1. Components Of Cardiovascular System. Chapter 12, Fox

Front 1

Heart

Back 1

A muscular pump which creates a pressure head to push blood through blood vessels.

Front 2

Pulmonary Circuit:
1) Is supplied by which side of the heart?
2) Carries blood from where to where?
3) When is blood deoxygenated/oxygenated?

Back 2

1) Right
2) Heart to Lungs (and lungs to heart)
3) Blood entering lungs is deoxygenated. Blood leaving lungs is oxygenated.

Front 3

Systemic Circuit:
1) Is supplied by which side of the heart?
2) Carries blood from where to where?
3) When is blood deoxygenated/oxygenated?

Back 3

1) Left
2) Heart to tissues (and tissues to heart)
3) Blood entering tissues is oxygenated. Blood leaving tissues is deoxygenated.

Front 4

Tricuspid and Bicuspid Valves:
1) Are which type?
2) Are embedded in what?
3) Open when?
4) Allow blood to flow how?

Back 4

1) Atrioventricular
2) Embedded in a layer of CT btw aria and ventricles
3) Open during atrial contraction
4) Allow blood to flow only from atria into ventricles.

Front 5

Semilunar Valves:
1) Two named...
2) Are located where?
3) Open when?
4) Allow blood to flow how?

Back 5

1) Pulmonary semilunar and aortic semilunar
2) Located at the origin of the pulmonary artery and the aorta
3) Open during ventricular contraction
4) Allow blood to flow only from ventricles to arterioles.

Front 6

Contraction of <3:
1) Pushes blood where?
2) Increases or decreases pressure?

Back 6

1) Pushes blood out of heart into vasculature.
2) Increases pressure.

Front 7

Relaxation of <3:
1) Entails what?
2) Increases or decreases pressure?

Back 7

1) Allows heart to fill with blood.
2) Decreases pressure.

Front 8

What are adjacent myocardial cells joined by?

Back 8

Intercalated discs containing gap junctions.

Front 9

What is required to initiate contraction in myocardial cells? (Hint: unlike in SR)

Back 9

Extracellular Ca 2+

Front 10

1) What is required to initiate cardiac muscle contraction?
2) What contains the cells responsible for triggering contraction?
3) What are these cells called?

Back 10

1) External stimulation by somatic motor nerves.
2) SA node; sinoatrial node
3) Pacemaker or autorhythymic cells.

Front 11

1) Where is the SA node located?
2) What occurs to the cell membrane that causes the generation of a contraction?

Back 11

1) Top right atria near the superior vena cava
2) Cell membrane spontaneously depolarizes and creates AP's which are spread through adjacent myocardial cells, generating contraction.

Front 12

What happens during the repolarization of myocardial cells?

Back 12

Ca 2+ is transported out of the cells and relaxation occurs.

Front 13

How does the length of a myocardial cell AP compare to the length of an AP in a skeletal muscle cell?

Back 13

It's much longer. In fact, the contraction is nearly as long as the duration of the AP itself.

Front 14

T of F: Myocardial cells are refractory during almost their entire contraction.

Back 14

True

Front 15

T or F: Summation of contraction can occur in myocardial cells.

Back 15

False. This is how tetanus in cardiac muscle is prevented.

Front 16

T or F: Pacemaker cells have gap junctions.

Back 16

False! Pacemaker cells themselves do not have gap jxns but can stimulate contraction by spontaneously generating APs.

Front 17

What is the pathway of electrical activity from the atria to the ventricles?

Back 17

Atria --> bundle of His --> bundle branches along interventricular septum --> Purkinje fibers --> Ventricles

Front 18

Where in the pathway of electrical activity is the rate of conduction greatly reduced? What effect does this have on heart contraction?

Back 18

The AV node. This causes atrial and ventricular contraction to occur sequentially.

Front 19

What do the P, QRS, and T waves result from?

Back 19

P: atrial depolarization

QRS: atrial repolarization/ ventricular depolarization

T: ventricular repolarization

Front 20

T of F: At EDV, the ventricles are filled with blood.

Back 20

True

Front 21

What are the conditions at isovolumetric contraction?

Back 21

Ventricular depolarization.
Ventricle pressure is greater than atrial pressure.
AV valves close BUT pressure is not great enough to open semilunar valves.

Front 22

What is stroke volume?

Back 22

EDV - ESV

*ventricles eject 2/3 of blood they contain (SV)
*1/3 of initial volume remains (ESV)

Front 23

What are the conditions at isovolumetric relaxation?

Back 23

Ventricular repolarization, Ventricles begin to relax,
AV and semilunar valves are closed.

Front 24

Sympathetic nerves release ______ which triggers _____ receptors.

Back 24

Noradrenaline (norepinephrine).

Adrenergic receptors.

Front 25

Parasympathetic nerves release ______ which triggers _____ receptors.

Back 25

Acetylcholine.

Muscarinic receptors.

Front 26

Cardiac Output =

Back 26

SV x cardiac rate
(EDV - ESV) x cardiac rate

Cardiac output: the volume of blood pumped per minute by each ventricle. At rest, cardiac output = about 5.5 L/min!

Front 27

What are sympathetic nerves responsible for triggering?

Back 27

Spontaneous Depolarizations. The noradrenaline released from symp. nerves stimulates the opening of Na+ and Ca2+ channels in the pacemaker cells of the SA node.

Front 28

What are parasympathetic nerves responsible for?

Back 28

Slowing the rate of depolarization. The parasymp. vagus nerves release acetylcholine, which promotes the opening of K+ channels of pacemaker cells.

Front 29

Frank-Starling Law of the Heart:

Back 29

-The more blood volume in the ventricle before contraction, the more blood ejected during contraction.
-INTRINSIC property of the heart muscle (no external input is needed)

Front 30

T or F:
SV, Contractility, and EDV are all directly proportional.

Back 30

True.

Front 31

What sets the rate of contraction?

Back 31

The rate of depolarization in the SA node.

Front 32

What does the SA node determine?

Back 32

Heart rate.

Front 33

What does smooth muscle lack that results in it being striation-less?

Back 33

Sarcomeres.
It instead has a lattice structure.
actin > myosin.

Front 34

During smooth muscle contraction, Ca2+ diffuses through VGC into the cell. What does it then bind with?

Back 34

Calmodulin...NOT troponin C!
The Ca2+ calmodulin complex then joins with and activates myosin light chain kinase (MLCK).

Front 35

T or F: Smooth muscle contraction is slower and has a less sustained contraction than that of skeletal muscle.

Back 35

False. Smooth muscle contraction is slower and has a MORE sustained contraction than that of skeletal muscle.