Homeostasis

Question 1

What is Homeostasis?

Answer 1

The regulation of constant internal environment to maintain equilibrium in the body

Question 2

What things do Homeostasis involve?

Answer 2

• Water levels
• Blood glucose
• Body temperature
• Removes toxins
• Blood pressure
• pH levels

Question 3

What is negative feedback?

Answer 3

• negative feedback is the mechanism used to maintain equalibrium in the body. It does this by opposing a change that deviates from normal.

Question 4

Negative feedback cycle?

Answer 4

1) - Stimulus -produces a change in variable
2) Change detected by a receptor
3) Input - information sent to control center
4) Output - information sent to effector
5) Response of effecter, returns to homeostais

Question 5

What is optimal internal environment?

Answer 5

Temperature: 35C/37C
Heart rate: 60-100bpm
Oxygen saturation: 98%
Respiratory rate: 14-20 rpm
Blood glucose: 3.5 6 mmols
Blood pressure: 120/80

Question 6

What organs does it involve?

Answer 6

Hypothalamus 
Pituitary gland
Liver
Kidney
Muscle
Pancreas

Question 7

Why is homeostasis important?

Answer 7

If homeostasis isn’t used in the body it can cause things such as:
-Hypothermia -Pyrexia (high temp)
-Bradycardia (slower heart rate) - Tachycardia (high
heart rate)
-Hypoxia (low oxygen levels) - Hypercapnia (too
much CO2)
-Hypotension - Hypertension
(High blood
pressure) (low blood pressure)

Question 8

True or False: The maintenance of a constant environment in the body is called Homeostasis?

Answer 8

True

Question 9

True or False: negative feedback is the mechanism by which the body maintains conditions with particular limits?

Answer 9

True

Question 10

True or false: Glucagon is the hormone that increases the amount of glucose in the blood?

Answer 10

True - secreted by pancreas

Question 11

True or false: The liver produces insulin?

Answer 11

False - The pancreas produces insulin

Question 12

True or False: Insulin is a hormone that increases the amount of glucose in the blood?

Answer 12

• False

Question 13

True or False: Hyperglycemia is when blood glucose levels are too low?

Answer 13

False, Hyperglycemia is when blood glucose levels are too HIGH.

Question 14

What is Thermoregulation?

Answer 14

• Thermoregulation is how our body maintains body temperature, meaning the body will react if it gets too hot or cold.

Question 15

What part of the brain does Thermoregulation involve?

Answer 15

-involves receptors linked to the hypothalamus

Question 16

What is Vasodilation?

Answer 16

• This is when the body temperature is too hot, blood vessels near the skin get wider to allow warm blood to flow near the surface and lose heat, which cools you down.

Question 17

What is Vasoconstriction?

Answer 17

• When the body gets too cold, blood vessels near the surface of the skin get smaller, this means less blood flows to the surface, keeping heat closer to your body core.

Question 18

What does the body do if body temp is too high?

Answer 18

• Vasodilation
• Muscles controlling the hairs on the skin relax, causing hair to lie flat
• Sweat is secreted from sweat glands, as it evaporates it cools you down

Question 19

What does the body do if body temp is too cold?

Answer 19

• Vasoconstriction
• Erector muscles contract, pulling hairs up on end, this traps warm air close to the skin
• Shivering also warms us up, muscles generate more heat through respiration.
• sweat glands no longer secrete sweat

Question 20

What are 2 homeostasis mechanisms?

Answer 20

• Thermoregulation

- Osmoregulation