P2 - 5.1 Homeostatis

Question 1

What is homeostasis

Answer 1

Maintaining a stable internal environment

Question 2

What conditions do animal cells need to function correctly

Answer 2

• it cannot be too hot or too cold
• it cannot be too acidic or to alkaline
• good supply of glucose
• good supply of water

Question 3

How does our body make sure our cells dont reach conditions where they wouldn’t function properly

Answer 3

Our bodies regulate everything to make sure everything is kept around the right levels

Question 4

What 2 things does our body not regulate (only happens in small bounds)

Answer 4

Temperature
Glucose levels

• these often fluctuate but only in small bounds

Question 5

What is the definition of homeostasis

Answer 5

Homeostasis is the regulation of conditions inside the body to maintain a stable internal environment, in response to both internal and external conditions

Question 6

What kinds of external conditions can affect our internal conditions

Answer 6

• temperature being too hot
• temperature being too cold

Question 7

What temperature should the human body be roughly

Answer 7

37°C

Question 8

What is the name of the function our bodies do to change from optimal conditions to convert into a signal to reverse the change

Answer 8

Automatic control

Question 9

What is automatic control in homeostasis

Answer 9

When there is a change from optimal conditions, a signal can be sent in order to reverse the change and change our levels back to normal

Question 10

What are optimal conditions

Answer 10

Conditions that are outside of the conditions we are used to

Question 11

What are the 3 systems in automatic control

Answer 11

• receptors
• coordination centres
• effectors

Question 12

What is a receptor

Answer 12

Receptors detect a change such an an increase in temperature

Question 13

What is the coordination centre

Answer 13

The coordination centre is made up of your brain and spinal chord, they interpret the change and then decide what needs to be done about it

Question 14

What is an effector

Answer 14

An effector carries out a change such as releasing hormones or contracting muscles

Question 15

What are the 2 main types of effectors

Answer 15

Glands
Muscles

Question 16

In an automatic control system what might the effector, gland do

Answer 16

Release hormones

Question 17

In an automatic control system what might the effector, muscle do

Answer 17

The muscle might contract

Question 18

What 2 types of systems are linked to automatic control in homeostasis

Answer 18

Nervous system
Endocrine system

Question 19

What is the nervous system

Answer 19

The nervous system is subconscious, very fast and precise. It sends electrical impulses through nerves to send information to respond to things very quickly to avoid the body getting harmed

Question 20

What is the endocrine system

Answer 20

Hormones (that are small chemicals) that are released into the bloodstream. They can travel around the entire body but only will affect certain cells that have the correct receptors.

The endocrine system is much slower, longer lasting and more generalised in comparison to the nervous system

Question 21

What are some similarities and differences of the nervous system and endocrine system

Answer 21

Similarities:
- both respond to things in the body for example homeostasis

Differences:
- NS is very fast whereas ES is very slow
- NS is via electrical impulses whereas ES is through bloodstream
- NS is precise whereas ES is more generalised
- NS is specific to certain body part etc brain, spinal chord whereas ES can travel around entire body

Question 22

What is the name of the mechanism that triggers an automatic control in homeostasis

Answer 22

Negative feedback

Question 23

What is negative feedback in homeostasis

Answer 23

Whenever a level of something gets too high ie. Glucose levels in blood, negative feedback decreases it again to return the levels to normal

Question 24

What happens if the amount of glucose levels in our blood is to too low?

Answer 24

Negative feedback increases it to return it to normal

Question 25

What happens if the amount of glucose levels in our blood is to too high?

Answer 25

Negative feedback decreases it back to normal

Question 26

Scenario:

You have walked into a room that is very cold.

Explain how your body will respond to this.

Answer 26

Your receptors in your skin will detect the external conditions have a low temperature. The receptors carry this electrical impulse to sensory neurone to relay neurone in spinal chord which informs brain and then decides the response which this electrical impulse travels through motor neurone to effector such as muscle that will contract to make us shiver to heat our bodies back to the normal temperature

Question 27

Scenario:

You have walked into a room that is very hot.

Explain how your body will respond to this.

Answer 27

Receptors in your skin detect the rise in temperature from external conditions and sends signal through sensory neurone to coordination centre the relay neurone then takes electrical impulse to motor neurone and the effector causes us to sweat to release heat and return body temperature back to normal

Question 28

Why does the body need to maintain optimal conditions?

Answer 28

For optimal enzyme action and cell function

Question 29

Which of these are considered ‘internal conditions’?
1) Room temperature
2) Blood glucose concentration
3) Blood pH

Answer 29

2) Blood glucose concentration
3) Blood pH

Question 30

Which of these are considered ‘external conditions’?
1) Blood oxygen concentration
2) Room temperature
3) The amount of fluids your drink

Answer 30

2) Room temperature
3) The amount of fluids your drink