Homeostasis

Question 1

Define homeostasis

Answer 1

The maintenance of a stable environment while adjusting to changing external conditions

Question 2

Why is homeostasis important

Answer 2

Ensures regulated variables in the internal environment are maintained within a range of values compatible to life

Question 3

What is negative feedback

Answer 3

Planned corrective behaviour of any system which brings it back to baseline whenever it moves away from baseline

Question 4

Describe thermoregulation as a negative feedback mechanism

Answer 4

Thermoreceptors detect an change in core temperature and send signals to the control centre (hypothalamus), these signals are passed to the sweat gland and blood vessels to decrease body temp or blood vessels and muscles to increase temp

Question 5

Describe a generic homeostatic regulatory system

Answer 5

Stimulus in external environment causes change in regulated variable ,this is detected by sensor, signal to control centre, signal to effector, effector response to regulate variable in internal environment

Question 6

What are feedforward mechanisms of homeostasis

Answer 6

Feedforward mechanisms c,abuse changes in the controlled variables (e.g cardiac output, ventilation) in anticipation of imminent demand to reduce the movement of the regulated variable out of it’s normal range

Question 7

What are afferent fibres

Answer 7

Send signals to the CNS

Question 8

What are efferent fibres

Answer 8

carry signals from the CNS

Question 9

What are the 2 communication systems of the body

Answer 9

The endocrine system and the nervous system

Question 10

What are control variables in homeostasis

Answer 10

Variables that can be altered in order to maintain the regulated variables

Question 11

How are disturbances in homeostasis implicated in disease

Answer 11

Impaired ability to detect an imbalance by receptors, fail at control centre or impaired effector response e.g diabetes