Topics 4-6 Flashcards
What are the four parts of the blood
Plasma red blood cells white blood cells and platelets
What are the roles of red blood cells
They contain haemoglobin to carry oxygen
Approximately how many red blood cells does every person have
20 to 30 trillion
What is the adaptions of red blood cells
They have a biconcave disk shape to increase surface area for oxygen diffusion they are small and flexible so they can squeeze through narrow capillaries they have no nucleus and no DNA
What are the roles of white blood cells
- The part of your bodies defence system
- sometimes produce antitoxins which fight the poisons made by microorganisms
What are platelets what are their roles and what adaptions do they have
They are fragments of cells with no nucleus which form blood clot’s and scabs by rushing to a cut to form a protein mache
What are plasma and what does it do
It is a straw coloured liquid that all other cells floating it carries carbon dioxide , urea and hormones
Describe arteries
They have a thick layer of muscle and elastic and a relatively small lumen they carry blood away from the heart and have thick muscle elastic and connective-tissue to take blood to the organs
Describe veins veins
They have a thin layer of muscle and elastic and the largest lumen out of the three blood vessels that carry blood back to the heart and have a relatively thin muscle
Describe capillaries
They have thin vessels the walls are only one cell thick they carry blood through the organs and tissues
What type of circulatory system do mammals have
Mammals have a double circulatory system this means the blood passes through the heart twice for everyone circuit in the body
