chapter 6

cardiac output

volume of blood pumped by the heart in 1 minute

Layers of the heart

epicardium, myocardium, and endocardium

Epicardium

thin, outer layer

Myocardium

Middle muscle layer

endocardium

Thin inner layer

Angina

chest pain due to reduced blood flow to the heart

atherosclerosis

buildup of plaque causing narrowing of coronary arteries and reduced blood flow to the heart

Myocardial ischemia

when blood flow (and oxygen) to the heart is reduced, usually due to blocked coronary arteries from plaque buildup

Myocardial infarction

when blood flow to part of the heart is blocked, usually by a blood clot in a narrowed coronary artery

right atrium receives…

deoxygenated blood from the body via superior and inferior vena cava

right atrium pumps blood to…

right ventricle

left atrium receives…

oxygenated blood from the lungs via pulmonary veins

left atrium pumps blood to the…

left ventricle

right ventricle receives blood from the…

right atrium

right ventricle pumps blood to the…

pulmonary veins (then to lungs to be oxygenated)

left ventricle receives blood from the…

left atrium

left ventricle pumps blood to the…

aorta (rest of the body)

tricuspid valve function

closes when the right ventricle contracts, and prevents blood from flowing back into the right atrium

bicuspid / mitral valve function

closes when the left ventricle contracts and prevents blood from flowing back into the left atrium

pulmonary valve

closes when the right ventricle relaxes and prevents blood from flowing back into the right ventricle

aortic valve function

closes when the left ventricle relaxes and prevents blood from flowing back into the left ventricle

What is occurring during the first “lubb” sound of heartbeat

ventricles contract, tricuspid and bicuspid valves close

What is occurring during the second “dubb” sound of heartbeat

ventricles relax, pulmonary and aortic valves close

SA node function

begins the heartbeat by generating electrical impulse that causes atria to contract and push blood into ventricles

Internodal pathway fibers function

relays impulse to AV node

AV node function

Picks up the impulse, slows it down while atria finishes contracting, and then relays it through bundle of His

AV bundle (bundle of his)

carry the impulse through the ventricles via Purkinje fibers, causing ventricular contraction and blood ejection, followed by a brief relaxation before the next heartbeat

systolic blood pressure

pressure in arteries during contraction of the ventricles

diastolic blood pressure

pressure in arteries during relaxation of the ventricles

pulmonary circulation only goes between the _____ and the _____

heart; lungs

goal of pulmonary circulation

to oxygenate blood

goal of systemic circulation

to deliver oxygen to body

largest artery

aorta

arteries carry…

oxygenated blood away from the heart and to the tissues

pulmonary arteries carry…

deoxygenated blood from the right ventricle to the lungs

Function of veins

returns deoxygenated blood from tissues to the heart

arterioles

small branches of arteries that join capillaries

venules

small veins that join capillaries

Capillaries

microscopic, one-cell-thick vessels that connect arterioles & veins

Site of gas exchange between blood and body tissues

capillaries

Lumen

internal space of a blood vessel (where blood flows)

Valves

thin, membranous leaflets in veins that prevent back-flow of blood

Antecubital fossa

shallow depression in arm anterior to / below bend of elbow; site of major veins for venipuncture

first choice vein for venipuncture

median cubital vein

second choice vein for venipuncture

cephalic vein

third choice vein for venipuncture

basilic vein

plasma makes up _____ of blood

55%

formed elements makes up ______ of blood

45%

what are formed elements composed of

RBC’s, WBC’s, & platelets

Blood type A contains what plasma antibodies

Anti-B

Blood type B contains what plasma antibodies

Anti-A

Blood type AB contains what plasma antibodies

neither anti-A or anti-B

Blood type O contains what plasma antibodies

Both anti-A and anti-B

Blood type A contains what RBC antigens

A antigen

Blood type B contains what RBC antigens

B antigen

Blood type AB contains what RBC antigens

A and B antigens

Blood type O contains what RBC antigens

neither

Rh+ indicates…

presence of D antigen

Rh- indicates…

lack of D antigen

Serum

Fluid portion of blood remaining after clotting

Does serum contain fibrinogen?

No

Plasma

Fluid portion of whole blood separated from the RBC’s, WBC’s, and platelets

Does plasma contain fibrinogen

Yes

Whole blood

Blood in same form as it is in bloodstream

Whole blood must be collected in an _______ tube

anticoagulant

Type A blood can receive blood from

A, O

Type B blood can receive blood from

B, O

Type AB blood can receive blood from

A, B, AB, O

Type O blood can receive blood from

O

Type A blood can donate to

A, AB

Type B blood can donate to

B, AB

Type AB blood can donate to

AB

Type O blood can donate to

A, B, AB, O

How many liters of blood are in the typical adult body

5 Liters

Hemostasis

Stoppage of bleeding after injury as a body response

Process of hemostasis

1. vasoconstriction

2. formation of primary platelet plug

3. progression to stable blood clot

4. fibrinolysis (dissolving of clot)

erthrocytes

RBC’s

leukocytes

WBC’s

thrombocytes

platelets

lifespan of RBC’s

approx. 120 days

lifespan of platelets

7-10 days

Coagulation

Conversion of a liquid into a semisolid gel (clot)

coagulation pathways

extrinsic (outside bloodstream) & intrinsic (inside bloodstream)

longest vein in the body

great saphenous vein

largest vein in the body

superior/inferior vena cava