Human Body

Research on the human body specialising in the function of the heart.
Definitions:
Unicellular: living organism made up from 1 cell. e.g. protozoa and bacteria.
Multicellular: living organisms comprising of many cells. e.g. plants, animals and humans.
-Multicellular organisms have a device that gives the cells specific functions. This organisation allows a cell to grow as different tissue in a complex living organism. E.g. Muscle, lung, heart and liver tissue.
The cells work can be organised into levels:
Cells→Tissues→organs→Systems→organism
Cells which make up the human body undergo reactions that can change the energy in a food into energy that the body or cell can use or store.
Red blood cells carry oxygen to all parts of the body
White blood cells protect the body against disease.
Plasma carries food and waste around the body
Blood platelets make up the blood clot if you cut yourself.
Arteries carry blood away from the heart to the organs, such as the lungs, kidneys and liver. As well as tissues such as skin and muscles. They have a thick elastic wall to withstand greater pressures.
Capillaries are one cell thick and are close to the body cells and allow oxygen and nutrients to pass out and into the cell while waste and carbon dioxide pass back in to be carried away.
Veins transport blood to the heart. The blood is at a relatively low pressure so they have thinner walls than arteries, and non-return valves that stop blood from flowing back.
Blood flows through the body as:
Heart→Arteries→Capillaries→Veins→Heart
Systems in the Human body:
Circulatory
Nervous
Endocrine
Respiratory
Digestive
Skeletal
Excretory
Reproductive

The Circulatory System:
The circulatory system is made up of two main organs, the heart and blood vessels/ veins, arteries and capillaries. The main function of this system is to transport blood around the body in order to supply cells with oxygen and food and to take away carbon dioxide and other wastes.
Blood...