Homeostasis

Question 1

Homeostasis

Answer 1

Ability of body to maintain a relatively stable environment regardless of external variances due to coordinated physiological mechanisms.

Question 2

Negative feedback

Answer 2

When a disturbance causes the system to switch back towards the set point

Question 3

Positive Feedback

Answer 3

When a disturbance is sensed but the integrator potentiates the signal. Has definitive end point.

Question 4

Steady State

Answer 4

Tendency of a system to maintain an internal equilibrium due to a coordinated response of its parts to stimulus. Requires energy. Parameters of steady state do not change over time.

Question 5

Equilibrium

Answer 5

Two compartments have the same amount of free energy, so there is no energy flux between them. Rate of forward reaction=rate of reverse reaction.

Question 6

Milieu Interieur

Answer 6

Interior environment that the cell makes for itself for optimal, biological function

Question 7

Physiology

Answer 7

The study of various mechanisms that maintain homeostasis

Question 8

Difference between steady state and equilibrium?

Answer 8

Steady state requires a transfer of energy and does not necessarily care if the values are equal (it is shooting for values within a given parameter). Equilibrium will not require a transfer of energy because the free energy is equal on both side.

Question 9

Homeostatic sensor

Answer 9

A receptor that detects a change in the variable.

Question 10

Controlled variable

Answer 10

Physiological parameter that is being controlled

Question 11

Integrator/comparator

Answer 11

Integration enter that analyzes data from the sensor and compared it to set point. Usually something in the CNS.

Question 12

Effector

Answer 12

Nerve pathways, hormones, cells, or tissues that carry out the response needed to restore homeostasis.

Question 13

Set point

Answer 13

“Normal” value that is predetermined but can be influenced by environmental adaptations.

Question 14

Feed Forward Control

Answer 14

Body anticipates a change in the variable before it happens and prepares the body for the change.

Question 15

4 common reasons why the set point will deviate

Answer 15

1) Changes according to your 24 hour cycle (start working night, it will readjust)
2) Environmental changes-moving to high altitude or other external environmental factors
3) Protective response when you are sick (temperature rising to minimize viral infections)
4) Aging or pathological changes-if you have a chronic illness, your body will continue to change

Question 16

Redundancy

Answer 16

Important systems may have backup plans in case they fail. The more vital the parameter, the more mechanisms that need to control it.

Question 17

Homeostatic Hierarchy

Answer 17

A hierarchy of importance where the set point of some variables may be altered in order to maintain others