Please enable JavaScript.
Coggle requires JavaScript to display documents.
Topic 5 - Homeostasis and Response - Coggle Diagram
Topic 5 - Homeostasis and Response
The Brain
Functions of Parts
Cerebral Cortex
Responsible For:
Consciousness
Intelligence
Memory
Language
Senses e.g sight, hearing
2 Hemispheres
Right controls the left
Left controls the right
Cerebellum
Responsible For:
Balance
Muscle co-ordination
Hypothalamus
Responsible For:
Regulating body temperature
Sending signals to the pituitary gland
Brain Stem
Medulla
Controls unconscious activity e.g breathing, beating of heart
The brain and spinal chord together make up the central nervous system
How Scientists Study the Brain
Studying People with Brain Damage
Electrically Stimulate Different Parts of the Brain
Scanning the Brain
CT Scans (X-Rays)
which areas of the brain are damaged
PET Scans (Radioactive Chemicals)
measuring the underlying activity
MRI Scans (Magnetic Fields)
certain parts of the brain are highlighted depending on what you do e.g see things, feel sad, listen to music
Why treating the Brain is so Difficult
wide range of things that can go wrong in the brain
tumours
trauma
mental health problems
infections
encased within our skull
surrounding brain tissue is fragile
extremely difficult to fix anything via surgery
the brain is so complex and we don't fully understand it and the underlying processes
makes it difficult to fix it with drugs and chemicals
Homeostasis
the regulation of conditions inside the body to maintain a stable internal environment, in response to both internal and external conditions
keeps everything around the right conditions
don't keep it constant, levels do fluctuate
even if our external conditions change, we can still keep our internal temperature at
37°c
Cells Need Specific Conditions to Function:
temperature
acidity
supply of glucose
supply of water
Automatic Control Systems
Change from Optimal Conditions - Sends a Signal - Reverses Change - Back to Normal Conditions
Receptors
- detect a change e.g a rise in temperature
Co-Ordination Centres
- brain or spinal chord - interpret the change and decide what needs to be done
Effectors
- things that carry out the change e.g muscles or glands
These components are in different parts of the body
Nervous System
very fast and precise electrical impulses through nerves
respond quickly
Endocrine System
releases hormones into the blood stream
travel through the whole body but only affect cells with the correct receptors
slower, longer lasting, more generalised
Automatic Control Systems
Negative Feedback
does the opposite of whatever the change was
too high - decrease
too low - increase
Example
normal temperature
--->
walk into a cold room
--->
receptors detect decrease in temperature
--->
send electrical impulses to co-ordination centre
--->
creates a useful response e.g. shivering
--->
effectors carry out response
--->
increases body temperature
--->
back to normal temperature
--->
if the body then becomes too hot
--->
different set of receptors and effectors carry out responses to bring the temperature back down e.g. sweating