Blood

Question 1

What are the 4 main components to blood

Answer 1

Red blood cells,White blood cells,Platelets, Plasma

Question 2

Red blood cells

Answer 2

-are very small and have no nucleus.
-are biconcave in shape, giving a large surface area: volume ratio
-contain an iron pigment called haemoglobin which can pick up oxygen.
-When oxygen combines with haemoglobin it forms oxyhaemoglobin which is bright red.When oxygen is released to the tissues it turns purple/red
-Have a life span of around 120 days

Question 3

White blood cells

Answer 3

-are slightly larger than red blood cells
-come in many different types
-are concerned with protecting the body
-they are able to detect bacteria and then destroy them before they harm the body
-phagocytosis is when they engulf the bacteria to destroy them
-produce antibodies. These protect us from infection. They work by making the bacteria cells stick together so that it is easier to kill them and some others release toxins which neutralize the poison released by the bacteria

Question 4

Platelets

Answer 4

-tiny cell fragments
-carried around in the blood and usually do nothing
-if the blood is exposed to the air in a cut the platelets help to form a network of fibres at the cut, called a clot
-this prevents blood being lost from the cut and stops bacteria and dirt getting in
-the clot hardens to a scab. This keeps the wound clean while new skin grows.

Question 5

Plasma

Answer 5

-the liquid portion of the blood
-Yellowish in colour
-Makes up around 55% of blood volume
-Is mainly water but contains dissolved substances including:
-digested food (nutrients) o Hormones
-Wastes like carbon dioxide

Question 6

How is blood made up

Answer 6

-55% plasma
-<1% buffer coat (white blood cells and platelets)
-45% red blood cells