2. Homeostasis pt1 Flashcards

1
Q

Define homeostasis

A

Homeostasis is the regulation of the internal conditions of a cell or organism to maintain optimum conditions for function in response to internal & external changes
(Maintains optimum conditions for enzyme action and all cell functions)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What do we control and why in our internal environment?

A
  • Temperature (for correct enzyme activity)
  • blood glucose concentration (for constant energy supply)
  • water levels (to control osmosis and chemical reactions)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are the 3 components of an effective control system and what do they do?

A
  1. Receptors, to detect the change in conditions
  2. Coordination’s centres, to process the information
  3. Effectors, to bring about the correct response
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What’s the change in the environment called?

A

Stimulus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What do we call the specialised nerve endings that detect the stimuli?

A

Receptors

And when grouped together form a sense organ

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

List 7 of your receptors

A
  • eyes
  • nose
  • ears
  • tongue
  • skin
  • muscles
  • joints
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Describe the type of receptor your eye has?

A

Receptors for light

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Describe the type of receptor your nose has?

A

Receptors for chemicals forming smell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Describe the type of receptor your ears has?

A

For sound and detecting changes in position (balance)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Describe the type of receptor your tongue has?

A

Receptors for chemicals forming taste

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Describe the type of receptor your skin has?

A

Receptors for touch, pressure, pain and temperature

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Describe the type of receptor your muscles and joints have?

A

Receptors for changes in position

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the name of the specialised cells in the nervous system?

A

Neurones (which work in groups called nerves)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What does the nervous system do?

A

It enables the body to respond to changes in the environment to trigger the appropriate response

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Describe how a response in coordinated through the neurones

A
  1. Once the receptor detects the stimulus, it sends a nerve impulse along a sensory neurones
  2. This cell takes the impulse towards the central nervous system
  3. The CNS can then coordinate an effective response
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What’s the central nervous system made up of?

A

The brain and spinal cord

17
Q

How would the neurones respond to the change?

A
  1. Once the brain/spinal cord has determined an appropriate response, it sends another nerve impulse out along a motor neurone
  2. This takes the impulse to an effector organ, which carries out the response
  3. This organ can either be a muscle, that contracts/relaxes or a gland that’s triggered to secrete hormones as part of the endocrine system
18
Q

Name all 5 of the main parts of coordinating a response

A
  1. Receptor
  2. Sensory neurone
  3. Coordinator (CNS)
  4. Motor neurone
  5. Effector
19
Q

Define a reflex

A

A reflex is a fast, automatic response that occurs without conscious thought
They control basic body functions such as breathing and digestion and help you avoid harm or danger

20
Q

Explain how a reflex occurs

A
  • The sequence of events is the same as other responses but only 1 neurone is use in the CNS instead of hundreds
  • this is called a relay neurone, which connects the sensory neurone to the motor neurone through the spinal cord (sometimes in the unconscious part of the brain)
21
Q

Explain the purpose of the reflex arc

A
  • As it bypasses the brain it reduces the time between the stimulus and response
  • This minimises damage caused by stressful stimulus
  • the reflex arc will send another impulse to the conscious brain so you’re aware, but only after the reflex action has happened
22
Q

What’s the junction between each neurone called?

A

Synapse

23
Q

Explain how synapses work

A
  • 2 neurones aren’t connected, so to transmit a nerve impulse, the neurone realises a chemical into the gap
  • the chemical diffuses across the gap
  • binds the receptors on the next neurone
24
Q

Explain the brain

A

The brain controls complex behaviour. It’s made up of billions of interconnected neurones that receive sensory inputs from your receptors (sensory neurones deliver impulses), and then coordinate the appropriate response through the effectors (motor neurones deliver impulses)
And it has different regions that carry out different functions

25
Q

What are 5 parts of the brain?

A
  • cerebral cortex
  • cerebellum
  • medulla
  • pituitary gland
  • hypothalamus
26
Q

What does the cerebral cortex do?

A

Conscious
Intelligence
Memory
Language

27
Q

What does the cerebellum do?

A

Coordinating muscles

Balance

28
Q

What does the medulla do?

A

Unconscious activities

Eg. Heartbeat, breathing, digestion

29
Q

What does the pituitary gland do?

A

Secrets hormones

30
Q

What does the hypothalamus do?

A

Controls homeostatic functions

Eg. Temperature