Heart Structure Flashcards
What is the name of the muscle found in the heart?
- Cardiac muscle.
What is the “cardiac muscle?”
- Walls of heart have thick, muscular layer = cardiac muscle.
What are the two unique properties of the cardiac muscle?
- Never fatigues (as long as it has supply of oxygen/ glucose.)
- Myogenic: it can contract/ relax without nervous/ hormonal stimulation.
What do coronary arteries do? Where are they found? What happens if these become blocked?
- Supply cardiac muscle with oxygenated blood.
- Branch off from the aorta.
- Cardiac muscle won’t receive oxygen, won’t be able to respire/ cells will die –> heart attack.
What are the four chambers of the heart?
- Right atrium
- Left atrium.
- Right ventricle.
- Left ventricle.
Structural features of the atria chambers in heart.
- Thinner muscular walls, do not need to contract as hard as ventricles, not pumping blood very far - only to ventricles.
- Elastic walls that stretch when blood enters.
Structural features of the left ventricle.
- Pumps blood to the body. Needs to be higher pressure to ensure blood reaches all cells in the body.
- Much thicker muscular wall, compared to right ventricle, to enable larger contractions of the muscle to create higher pressure.
Structural features of the right ventricle.
- Pumps blood to the lungs. Needs to be at low pressure to prevent damage to capilaries in lungs and so blood flows slowly to allow time for gas exchange.
- Thinner muscular wall in comparison to left ventricle.
What are the two MAJOR veins of the heart? What do they do?
- Vena cava (superior/ inferior): carries deoxygenated blood from body into right atrium.
- Pulmonary vein: carries oxygenated blood from lungs to the left atrium.
What are the two MAJOR arteries of the heart? What do they do?
- Pulmonary artery: Carries deoxyenated blood from right ventricle to the lungs to become oxygenated.
- Aorta: carries oxygenated blood from the left ventricle to rest of the body.
What are the two sets of valves found in the heart?
- Atriventricular valves.
- Semi-lunar valves.
What are atriventricular valves?
- Valves between atria and ventricles.
- Bicuspid: left side.
- Tricuspid: right side.
Where are semi-lunar valves found in the heart?
-Aorta
- Pulmonary artery.
-Between the left ventricle and aorta OR between the right ventricle and pulmonary artery
What do valves do? How do they carry out this function?
- Prevent backflow of blood/ maintain unidirectional flow of blood.
- Open when pressure is higher behind the valve.
- Close when pressure is higher in front of the valve.
What is the septum?
- Section of cardiac muscle, separating oxygenated and deoxygenated blood.
- Maintains high concentration of oxygen in oxygenated blood to maintain cocentration gradient to enable diffusion at respiring cells.
In the capilary surrounding the alveoli, where is the pressure of the blood the highest and why?
- Where blood ENTERS the capilary.
- Because the blood is enterring straight from the heart/ left ventricle.
