Homeostasis Machanisms

Question 1

What body systems are involved in maintaining homeostasis?

Answer 1

Nervous, endocrine, musculoskeletal, integumentary, excretory, reproductive

Question 2

What are 5 components of homeostatic systems?

Answer 2

Stimulus 
Sensor
Integrator (control centre, brain/spinal chord)
Effector (regulator)
Response

Question 3

Describe the homeostatic system in which your blood pressure increases

Answer 3

Arterial stretch receptors (sensors) detect high blood pressure change (stimulus) in arteries which signals the brain. The brain (integrator) then relays information to decrease strength of the hearts contractions (effector) and the blood pressure will decrease (response).

Question 4

Describe negative feedback and provide an example

Answer 4

restore conditions to their original state
Example: household thermostat
A change in a variable being monitored triggers control mechanism to counteract further changes

Temperature of room is cold (stimulus) me the sensor would go to the thermostat (integrator) and turn it up, which sends signals to the heater (effector) and heat is produced (response)

Question 5

Describe positive feedback and provide an example

Answer 5

reinforce changes
Less common than negative feedback
Example: birthing process

Progesterone levels drop which initiates contractions, contractions release oxytocin (keeps releasing this to positively reinforce contractions)

Another example: scrape-> scab
Body keeps sending platelets to promote blood clotting to form a scab

Question 6

What conditions do humans operate best at?

Answer 6

37 degrees body temp
0.1% blood sugar
Blood pH of 7.35

Question 7

Why is positive feedback sometimes harmful in humans?

Answer 7

Example : hemophilia

Doesn’t have clotting factor, nervous system does not send platelets when you get a cut