Functions Of Blood

Question 1

What are the five functions of blood?

Answer 1

Transport
Body Regulation
Exchange Of Materials With Body Tissue 
Preventing Infection
Blood Clotting

Question 2

Transport

Answer 2

Blood transports oxygen from the lungs and carbon dioxide back to the lungs.
Also transports nutrients to where they’re needed.
Waste products are transported to the liver or kidneys to be detoxified or removed from the body.
Hormones are transported from their production site to their target cells.

Question 3

Body Regulation

Answer 3

A build-up of carbon dioxide and hydrogen can cause the pH level to drop. The blood removes these elements and replaces them with oxygen.
Water balance is maintained by the blood carrying waste products to the kidneys so they can be filtered out and enable water to be distributed around the body.
Body temperature is also regulated by the blood. When it is hot outside blood vessels dilate so they are closer to the skin and heat can be lost through the skin. When temperature is low they can constrict, meaning they get smaller so that heat is kept in the body.

Question 4

Exchange Of Materials With Body Tissues

Answer 4

Blood capillaries are important in exchanging materials.
Oxygen is inhaled into the alveoli and transfers into the capillaries where it can then be distributed around the body. Carbon dioxide is brought back to the alveoli through the capillaries and is exhaled to remove it from the body.

Question 5

Preventing Infection

Answer 5

White blood cells are the key component of blood that prevents the body from infection. There are neutrophils whose purpose is to destroy bacteria by producing antibodies.
Lymphocytes are T- type cells that can destroy viruses and cancer cells.
Monocytes remove dead cells and bacteria.

Question 6

Blood Clotting

Answer 6

Platelets secrete vasoconstrictors which constrict the blood vessels, causing vascular spasms in broken blood vessels which closes them up to stop the bleeding.
Platelets then form a temporary ‘platelet plug’ by pulling together the walls of the broken blood vessel.
Once the platelet plug has been formed the platelets make blood clot at the site.