The Cardiovascular System

?
  • Created by: Jade
  • Created on: 16-01-21 13:46
What are the three main components of the cardiovascular system?
The heart

The blood vessels

The blood within the vessels
1 of 58
What is the main function of the cardiovascular system?
Transportation of substances through the blood, to and from cells.
2 of 58
What encloses the heart?
A sac called the pericardium.
The superficial part of this sac is referred to as the fibrous pericardium. Deep to the fibrous pericardium is the two-layered serous pericardium (the parietal pericardium and the visceral pericardium (aka - the epicardium))
3 of 58
What is the function of the Fibrous pericardium?
It helps protect the heart and anchors it to surrounding structures, such as the diaphragm and sternum.
4 of 58
What are the three layers of the heart walls?
The outer epicardium (the visceral pericardium)

The myocardium

The innermost endocardium
5 of 58
Which layer of the heart walls contracts?
The myocardium - composed of cardiac muscle.
6 of 58
What are the four chambers of the heart?
Right and left atrium

Right and left ventricles
7 of 58
What are the four heart valves?
Atrioventricular valves (prevent backflow into the atria when ventricles contract) - bicuspid valve and tricuspid valve.
Semilunar valves - pulmonary valve and aortic valve.
8 of 58
What is the pathway of blood through the heart?
Superior/inferior vena cava -> right atrium -> tricuspid valve -> right ventricle -> pulmonary valve -> pulmonary arteries -> lungs (the blood is oxygenated) -> pulmonary veins -> left atrium -> left ventricle -> aorta -> rest of body.
9 of 58
How does the heart function as a double pump?
Arteries carry blood away from the heart and veins carry blood towards it.

The right side is the pulmonary circuit pump, the left side is the pulmonary circulation.
10 of 58
What is the function of the pulmonary circuit pump?
It receives oxygen-poor blood from the veins through the superior and inferior vena cava and pumps it out through the pulmonary trunk.
11 of 58
What does the pulmonary trunk split into?
The right and left pulmonary arteries - carry blood to the lungs, where oxygen is picked up and carbon dioxide is unloaded.
12 of 58
What is the function of the pulmonary circulation?
To carry blood to the lungs for gas exchange and then return it to the heart.
13 of 58
What is the function of the the intrinsic conduction system (nodal system)?
This system causes heart muscle depolarization in only one direction- from the atria to the ventricles.

It sets the basic rhythm of the heart.
14 of 58
What is the approximate contraction rate enforced by the intrinsic conduction system?
75 bpm
15 of 58
What are the components of the intrinsic conduction system?
The sinoatrial (SA) node

The atrioventricular (AV) node

The bundle of His

The right and left bundle branches

The Purkinje fibers
16 of 58
Where is the SA node located?
The right atrium
17 of 58
What is the function of the SA node?
As it has the highest rate of depolarisation, it starts each heartbeat and sets the pace for the whole heart.
18 of 58
Where is the AV node located?
The junction of the atria and the ventricles.
19 of 58
What occurs at the AV node?
The impulse spreads from the SA node through the atria to the AV node, and then the atria contract.
At the AV node, the impulse is delayed briefly to give the atria time to finish contracting.
20 of 58
What is the cardiac cycle?
The sequence of events that occurs in one complete beat of the heart.
21 of 58
What are the phases of the cardiac cycle?
Atrial diastole (ventricular filling)

Atrial systole

Isovolumetric contraction

Ventricular systole (ejection phase)

Isovolumetric relaxation
22 of 58
What occurs during the atrial diastole phase?
The heart is completely relaxed. Pressure in the heart is low, the AV valves are open, and blood is flowing passively through the atria into the ventricles. The semilunar valves are closed.
23 of 58
What occurs during the atrial systole phase?
The ventricles remain in diastole as the atria contract, forcing blood into the ventricles to complete ventricular filling.
24 of 58
What occurs during the isovolumetric contraction phase?
Atrial systole ends, and ventricular systole begins. The initial rise in intraventricular pressure closes the AV valves, preventing backflow of blood into the atria. The ventricles are completely closed chambers.
25 of 58
What occurs during the ventricular systole phase?
The ven­tricles ­contract, causing the intraventricular pressure to surpass the pressure in the major arteries leaving the heart. The semilunar valves open and blood is ejected from the ventricles. The atria are relaxed and filling with blood.
26 of 58
What occurs during the isovolumetric relaxation phase?
The pressure in the ventricles falls below that in the major arteries, and the semilunar valves close to prevent backflow into the ventricles. The ventricles are completely closed chambers and intraventricular pressure decreases.
27 of 58
When does the cardiac cycle repeat?
When atrial pressure is above intraventricular pressure, the AV valves open, and the cycle repeats.
28 of 58
What is cardiac output?
The amount of blood pumped out by each side of the heart in 1 minute.

It is the product of the heart rate and the stroke volume. (HR x SV = CO)
29 of 58
What is stroke volume?
The volume of blood pumped out by a ventricle with each heartbeat.
30 of 58
What are the three tunics (layers) of blood vessel walls?
The tunica intima

The tunica media

The tunica externia
31 of 58
What is the function of the tunica intima?
Decreases friction as blood flows through the vessel lumen (interior).
32 of 58
What is the function of the tunica media?
To change the diameter of the vessels.
As the vessels constrict/dilate, blood pressure increases/decreases.
33 of 58
What is the function of the tunica externia?
To support and protect the vessels.
34 of 58
What is the largest artery in the body?
The aorta
35 of 58
What are the arterial branches of the ascending aorta?
The only branches of the ascending aorta are the right coronary artery and left coronary artery, which serve the heart.
36 of 58
What is the first arterial branch of the aortic arch?
The brachiocephalic trunk - splits into the R. common carotid artery , which further branches into the R. internal and R. external carotid arteries, and the R. subclavian artery.
37 of 58
What is the second arterial branch of the aortic arch?
The L. common carotid artery - it divides, forming the L. internal carotid (which serves the brain), and the L. external carotid (which serves the skin and muscles of the head and neck).
38 of 58
What is the third arterial branch of the aortic arch?
The L. subclavian artery — branches into the vertebral artery (which serves part of the brain), the axillary artery and the brachial artery (which supplies the arm), and the radial artery and ulnar artery (which serve the forearm).
39 of 58
What are the main arteries?
Carotid - to neck and head
Coronary - to the heart
Hepatic - to the liver and stomach
Mesenteric - to the intestines
Renal - to the kidneys
Femoral - to the legs
40 of 58
Where do veins drain to?
All veins superior to the diaphragm drain into the superior vena cava, and those inferior to the ­ diaphragm drain into the inferior vena cava.

Both venae cavae enter the right atrium of the heart.
41 of 58
Name the veins draining into the superior vena cava.
The radial vein, the ulnar vein, the brachial vein, the cephalic vein, the basilic vein, the median, the cubital vein, the subclavian vein, the external jugular vein, the vertebral vein, the internal jugular vein and the brachiocephalic vein.
42 of 58
Which veins drain the arm?
The radial and ulnar vein drain the forearm.
They unite to form the brachial vein which drains the arm and empties into the axillary vein. The cephalic vein drains the lateral part of the arm into the axillary vein.
43 of 58
Which veins drain the arm? (Continued...)
The basilic vein drains the medial aspect of the arm and empties into the brachial vein. The basilic and cephalic veins are joined by the median cubital vein.
44 of 58
Which vein is often chosen as the site for withdrawing blood?
The median cubital vein
45 of 58
Where does the subclavian vein receive venous blood from?
The arm through the axillary vein and from the skin and muscles of the head through the external jugular vein.
46 of 58
What does the vertebral vein drain?
The posterior part of the head.
47 of 58
Where does the internal jugular vein drain?
The dural sinuses of the brain.
48 of 58
What occurs in the brachiocephalic veins?
They receive venous drainage from the subclavian, vertebral, and internal jugular veins on their respective sides. The brachiocephalic veins join to form the superior vena cava, which enters the heart.
49 of 58
Name the veins draining into the inferior vena cava.
The tribal veins, the fibular vein, the popliteal vein, the femoral vein, the external and internal iliac veins, common iliac veins, the great saphenous vein, the gonadal veins, the renal veins, the hepatic portal vein and the hepatic veins.
50 of 58
Which veins drain the leg?
The anterior and posterior tibial veins and the fibular vein drain the calf and foot. The posterior tibial vein becomes the popliteal vein at the knee and then the femoral vein in the thigh. The great saphenous veins empty into the femoral vein.
51 of 58
When is a common iliac vein formed?
By the union of the external iliac vein and the internal iliac vein which drain the pelvis.
52 of 58
What do the gonadal veins drain?
The ovaries and testicles; they empty into the renal veins.
53 of 58
What does the hepatic portal vein drain?
The digestive tract organs.
54 of 58
Which vein drains the liver?
The hepatic vein.
55 of 58
What is systolic pressure?
The pressure in the arteries at the peak of ventricular contraction.
56 of 58
What is diastolic pressure?
The pressure when the ventricles are relaxing.
57 of 58
What is blood pressure measured in?
Millimeters of mercury (mmHg).
58 of 58

Other cards in this set

Card 2

Front

What is the main function of the cardiovascular system?

Back

Transportation of substances through the blood, to and from cells.

Card 3

Front

What encloses the heart?

Back

Preview of the front of card 3

Card 4

Front

What is the function of the Fibrous pericardium?

Back

Preview of the front of card 4

Card 5

Front

What are the three layers of the heart walls?

Back

Preview of the front of card 5
View more cards

Comments

No comments have yet been made

Similar Nursing resources:

See all Nursing resources »See all Anatomy and Physiology resources »