B7 OCR Blood 21st century science GCSE

Hope it helps and don't forget to rate!

HideShow resource information

Parts of the blood

Red blood cells - carry oxygen around the body through a reversable  reaction between haemogolbin and oxygen to form oxyhaemogolbin . A red blood cell contains iron in its centre and can make bonds with 4 oxygens the reaction with CO ( carbonmonoxide is not reversable and this is why it is dangerous to humans and it makes the cell unable to carry oxygen around the body- many many of these in the blood

White blood cells- fight pathogens ( things that cause disease) by engulfing them or by firing out antibodies to make it in active - more often than not both of these processes happen to  a pathogen. Phagocytes engulf and digest through the process of phagocytosis. Lymphocytes have a big nucleus compared to their size and contain information/ memory of passes infections on how to make antibodies to attach on to the antigens of a pathogen. Very few in the blood compared to red blood cells

platelets - form scabs when you get cut enable a chemical reaction

Plasma- is a straw coloured liquid that transports things like hormones around the body and contains water 

1 of 2

Blood groups

You have groups A( 40%),B(10%),O(45%) and AB(5%) (of people)  and the alleles for A and B are condominate and O is reccesive. When blood transfusions happen they must make sure that a compaterble blood type is given O is a universal donar and AB IS A UNIVERAL REECIPIENT becuase it has both antigens and no anti bosies in the plasma to trgger clotting with other blood types . O is a universal donor because they have no antigens which would trigger clotting with other blood types.

you have the opposite antibody to the blood type that you have 

Antigens are on the red blood cells and the antibodies travel in the plasma

2 of 2


No comments have yet been made

Similar Biology resources:

See all Biology resources »See all Circulation resources »