCAT biology (13 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions