Plasma
- Plasma is a straw coloured liquid which the other components of the blood are suspended within
- Plasma is important for the transport of many substances including:
- Carbon dioxide - the waste product of respiration, dissolved in the plasma as hydrogencarbonate ions and transported from respiring cells to the lungs
- Digested food and mineral ions - dissolved particles absorbed from the small intestine and delivered to requiring cells around the body
- Urea - the waste substance produced in the breakdown of proteins by the liver. Urea is dissolved in the plasma and transported to the kidneys
- Hormones - chemical messengers released into the blood from the endocrine organs (glands) and delivered to target tissues/organs of the body
- Heat energy - created in respiration (an exothermic reaction), heat energy is transferred to cooler parts of the body or to the skin where heat can be lost
