Biology Flashcards
The nervous system is made up of what and where do they go
They are made of nerve cells which go to all part of the body
The body has a lot of what
Sensory receptors
Different receptors detect what
Different stimuli
When a stimulus is detected by receptors what happens
The information is converted to a nervous impulse
The nervous impulse is sent where
It is sent along sensory neurones to the CNS
Impulses travel through what
The CNS along relay neurones
The CNS sends impulses where
CNS send impulses along a motor neurone to an effector
All neurones have 4 things what are they
A cell body,dendrites,dendrons and an axon
What do dendrites and dendrons do
They carry nervous impulses towards the the cell body
What do axons do
Axons carry nervous impulses away from the cell body
Axons are surrounded by what and what does it do
It’s is surrounded by a fatty material called myelin sheath this speeds up electrical impulse
What is the function of the sensory neurone
Carries impulses from receptors to the CNS
What is the function of the motor neurone
Carries impulses from CNS to effectors
What is the function of the relay neurone
Carries impulses through the CNS
Describe the structure of a sensory neurone
A sensory neurone has one long dendron and a short axon with a cell body in the middle
What is a synapse
A synapse is where 2 neurones join together
When a electrical impulse reach a synapse what happens to the chemicals
The chemicals called neurotransmitters move across the gap
What do neurotransmitters set off
They set off a new electrical impulses in the next neurones
Why do we use reflexes than normal response
We use reflexes because they are automatic this makes them quicker than normal responses
What do reflexes help us do and give an example
They help to stop injuring yours e.g moving your hand away from a hot iron
What is a reflex arc
A reflex arc is the info in a reflex from receptor to effector
Where do neurones in reflex arcs go to
Neurones in reflex arcs go to the spinal cord or through an unconscious part of the brain
What are the 5 steps of how a reflex arc works
1) Something will sting you detected by sensory neurones
2) Impulses are sent along a sensory neurone to CNS
3) In the CNS, relay neurones passes the impulses from sensory to motor neurone
4) Impulses are sent along the motor neurone to effector
5) The effector here is a muscle. Contracts to move your hand away
