Blood And Organs Flashcards
Name six things plasma transports around the body
Plasma is a pale yellow liquid which carries everything needs transporting around your body:
1) red, white blood cells and platelets
2) digested food products (like glucose and amino acids) from the gut to all the body cells
3) carbon dioxide from body cells to the lungs
4) urea from the liver to the kidneys
5) hormones, which act as chemical messengers
6) heat energy
What are platelets. What role do they play in the body
Platelets are small fragments of cells that help blood clot:
1) when you damage s blood vessel, platelets camp together to ‘plug’ the damaged area
2) this is known as blood clotting. Blood clots stop you losing too much blood and prevent microorganisms from entering the wound
3) in a clot, platelets are held together by a mesh of protein called fibrin (they also need other proteins called clotting factors to work properly)
How do phagocytes defend the body from infection
Phagocytes detect things that are foreign to the body e.g. Pathogens. They then engulf the pathogens and digest them
Phagocytes are Non - specific they attack anything that’s not meant to be there
How do lymphocytes defend the body from pathogens
Lymphocytes produce antibodies:
1) every pathogen has unique molecules called antigens on its surface.
2) when a certain white blood cell, lymphocytes, come across a foreign antigen, they will start to produce proteins called antibodies.
3) these lock on to the invading pathogens and mark them out for destruction. These antibodies are specific to that type of antigen
4) antibodies are produced rapidly and flow around the body to mark all other pathogens
5) some of these lymphocytes stay around in the blood as memory cells so it can quickly produce antibodies if you get infected again
How do vaccinations prevent infections
Vaccination involves injecting inert pathogens into the body. These cart antigens, so even though they’re harmless they still trigger an immune response - your lymphocytes produce antibodies to attack them.
Some of these lymphocytes will remain in the blood as memory cells so if love pathogens of the same type ever appear the antibodies will kill them
What are the walls of the arteries like and why
The heart pumps the blood out at high pressure so the artery walls are strong and elastic
How are the capillaries adapted to their function
Their walls are usually one cell thick. This increases the rate of diffusion by the decreasing the distance over which it happens
They have permeable walls so substances can diffusion in and out
NAme the blood vessel that joins to the right ventricle of the heart. Where does it take the blood
The deoxygenated blood moves through to the right ventricle, which pumps it to the lungs via PULMONARY ARTERY
Why does the left ventricle have a thicker wall than the right right ventricle
The left ventricle has a much thicker wall than the right ventricle. It needs more muscle be chase it has to pump blood around the whole body, whereas the right ventricle only had to pump it to the lungs
How and why does heart rate change in exercise
When you exercise your muscles need mores energy so respire more.
1) you need to get more oxygen into the cells and remove more carbon dioxide. For this to happen the blood has to flow faster, so your heart rate increases. Here’s how:
Exercise increases the amount of co2 in the blood
High levels of blood co2 are detected by receptors in the sorts and carotid artery
These receptors send signals to the brain
The brain sends signals to the heart, causing it to contract more frequently with more force
What are the names of the main blood vessels that carries blood away from the liver
Hepatic vein
What are the two main blood vessels associated with the lungs
Pulmonary artery
Pulmonary vein
What are he three main roles of the kidneys
1) removal of urea from the blood. Urea is produced in the liver from excess amino acids
2) adjustment of salt levels in the blood
3) adjustment of water content of the blood
Describe the process of ultrafiltration
1) blood from renal artery flows through the glomerulus - bundle of capillaries at the start of the nephron
2) a high pressure is built up which squeezes water, urea, salts and glucose out of the blood and into the bowmans capsule
3) memranea between the blood vessels in the glomerulus and the bowmans capsule act like filters so big molecules like proteins and blood cells are not squeezed out. They stay in the blood.
What happens in the collecting duct if the nephron
Sufficient water is reabsorbed from the collecting duct into the blood stream
