B3 - The Blood

Question 1

What is blood?

Answer 1

A tissue which;
sends oxygen to muscle cells
carries immunological white blood cells which carry antibodies
scabs over wounds to prevent microbe infection (coagulation)
removes carbon dioxide
supplies nutrients (glucose)
temperature control
hydraulic functions eg. penis

Question 2

What is the plasma in the blood?

Answer 2

Yellow liquid in which blood cells are suspended. It carries nutrients, glucose, hormones, carbon dioxide, minerals and amino acids.

Question 3

What is the job of the red blood cell?

Answer 3

Transports oxygen around the body. It contains haemoglobin which picks up oxygen. When carrying oxygen it becomes oxyhaemoglobin. It contains iron atoms. It prefers to irreversibly bond with carbon monoxide which forms carboxyhaemoglobin.

Question 4

What is the job of the white blood cell?

Answer 4

It makes antibodies and antitoxins which engulf and digest microbes. It is a lot larger than a red blood cell.

Question 5

What is the function of the platelets?

Answer 5

Platelets are small fragments of cells which help clot blood at cuts to make scabs.

Question 6

How are red blood cells well adapted for carrying oxygen?

Answer 6

They have no nucleus which means they have a greater surface area for oxygen

bi concave disc shape which also gives a greater surface area for oxygen

they are just slightly wider than the diameter of a capillary which means they slow down as they enter the capillary so exchange of materials is maximised.

Question 7

Describe where the blood transports carbon dioxide from and to.

Answer 7

Carbon dioxide which is produced in respiration is carried by the blood plasma. The carbon dioxide diffuses into the blood plasmas at the cells where it is made and they diffuse out of the plasma at the lungs.

Question 8

Describe where the blood transports soluble products of digestion from and to.

Answer 8

Small soluble products of digestion move out of the gut in the blood plasma. They are then carried in the plasma to the cells that require them.

Question 9

Describe where the blood transports urea from and to.

Answer 9

Urea is another waste product which is carried by the plasma which comes from the breakdown of proteins. It is removed from the plasma by the kidneys where is makes up part of urine.