5)Blood and Organs Flashcards
What are bloods four main components?
1) Plasma
2) Platelets
3) Red Blood Cells
4) White Blood Cells
What does plasma carry? (Six things)
1) Red and white blood cells
2) Digested food products
3) Carbon dioxide
4) Urea
5) Hormones
6) Heat energy
What are platelets?
Are small fragments of cells that help blood clot, when you damage a blood cell, the platelets clump together
Describe a red blood cell
They have a bioconcave shape to give a large surface area for absorbing and releasing oxygen
Why does a red blood cell contain haemoglobin?
Because they contain iron (which gives the blood its colour)
Why don’t red blood cells have a nuclues?
To free up space for the haemoglobin
What are the microorganisms that cause disease?
Pathogens
What are the two types of white blood cells?
- Phagocytes
- Lymphocytes
What do phagocytes do?
1) Phagocytes detect things foreign in the body e.g. pathogens , and they engulf the pathogens and digest them
2) They are non-specific, they attack anything that shouldn’t be there
What do lymphocytes do?
They produce antibodies
What are the three different type of blood cell?
1) Arteries
2) Capillaries
3) Veins
What are the arteries and what they do?
1) They carry the blood away from the heart
2) Arteries carry blood under pressure
3) There walls are thick, they contain thick layers of muscle to make them strong
4) The largest artery in the body is the aorta
What are capillaries and what do they do?
1) Arteries branch into capillaries
2) They are tiny, only one cell thick
3) They have permeable walls so substances can diffuse in and out
What are veins and what do they do?
1) These carry blood to the heart
2) Capillaries join up to form veins
3) They have valves to help keep the blood flowing in the right direction
4) The largest vein is the vena cava
How does exercise increase heart rate?
- Your muscles need more energy so you respire more
- Exercise increases the amount of CO2 in the blood, and the receptors in the aorta detect the more CO2, which sends signals to the brain
- The brain sends signals to the heart, causing it to contract more frequently
What is ‘pulmonary’ related to?
The lungs
What is ‘hepatic’ related to?
The liver
What does ‘renal’ relate to?
The kidneys
What type of organs are the kidneys?
Excretion organs
Why do kidneys have nephrons?
They are filtration units in the kidneys
What are the three things that happens to blood as they go through the nephrons?
1) Ultrafiltration
2) Reabsorption
3) Release of wastes
What are the three things that happen at ultrafiltration?
1) Blood from the renal artery flows through the glomerulus
2) A high pressure is built up which squeezes water, urea, salts and glucose out of the blood and into the Bowman’s capsule
3) Membranes in the Bowman’s capsules act like filters, so big molecules like proteins and blood cells aren’t squeezed out
What is the filtered liquid in the Bowman’s capsule called?
Glomerular filtrate
What happens at reabsorption?
1) All the glucose is reabsorbed from the proximal convoluted tube. (Active transport)
2) Sufficient salt is reabsorbed. Excess salt isn’t
3) Sufficient water is reabsorbed from the collecting duct into the bloodstream
What happens after ultrafiltration and reabsorption?
The remaining substances (including water, salt and urea) form urine. This comes out of the nephron and down to the bladder.
What is osmoregulation?
Controlling the water and salt content in the body
What is ADH?
Anti-diuretic hormone
