In this clip we see a human brain being dissected and look at the various parts of the brain such as the top section known as the cerebrum and used for thought. Deeper down are some of the more automated functions such as our heart, the way we control our breathing and consciousness etc. On the inside of the brain we see the grey and white matter and the hypothalamus which senses the concentrations of fluids in the body – particularly the concentration of the blood. If there is too little water in the blood, a chemical message is sent through the blood to the kidneys telling them to cut down on urine production. A drink will bring the water levels back to normal and the kidneys will start producing urine again. Chemical messages in the body are called hormones – the one controlling the kidneys is called anti-diuretic hormone because it stops the kidneys making urine.

First broadcast:
20 April 2007

Students could be asked which body system the brain belongs to and which other parts of the body belong to it. They could investigate the nervous system by carrying out an investigation into response times and by comparing the nervous and endocrine system. Learners could create a table to compare the relative speed, travel medium and length of time the message lasts when the body uses different communication methods. Students could also investigate other hormones used in the body and the glands which produce them, focusing on their effects on target organs.