Blood & Vessels Flashcards
What are 2 adaptations of red blood cells?
- They don’t have a nucleus to allow for more haemoglobin
- Shaped like a bio cave disk which gives it a larger surface area for absorbed oxygen.
What do white blood cells do?
Defend us from pathogens via phagocytosis, antibodies and antitoxins.
What are platelets?
Small fragments of cells that perform clotting and stop blood pouring out and stop microorganisms from getting in.
What is plasma?
A fluid that makes the blood watery so it flows. Carries rbc,wbc,platelets, hormones, waste etc.
How much blood does the average adult have?
5L
What are the 2 options to replace lost blood?
Artificial blood or transfusions
What are the advantages and disadvantages of artificial blood?
It is salt water that is donated so adds volume but doesn’t contain rbc, expensive.
What are the advantages and disadvantages of blood transfusions?
It is real blood so comes with rbc unkind artificial blood. Goes against some religious beliefs, risk of allergic reaction.
What do arteries do?
Carry blood away from the heart
What do capillaries do?
Exchange nutrients
What do veins do?
Carry blood back to the heart
What are some adaptations of arteries?
They are strong because the blood pressure is high and they have thick muscle/elastic tissue. Narrow lumen
What are some qualities of capillaries?
Really small, exchanges substances with cells, takeaway waste products, permeable to allow for diffusion, low blood pressure so the flow is smaller, allowing time for exchange
What are some qualities of veins?
Large, big lumens, thin walls with thin layers of elastic fibres and smooth muscle. Low blood pressure so the walls don’t need to be strong. Have valves to prevent back flow.
How do you calculate the rate of blood flow?
Amount of blood / time taken
