B2 - Organisation Part 2 Flashcards
What is the function of the trachea?
Carries air to/from the lungs
What is the function of the bronchioles?
Carries air to/from the alveoli
What is the function of the alveoli?
Site of gas exchange in the lungs
What is the function of the capillaries?
Allows gas exchange between blood and alveoli
Connects arteries and veins
Supply food and oxygen and take away waste like CO^2
What is the function of the right ventricle?
Pumps deoxygenated blood into the lungs to take in oxygen
What is the purpose of the left ventricle?
Pumps oxygenated blood around all other organs of the body
What is the function of the artery and how is it adapted ( 4 marks)
Carries blood away from the heart
Artery walls are strong and elastic - can carry blood under high pressure
Thick layers of muscle to make them strong and elastic fibres to allow them to stretch and spring back
What is the function of the vein and how is it adapted#
How do veins prevent backflow of blood
Carries blood into the heart
Large lumen to help blood flow despite the lower pressure
Thin walls - carries blood under low pressure
They have valves
What is the function of the capillary and how is it adapted
Supply food and oxygen so substances can diffuse in and out
Connect arteries and veins together
Walls are one cell thick - can carry blood under very low pressure, increases the rate of diffusion by decreasing distance
Permeable walls, so substances can diffuse in and out
What is the purpose of circulatory system?
Carries oxygen and other useful substances to tissues and removes waste substances
How does the double circulatory system work?
One pathway carries blood from the heart to the lungs
One pathway carries blood from the heart to the tissues
What are the four parts of the blood
Plasma
Red blood cell
White blood cell
Platelets
What is the function of the plasma and red blood cell
Transports CO2, hormones and waste
Carries oxygen
What is the function of the white blood cell how is it adapted to do this function (5 marks)
Defends against infection
Can change shape for phagocytosis
Produce antibodies to fight microorganisms
Produces antitoxins to neutralise any toxins produced by the microorganisms
Clump together to form blood clots no
How to calculate rate of blood flow and units
volume of blood/number of minutes
ml/min
How are red blood cells adapted for its function
(3 marks)
Biconcave disk for large surface area for absorbing oxygen
No nucleus, allows more room for carrying oxygen
Contains haemoglobin, can combine with oxygen in the lungs and release it in body tissues
Why do platelets blood clot
Stop blood pouring out and stop microorganisms getting in
What causes CHD and how can it be treated
Build up of fatty materials in coronary arteries
Stents - Statins
What causes CHD and how can it be treated
Build up of fatty materials in coronary arteries
Stents - Statins
What causes heart failure and how can it be treated
Heart can not pump enough blood
Artificial heart
Donor heart
What causes a fault in the valve and how can it be treated
Blood doesn’t flow normally
Valve replacement
Pros and cons of stents
(4 marks)
Pros: Effective for a long time and the recovery time from the surgery is relatively quick
Cons: Risk of complications during the operation such as an heart attack and risk of infection from surgery
Risk of patient developing blood clot near the stent (thrombosis)
How are statins used to treat CHD
(2 marks)
Drug that reduces the amount of ‘bad’ cholesterol in the bloodstream. Slows down rate of fatty deposits forming
What are the advantages of using statins ( 3 marks)
Pros:
By reducing the amount of ‘bad’ cholesterol in the blood statins can reduce the risk of strokes, CHD and heart attacks
Can increase the amount of beneficial cholesterol in blood, this type removes the amount of ‘bad’ cholesterol from the blood
Statins may prevent some other diseases
What are the disadvantage of using statins (3 marks)
Long term drug that must be taken regularly, risk patient may forget them
Negative side effects - headaches
Some serious ones like kidney failure, liver damage and memory loss
The effect of statins is not instant, and it takes time for their effect to kick in
What can a faulty valve lead to ( 2 marks)
Valve tissue stiffens - won’t open properly
Function of platelets and does it have a nucleus
Clump together to form blood clots no
How are stents used to treat CHD
( 4 marks)
Tubes inserted inside arteries, keeps them open, making sure blood can pass through to the heart muscles, keeping the persons heart beating and alive
What is the function of the coronary arteries
Branch of aorta and surround the surface of the heart making sure that it gets all the oxygenated blood
What parts of the heart pump deoxygenated blood
Vena cava
Pulmonary Artery
What parts of the heart pumps oxygenated blood
Aorta
Pulmonary Vein
Explain how the heart uses the four chambers to pump blood around ( 5 marks)
Blood flows into the two atria from the vena cava and pulmonary vein
Atria contract pushing blood into ventricles
Ventricles contract forcing blood into the pulmonary artery and aorta and out of the heart
Blood then flows to the organs through arteries and returns through veins
Atria fills again and whole cycle starts over
What controls the natural resting heart rate?
A group of cells located in the right atrium (pacemaker cells).
What are artificial pacemakers used for?
Electrical devices
used to correct irregularities in the heart rate.
Order of the heart
vena cava
Pulmonary artery
Aorta
Pulmonary vein
What does a lack of platelets lead
Can cause excessive bleeding and bruising
What does a leaky valve lead to ( 2 marks)
Blood flows in both direction rather than just forward - blood doesn’t circulate as effectively as normal
What is the function of the aorta
Carries blood away from the heart to organs
What is the function of the pulmonary artery
Carries blood away to the heart
