Cardiovascular Flashcards
1
Q
cardiovascular system
A
- heart propels blood to and from body tissues via 2 types of blood vessels, arteries and veins
- arteries and veins directly entering and leaving the heart are called great vessels
2
Q
arteries
A
- blood vessels that carry blood away from heart
- ~oxygenated
3
Q
veins
A
- blood vessels that carry blood back to heart
- ~deoxygenated
4
Q
characteristics of heart
A
- blood flow through heart is unidirectional because of 4 valves within heart
- capillary bed is one cell thick, where all exchange occurs
- heart is functionally two side-by-side pumps that work at same rate and pump same volume of blood
- one pump direct deoxygenated blood to lungs, one pump directs oxygenated blood to most body tissues
5
Q
functions of heart
A
- heart generates blood pressure through alternate cycles of heart walls contraction (systole) and relaxation (diastole)
6
Q
blood pressure
A
- force of blood pushing against inside walls of blood vessels
- min blood pressure is essential to circulate blood throughout body
- higher on contraction phase
- 120/80 is normal
7
Q
2 circulations of cardiovascular system
A
1) pulmonary
2) systemic
8
Q
pulmonary circulation
A
- right side of heart and pulmonary arteries and veins
- conveys deoxygenated blood to the lungs for oxygenation and back to left side of heart
9
Q
systemic circulation
A
- left side of heart and arteries and veins
- conveys oxygenated blood to body tissues and deoxygenated blood back to right side of heart
10
Q
vessels of pulmonary circulation
A
- pulmonary veins
- pulmonary arteries
- right atrium
- right ventricle
11
Q
vessels of systemic circulation
A
- left atrium
- left ventricle
- aorta to systemic arteries
- systemic veins
12
Q
apex and base
A
- apex: inferior
- base: superior
13
Q
pericardium
A
- hear is enclosed in tough sac called pericardium
- restricts heart movement so it only moves slightly in thorax
- protects heart
14
Q
two parts of pericardium
A
1) fibrous pericardium
2) serous pericardium
15
Q
fibrous pericardium
A
- tick outer covering of tough, dense connective tissue
16
Q
serous pericardium
A
- closer to heart
- composed of two layers
- parietal layer: outer surface
- visceral layer: inner surface
- in between is pericardial cavity filled with fluid
17
Q
anatomy of heart wall
A
- 3 layers
1) epicardium
2) myocardium
3) endocardium
18
Q
epicardium
A
- consists of visceral layer of serous pericardium and areolar connective tissue
- outer
19
Q
myocardium
A
- cardiac muscles
- thickest layer
- middle
20
Q
endocardium
A
- internal surface of heat chambers and external surface of heart valves
- where blood is running
- inner
21
Q
structure of cardiac muscle cells
A
- branches
- single, central nucleus
- striated (thin actin and thick myosin)
- intercalated discs at junctions
- functional syncytium (when on contracts, they all contract)
22
Q
cardiac vortex dn functional syncitium
A
- atrial muscles ranged in figure 8 around smaller atria
- ventricular muscles are wrapped around and between larger ventricles
23
Q
external heart anatomy
A
- 4 hollow chambers: 2 smaller and superior atria and 2 larger inferior ventricles
- inferoanterior borders of atria form muscular extension called auricles
atria and ventricles are separate from each other by a groove called coronary sulcus - anterior and posterior interventricular sulki are between right and left ventricles and run from coronary sulcus toward apex
- grooves are for blood vessels to sit in so they don’t hit against pericardium and lose pressure
24
Q
4 chambers of heart
A
1) right atrium
2) right ventricle
3) left atrium
4) left ventricle
25
4 valves of heart
1) right atrioventricular (tricuspid)
2) pulmonary semilunar
3) left atrioventricular (bicuspid o mitral)
4) aortic semilunar
26
right atrium
- receives venous blood from heart, muscles, and systemic circulation
27
3 veins that drain into right atrium
1) superior vena cava
2) inferior vena cava
3) coronary sinus (drains deoxygenated blood out of heart)
28
right atrioventricular valve
- deoxygenated blood flows from right atrium to right ventricle through this
- forced closed when right ventricle begins to contract, preventing blood back flow into right atrium
29
right ventricle
- receives deoxygenated blood from right atrium
- inter ventricular septum forms thick wall between right and left ventricles
- inner wall of each ventricle displays large, irregular muscular ridges called trabecular carneae, to move blood to have better chance of picking up more oxygen
30
papillary muscles
- 3 cone shapes muscle projections in right ventricle
- anchor thin strands of strong connective tissue made of collagen fibers called chordae tendonae
- cordae tendonae attach to 3 cusps of right atrioventricular valve
- cusps are triangular flaps that hang down into ventricle
- cordae tendonae prevents cusps from prolapsing into right atrium when right ventricle contracts
31
conus arterioles of right ventricle
- at superior end, smooth area
- beyond is pulmonary semilunar valve which marks end of ventricle and beginning of pulmonary trunk
- deoxygenated blood is sent to lungs
32
semilunar valves
- 2: pulmonary and aortic
- in roof of right and left ventricles
- composed of 3 thin half-moon-shaped, pocket like semilunar cusps
- no cordae tendonae or papillary muscles
- when ventricles contract, blood pushes cusps against arterial trunks
- when ventricles relax, some blood flows back toward ventricles, enters pockets of cusps and forces them towards midline, closing the valve
-
33
left atrium
- oxygenated blood from lungs travels through pulmonary veins to here
- separated from left ventricle by left atrioventricular valve
- valve has 2 triangular cusps
- valve is forced shut when left ventricle contracts
34
left ventricle
- wall is 3x thicker than right because you need to produce a greater pressure wave to fight gravity and circulate blood
- pumps blood to entire body except lungs
- aortic semilunar valve at roof which marks end of left ventricle and beginning of aorta
35
aorta
- largest vessel in body
3 regions: ascending aorta, aortic arch, and descending aorta
- descending aorta supplies blood to lower limbs and viscera
36
3 branches or aortic arch
1) brachiocephalic trunk: right head and upper limbs, has right common carotid and right subclavian
2) left common carotid: left head
3) left subclavian: left upper limb
37
coronary circulation
- right and left coronary arteries travel in coronary sulcus and supply heart wall with oxygen and nutrients
- coronary arteries are only branches given off by ascending aorta
- openings are aortic sinuses
38
coronary veins
- venous return of blood from heart wall muscles occur through 3 major veins
1) great cardiac vein: anterior interventricular artery
2) middle cardiac vein: posterior interventricular artery
3) small cardiac vein: close to marginal artery
- all drain into coronary sinus that drains into right atrium
39
anatomy of blood vessels
- arteries, capillaries, and veins
- arteries carry blood away from hear and become progressively smaller as they branch into arterioles and then capillaries
- veins return blood to hearts and become progressively larger as they exit capillaries and merge into venues and veins as they get closer to heart
40
3 blood vessel tunics
1) tunica externa
2) tunica media
3) tunica intima
41
tunica externa
- connective tissue that helps anchor blood vessel to an organ
- larger blood vessels require their own blood supply
- smaller arteries that supply larger are called vasa vasorum which run through this
42
tunica media
- comprised of circularly arranged smooth muscle
- sympathetic input causes smooth muscle to contract resulting in vasoconstriction
- parasympathetic input results in vasodilation
43
tunica intima
- composed of an endothelium (simple squamous epithelium lining inside or arteries and veins)
and a sub endothelial layer of areolar connective tissue
44
types of arteries
- elastic arteries
- muscular arteries
- arterioles
45
elastic arteries
- largest, biggest lumen, thickest walls
- huge volume of elastic fibers
- elastic fibers allows arteries to stretch under increased pressure generated by bloodlfow
- branch into muscular arteries
46
muscular arteries
- possess elastic fibres in 2 concentric rings between 3 tunic
1) internal elastic lamina: separates tunia intima and media
2) external elastic lamina: separates tunica media and externa
47
arterioles
- smaller, thinner lumen
- less than 6 cells layers of smooth muscle in tunica medis
- sympathetic innervation to muscle fibre cells of tunica media causes vasoconstriction resulting in elevated blood pressure
- parasympathetic innervation cause vasodilation and lower blood pressure
- only vessels capable of vasoconstriction and vasodilation
48
capillaries
- smallest of all blood vessles
- diameter slightly larger than erythrocytes
- wall is only tunica intima (single epithelium layer)
- only type of blood vessel where metabolic exchange can occur between blood and cells outside of bloodstream
49
types of capillaries
1) continuous
2) fenestrated
3) sinusoid
50
continuous capillaries
- most common
- endothelial cells form a continuous and complete lining aided by presence of tight junction
- skin, lungs, muscles
51
fenestrated capillaries
- endothelial cells possess small holes to allow fluid exchange between blood and interstitial fluid
- kidney, small intestine
52
sinusoid capillaries
- have big gaps between endothelial cells that promote transport of large molecules and cells to and from the blood
- liver, spleen
53
venules
- smallest veins
- companion vessels with arterioles
- smallest are located at end of capillary bed and called post capillary venules
- merge to form veins
54
veins
- larger than venues
- smaller and medium sized travel within muscular arteries
- large travel with elastic arteries
- BP in veins is too low to overcome forces of gravity and possess valves
- as skeletal muscles contra they help to pump blood towards heart (skeletal muscle pump)
- at rest, body veins old ~60% of body blood
- they function as blood reservoirs
