Introduction to Physiology

Question 1

What does intrinsic control mean?

Answer 1

A control that is inherent in an organ.

Question 2

What does extrinsic control mean?

Answer 2

A regulatory mechanism initiated outside an organ. E.g. nervous and endocrine systems.

Question 3

Name three types of physiological control systems.

Answer 3

Feedforward control, negative feedback control and positive feedback control.

Question 4

What is the difference between positive feedback control and negative feedback control?

Answer 4

Positive feedback control amplifies an initial change VS negative feedback control opposes an initial change.

Question 5

Define homeostasis.

Answer 5

Homeostasis is the maintenance of steady states within the body by coordinated physiological systems.

Question 6

Is homeostasis important?

Answer 6

Homeostasis is essential for life as variables within the body need to be tightly regulated within a narrow range. Could cause death if not maintained.

Question 7

Describe the pathway of a general negative feedback control response.

Answer 7

Deviation in regulated variable- detected by sensor- informs control centre- instructs effectors to - carry out compensatory response - resulting in restoration of regulated variable- negative feedback system shut off.

Question 8

Give three examples of variables regulated by negative feedback.

Answer 8

Any 3: Core body temperature, mean arterial blood pressure, blood glucose, blood H+ concentration and blood gases.