Anatomy And Physiology - The Cardiovascular System Flashcards
What is the structure of the heart?
Divided into 4 chambers the left and the right atria and left and right ventricles.
Valves to ensure the blood flows in one direction.
Septum is a wall of muscle that divides the left and right sides of the heart.
What is the blood flow in the heart?
- The de-oxygenated blood from the body enters the heart through the vena cava and flows into the right atrium.
- The right atrium contracts, sending blood to the right ventricle through the tricuspid valve.
- The right ventricle contracts, pumping blood to the lungs via the pulmonary artery.
- in the lungs, the blood picks up oxygen becoming oxygenated, returns to the left atrium of the heart via the pulmonary veins.
- The blood then moves into the left ventricle through the mitral valve, and is pumped to the body through the aorta, the largest artery in the body.
What is heart rate?
Refers to the number of heartbeats per minute while the body is at rest. A normal adult resting heart rate is 70 beats per minute.
What is meant by blood pressure?
The pressure of blood against the walls of the arteries, and is typically lower at rest than during exercise.
What are arteries?
Carry blood away from the heart. Most arteries carry oxygenated blood with the exception of the pulmonary.
What are veins?
Carry blood to the heart. Most veins carry deoxygenated blood from the tissues back to the heart with the exceptions being the pulmonary vein.
What are capillaries?
Connect arteries to veins and facilitate the exchange of oxygen, carbon dioxide, and other substances between blood and tissues.
What happens to the heart rate during exercise?
As exercise intensity increases, heart rate also increases to meet the rising demand for oxygen by the working muscles.
What is stroke volume?
Stroke volume refers to the amount of blood ejected by the left ventricle of the heart during one contraction or heartbeat.
What happens to stroke volume during exercise?
Stroke volume typically increases during the initial stages of exercise.
At higher intensities, stroke volume plateaus. The mechanism involves more blood returning to the heart (preload), causing the heart muscle fibres to stretch and contract with more force, thus ejecting more blood.
What is cardiac output?
Cardiac output is the volume of blood ejected by the heart per minute and is calculated as heart rate multiplied by stroke volume.
What will happen to cardiac output during exercise?
During exercise of increasing intensity, cardiac output initially increases due to the combined increase in both heart rate and stroke volume.
What are the average values resting and exercise for stroke volume?
70ml
150ml
What are the average values for resting and during exercise cardiac output?
5 l/m
15 l/m
What are cardiovascular drift?
When heart rate continues to increase while stroke volume decreases.
What is EPOC?
Excess post-exercise oxygen consumption
Uses more oxygen than is available, and EPOC serves to repay this oxygen debt.
What is the alactic stage of recovery?
Fast component of EPOC, and occurs immediately after exercise and lasts 2-3 minutes.
Resynthesises ATP and restores phosphocreatine.
Excess oxygen is consumed to replenish energy stores.
Helps clear myoglobin of oxygen debt.
What is the lactic stage of recovery?
Is the slow component of EPOC and occurs after the alactic stage and lasts up to several hours.
Removes lactic acid: though oxidation
Supports oxygen delivery and CO2 removal.
Replenishes energy stores
Gradually lowers body temp and restores pH balance.
