homeostasis

Question 1

define homeostasis

Answer 1

maintain stable and balances internal environment

Question 2

what is the fluid inside/outside of a cell called?

Answer 2

intracellular/extracellular

Question 3

through what methods does the body react to counteract the disturbance?

Answer 3

NFB, nerve impulses:

nerve impulses and hormones counteract the deviation from the balanced state

Question 4

examples of controlled conditions and what is the name of the disruption of the condition?

Answer 4

• blood glucose levels
  -blood pressure levels
• name of distruption= stimulus

Question 5

define what a feedback cycle is:

Answer 5

monitores and changes the body

Question 6

what are the three main components of a feedback system:

Answer 6

1. receptor
2. control centre
3. effector

Question 7

For receptor: Define,pathway,examples

Answer 7

1. monitors the changes in the controlled conditions and sends info to the control centre
2. Afferent pathway
   3.changes in temperature

Question 8

For control centre:
Define,pathway,examples

Answer 8

1. receives info from the receptor and sets a range of values where the controlled conditions should be at
2. Efferent pathway
3. hypothalamus

Question 9

For effector:
briefly explain its process with an example

Answer 9

receives output from the control centre and makes a response, an example is a drop in temperature, the control centre sends impulses to skeletal muscle ( to shiver) increasing its temperature

Question 10

what is the difference between efferent and afferent pathways?
SA
ME

Answer 10

SA= sensory (afferent) body to brain
ME=Motor (efferent). brain to body

Question 11

when does the response return to homeostasis?

Answer 11

when it brings the controlled condition back to normal

Question 12

Describe briefly a detailed feedback cycle.

Answer 12

1. stimulus (this interferes with homeostasis by increasing or decreasing controlled conditions)
2. controlled condition ( monitored by receptors)
3. receptors (input, sends nerve impulses and chemical signals to control centre)
4. control centre (receives input and and sends it to effector)
   5.effector(output, in changes the response based on info given)
   response( changes controlled condition to normal i.e homeostasis)

Question 13

define negative feedback

Answer 13

counteracts and reverses changes in controlled conditions

Question 14

what happens when body temp is below/above normal?

Answer 14

1. stimulus= is the low temp
2. receptor= skin detects low temp
3. control centre=brain- hypothalamus brings it to 37
   4.effector= blood vessels in the skin constrict and sweat glands don’t work and skeletal muscle shiver to make heat

-vice versa for high temp

Question 15

explain in steps the NFB in blood pressure and include baroreceptors.

Answer 15

1. stimulus
2. controlled condition
3. receptors (baroreceptors)
4. control centre(brain)
5. effector( heart and blood vessels)
6. response( decrease in heart rate and dilation in blood vessels AKA VASODILATION)

Question 16

whats the difference between hypotension and hypertension?

Answer 16

HYPO= low blood pressure
HYPER= high blood pressure

Question 17

Define positive feedback

Answer 17

amplification of deviated controlled conditions

Question 18

examples of PFB

Answer 18

• childbirth
• blood clotting
• milk let down reflex from breast

Question 19

explain the process of blood clotting

Answer 19

1. tear in blood vessel wall
2. clotting happens as platelets go to site and emit chemicals
3. due to this chemical more platelets go to site
4. clotting continues until the tear is sealed and forms a new clot

Question 20

main difference between NFB and PFB

Answer 20

NFB= restores and maintains stability in controlled condition
PFB= amplifies the deviation of controlled conditions

Question 21

outline the PFB in childbirth

Answer 21

1.initial contraction=release of oxytocin (hormone that starts the uterus contraction)
2.PFB= as the uterus contracts, the babys head is pushed against the cervix causing stretching and pressure
3. this constant pressure causes more oxytocin release
4. cycle goes on with amplification on a contraction each time until a cut of point which is usually when the child is out

Question 22

define both disease and disorder

Answer 22

disorder= abnormal function
disease= illness that can be seen through symptoms and signs