B10 - The Nervous System Flashcards
Why do we have senses?
So we can respond to our environment and benefit our survival.
Why does responding to our environment benefit our survival?
Prevents damage to our bodies.
Avoid predators.
Find food.
Seek shelter.
Find mates to reproduce.
What does homeostasis mean?
Regulations of internal conditions.
In response to internal and external changes.
To maintain optimal conditions for enzyme action and all cell functions.
What are three examples of regulations of internal conditions?
Body temperature.
Water content of the blood.
Blood glucose concentration.
What are 4 examples of in response to internal and external changes?
Water consumption.
Physical activity.
Carbohydrates in diet.
External temperature.
What are 3 examples of maintaining optimal conditions for enzyme action and all cell functions?
Enzymes denaturing if they get too hot.
Osmosis of water out of cells causing them to shrivel and not function.
Osmosis of water into cells so they burst and no longer function.
What is the order of the nervous system?
Stimulus - receptor - coordinator - effector - response
What is a stimulus?
An environmental change
What is a receptor?
Cells, tissues or organs that detect changes in the environment.
What is a coordinator?
Central nervous system that coordinates which effector to activate.
What is the effector?
Muscles or glands which caused responses.
What is a response?
A behaviour caused by effectors in reaction to the stimulus.
What are neurones?
Specialised cells which carry electrical impulses from receptors to effectors.
What is a sensory neurone?
Send electrical impulses from receptors to the coordination centres.
What is a relay neurone?
Sends electrical impulses to different parts of coordination centre.
What is a motor neurone?
Sends impulses from coordination centre to the effectors.
What is a conscious response?
a response to a stimulus which involved the conscious part of the brain.
Give examples if when conscious response is used?
controlling heart rate
blinking
closing eye’s iris
What is a synapse?
gaps between neurones where a transmitter substance is released.
What is a reflex response?
a fast, automatic response to a stimulus that bypasses the conscious part of the brain.
they protect the body from harm.