Ed Biology Gcse Coursework

As a result of this research, current thinking suggests that while homeostasis controls the ‘minute-by-minute fluctuation in the environment’ , circadian rhythms control the body’s general programming over time.In this essay, we will concentrate on two examples of homeostasis, one that occurs in humans and one which occurs in plants.Clearly, this is another example of homeostasis and it is outlined in Figure 2.

There are many examples of homeostatic control throughout the human body and in other living organisms, such as p H, pressure, and temperature.

A concept important to homeostasis is the process of feedback circuits; involving a receptor, an effector, and a control centre.

Another effect would be causing hair cells on the skin to force up their hairs, creating a trapped layer of air across the body surface.

Such effects should then cause the body temperature to rise to the optimal 37°C again, causing feedback to switch the circuit ‘off’.

A receptor is responsible for detecting a change in the body, while the effector corrects this.

The control centre organises these two together to elicit the response.

Figure 2: Blood glucose control by insulin and glucagon If the blood glucose level is too high, more insulin and less glucagon is released.

This causes cells to take in glucose from the blood, while the liver converts glucose to glycogen.

During low levels of blood glucose however, glucagon release increases, activating the breakdown of glycogen to glucose in the liver, and glucose is released into the blood.

This is a good example of negative feedback control, as the lowering of blood glucose, for example, inhibits further insulin secretion. This is because glucose activates calcium channels.