- Structure and role of blood
- In any circulatory system there is a liquid transporting substances from one place to another. in most animals this is blood
- What makes up blood?
- 55% of blood is plasma. this is the liquid part of the blood and is made up mostly of water. it carries dissolved substances such as urea, proteins, amino acids and carbon dioxide.
- 45% of the blood is red blood cells. these carry oxygen attatched to red pigment haemoglobin. they are a squashed shaoe in order to increase their surface area for their function.
- less than 1% of the blood is made up of white blood cells and platelets. white blood cells are a part of the immune system and fight infection. platelets are involved in blood clotting and forming scabs.
- Blood helps regilate body temperature and transfer energy around the body