The Cardiovascular System Flashcards
What is the function of the cardiovascular system?
Transporting oxygen, nutrients, hormones, and cellular waste products throughout the body.
Pumping blood around the body to get oxygen to organs, muscles and tissue in need of oxygen for energy (ATP).
What is the cardiovascular system?
The cardiovascular system consists of the heart, blood vessels, and the approximately 5 liters of blood that the blood vessels transport.
What does the cardiac cycle involve?
It involves the heart filling with blood and then pumping this to the rest of the body via the arterial system.
How long does it take to complete a heart beat?
Just under one second
What are the stages of the cardiac cycle?
Stage 1- atrial diastole
Stage 2- ventricular diastole
Stage 3- atrial systole
Stage 4- ventricular systole
What happens in stage 1 of the cardiac cycle?
The atria fill with blood returning from two key areas: the body and the lungs.
The valves remain shut.
What happens in stage 2 of the cardiac cycle?
The bicuspid and tricuspid valves open because of the pressure build-up in the atria; blood flows into the ventricles and the valves shut again.
What happens in stage 3 of the cardiac cycle?
The atria contract and blood is forced into the ventricles and pressure increases to become greater than that in the aorta and pulmonary artery.
What happens in stage 4 of the cardiac cycle?
The semilunar valves (pulmonary valve and aortic valve at the top of the heart) open and the ventricles contract, forcing blood into the aorta to move to the rest of the body or into the pulmonary artery to go to the lungs.
What is stroke volume
How much blood is squeezed out of the heart into the aorta each time it beats.
What is heart rate?
How many times your heart beats per minute.
What is cardiac output?
It is the amount of blood pumped out of the heart per minute.
What is the equation to work out cardiac output?
Cardiac output= stroke volume x heart rate
Q= SV x HR
What happens to our CO, SV and HR during exercise?
As we begin to exercise our HR goes up and so does our SV – therefore our CO increases.
Comparing trained and untrained individuals
As we train our HR does not increase as much as our ability to pump blood around our body is better (our SV is better).
Untrained= beats more! but pushes less blood out Trained= beats less because it pushes out more blood.
How much blood is in your body?
5-6 Litres for males
4-5 Litres for females
What happens when water is lost from the body?
When water is lost form the body (sweat), it is lost from the blood (plasma), the blood then becomes more viscous which then it is therefore harder to pump around the body.
Explain the redirection of blood flow.
When we exercise our body redirects blood flow to where it needs to go, so to our working muscles. This also means it is redirected away from our intestinal tract and non essential organs.
What is blood composed of?
•Red blood are produced in bone marrow and contain hemoglobin, which
carries oxygen to body tissues and muscles.
•White blood cells fight infection. They are produced in bone marrow,
lymph tissue and the spleen.
•Platelets are cells that help form blood clots to stop bleeding.
They are produced in bone marrow.
•Blood plasma carries nutrients and also removes waste products.
•Plasma is 90% water and contains fibrinogen, which assists platelets in blood clotting.
What are the functions of blood?
- Transportation of gases, fuels, and minerals
- Protection against infection and dehydration
- Maintaining the body’s state of equilibrium (homeostasis) via enzyme and hormone regulation
Measuring blood pressure and HR.
We measure blood pressure by measuring the force that is exerted by the blood against the blood vessel walls.
As blood is pumped by the heart the pressure in the arteries increases and decreases.
When blood is pumped into the aorta (ready to go around the body) it is the greatest pressure – systole.
It is the lowest pressure during ventricular diastole – when the heart relaxes and fills with blood.
Blood pressure typically is 120/80.
With 120= systole and 80= diastole
What are blood vessels?
Blood vessels make up the vascular network through which all blood flows to all parts of the body.
What is the function of the respiratory system?
The respiratory system provides oxygen to the body’s cells whilst removing carbon dioxide.
What do the airways consist of?
The airways includes, the nose, mouth, pharynx, larynx, trachea, bronchi, and bronchioles which carries air between the lungs and the body’s exterior.