Anatomy & Physiology - Cardiovascular system Flashcards
function of the vena cava?
Deoxygenated blood back to right atrium
Function of the pulmonary artery?
Deoxygenated blood from right atrium to lungs
Function of the pulmonary vein?
Oxygenated blood to left atrium
Function of the aorta?
Oxygenated blood from left ventricle to rest of body
4 types of valves?
- Bicuspid valve
- Tricuspid valve
- Semi-lunar pulmonary valve
- Semi-lunar aortic valve
Positive about the left ventricle?
Strongest chamber of heart as must pump blood the greatest distance. Walls are thicker and stronger as more force resistant
Order of blood flow?
- Right atrium
- Tricuspid valve
- Right ventricle
- Pulmonary artery
- Lungs
- Pulmonary vein
- Left atrium
- Bicuspid valve
- Left ventricle
- Aorta
Explain cardiac conduction?
- starts in the sinoatrial node (SA node) hearts pacemaker. Stimulates and contracts aorta
- Pulse travels down into atrioventricular node (AN node). Short delay (0-1 second) to allow atria to contact
- ventricles fill with blood
- impulse travels through bundle of his
- down the purkinje fibers (left + right branches of ventricle walls)
- Ventricle systole occurs / ventricle contacts
What is the heart?
Heart is myogenic - produces it’s own impulse
Neural control of the heart - sympathetic
During exercise, this system increases heart rate and cardiac output by releasing adrenaline and norepinephrine into the heart
Neural control of the heart - parasympathetic
During rest this system decreases heart rate and cardiac output, through the vagus nerve, by releasing acetylcholine into the heart
what do sympathetic nerve impulse do?
They are sent to stimulate the SAN more frequently and there is a decrease in parasympathetic nerve impulses (vagus nerves), so the heart rate increases
what are the 3 receptors?
- Chemoreceptors
- Baroreceptors
- Proprioceptors
What do chemoreceptors detect?
Detects chemical changes within the heart. 1 - Blood acidity + pH. 2 - CO2
what is the chemoreceptors reaction?
- Co2 levels increase + HR increase
- pH levels drop (more acidic), HR increase