Cardiovascular system Flashcards
What are the 4 entry and exit routes
- Superior and inferior cava
- Pulmonary artery
- Pulmonary vein
- Aorta
Superior and inferior vena cava
Carries deoxygenated blood into the heart from the head, neck, arms, and chest (superior) and the legs, feet and organs in the abdomen and pelvis (inferior)
Pulmonary artery
Delivers deoxygenated blood from the heart to the lungs
Pulmonary veins
Returns oxygenated blood from the lungs to the heart
Aorta
Delivers oxygenated blood to the body for respiration to occur
4 chambers of the heart
- Right atrium
- Right ventricle
- Left atrium
- Left ventricle
Right atrium
Deoxygenated blood enters from the vena cava
Right ventricle
Deoxygenated blood enters from the right atrium and is forced up the pulmonary artery to the lungs
Left atrium
Oxygenated blood enters form the pulmonary veins
Left ventricle
Oxygenated blood enters from the left atrium and is forced up the aorta to the body
Pathway of blood
How does the heart stop the backflow of blood
Valves
4 key valves
1.Tricuspid valves
2. Bicuspid valves
3. Aortic valves
4. Pulmonary valves
Atrio-ventricular valves
- Tricuspid valves
- Bicuspid valves
What causes the heart valves to open and shut
Pressure exerted on valves
What are the 3 main layers of the heart
1.Epicardium
2. Myocardium
3. Endocardium
Epicardium
Serves as lubricative outer covering
Myocardium
Provides muscular contractions that eject blood from the heart chambers
Endocardium
Serves as protective inner lining of the chambers and valves
Contraction of the myocardium
Cardiac or myocardial muscle
What does the myocardium thickness vary in size
Depending on the amount of stress put on a specific part of the heart
Left ventricular hypertrophy
Requirements of the left ventricle to pump blood to the systemic circulation
Electrical activity of the heart
Myocardial cells are unique as they can spontaneously depolarise and conduct electrical signals in specific directions throughout the heart
Intrinsic control of electrical activity
Cardiac conduction system