The heart

Cells, tissues and organs

• A group of the same type of specialised cells forms a tissue (e.g. a muscles tissue is made of muscle cells)
• An organ contains several different tissues working together to carry out a particular function in the body
• The heart is an organ that pumps blood to the lungs and around the body

The structure and function of the heart

• Blood coming fom the tissues is low in oxygen (deoxygenated) 
• It is pumped by the heart to the lungs where the haemoglobin in red blood cells picks up oxygen and the blood becomes oxygenated 
• This oxygenated blood returns to the heart and is pumped around the body to the tissues and cells

• The left and right sides of the heart work together, filling and emptying at the same time
• However, to explain the the different parts of the heart…