Circulatory system Flashcards
(57 cards)
Arteries
Carry oxygenated blood away from the heart to the rest of the body
Carry deoxygenated blood away from the heart to the the lungs to become oxygenated
Veins
Carry deoxygenated blood from the rest of the body to the heart
Carry oxygenated blood from the lungs TO the heart
Capillaries
Connects arteries to veins through organs
Allows the diffusion of oxygen and glucose into the body’s cells
Diffusion of carbon dioxide from the tissue into the capillaries
Adaptations of arteries
Small lumen to keep blood pressure high
Thick muscular walls to cope with the high pressure
Elastic fibres that stretch when there is a surge of blood and recoil in between to keep blood moving
Adaptations of veins
Valves to prevent back flow of blood, because the blood now travels slowly and under lower pressure after going through capillaries
Wide lumen that allows large volume of blood to flow
Carries blood at low pressure so less muscular and thinner walls
Adaptations of capillaries
Walls one cell thick to allow diffusion of oxygen in and carbon dioxide out (smaller diffusion distance)
Dense network create a large surface area so more diffusion occurs at the same time
Blood travels very slow so more time to diffuse
Plasma
The liquid part of the blood carrying other parts of the blood
Transports dissolved substances around the body:
Digestion products from intestine to organs
Co2 from cells to breathed out
Urea from liver to urine
Platelets
Small disk shaped blood fragments
Produced in bone marrow
Forms blood clot
Join to make a scab if you get cut
Red blood cells
Contain a protein haemoglobin that binds to oxygen = oxyhemoglobin
To transport oxygen to body cells
Has no nucleus, carries oxygen
Biconcave shape for surface area increase so oxygen diffuses in and out cell rapidly
White blood cells
Produced in bone marrow and fight against pathogens that enter the body
Contains dna to encode their instructions
Angina
Heart pains
Caused by reduced blood flow to heart in veins due to build up of fat in a blood vessel
Described as pressure in chest
Coronary heart disease
Narrowed coronary arteries due to build up of plaque
Reduces flow of blood to heart muscle
Heart needs a constant flow of oxygen so this is dangerous for respiration = contraction
Heart attacks
When a coronary artery is blocked due to build up of plaque
the blood supply to part of the heart muscle is cut off.
Causes a lack of oxygen over a long period of time
That part of the heart cannot continue to contract - no oxygen for respiration that allows it to contract
Mechanical Pacemakers
A small electric device implanted in the chest to keep the heart beating at a good pace
If the natural pacemakers in the right atrium don’t function properly
Stents
A tiny tube inserted into a blocked vessel using a balloon to keep it open
Statins
Medicine that lowers cholesterol
What is different about a human circulatory system than a fish?
It is a double circulatory system
So blood under higher pressure as it goes through heart twice
Journey of blood around the whole body
The deoxygenated blood is pumped from the heart to lungs
Becomes oxygenated from the oxygen we breathe in (respiratory system)
Oxygenated blood returns to heart
Heart pumps this oxygenated blood to organs
Deoxygenated blood returns to heart
It repeats
Benefit of a double circulatory system
Because it passes through the heart twice, it can be pumped more = travel through the body and give us the oxygen we need quicker
How many chambers does the heart have?
4
What chambers of the heart are at the top?
Right atrium and left atrium
What chambers of the heart are at the bottom?
Right ventricle and left ventricle
What separates the atria and ventricles?
Valves
Journey of blood from the heart to the lungs
Vena cava delivers deoxygenated blood from body to heart
Pulmonary artery passes blood from the heart to the lungs
Blood is oxygenated
Oxygenated blood back to the heart via pulmonary vein
Aorta pumps oxygenated blood to the body
