Biology B2 - Circulatory System (Blood)

What is blood?

a tissue

one of it's job is to act as a huge transport system.

what is the job of the red blood cell?

To carry oxygen from the lungs to all the cells in the body

describe the shape of a red blood cell

biconcave disc

what does red blood cells being shaped as binconcave discs provide ?

a large surface area for absorbing oxygen

do red blood cells have a nucleus?

no

how is having no nucleus beneficial to red blood cells

more room to carry oxygen

what is the pigment in red blood cells called?

haemoglobin

Why does haemoglobin bind to oxygen?

to become oxyhaemoglobin

where does this occur?

In the lungs

what happens in body tissues

Oxyhaemoglobin splits up into haemoglobin and oxygen to release oxygen to the cells

Function of white blood cells?

fight infections

What do some WBCs do?

change shape to gobble up unwelcome microorganisms in a process called phagocytosis

what do other wbc's do

produce antibodies to fight microorganism and antitoxins to neutralise toxins released from microorganisms

what do platelets do?

help blood clot

what are they?

small fragments of cells. no nucleus

Why is blood clotting important?

When you get a wound It prevents excessive blood loss and the entry of microorganisms (they float around waiting for accidents to happen)

what is plasma

Liquid part of blood

describe the colour of plasma

pale straw-coloured liquid

what does plasma carry?

red and white blood cells

platelets

nutrients (like glucose and amino acids)

carbon dioxide (from the organs to the lungs)

urea (from the liver to the kidneys)

hormones

proteins

antibodies and antitoxins produced by WBCs