The nervous system- PAPER 2 Flashcards
What does the nervous system mean for us?
Means that humans can react to their surroundings and coordinate behaviour.
Name 2 types of effector
Muscles (contract) and glands (secrete hormones)
What is in the Central Nervous System? (CNS) in humans and mammals.
Brain and Spinal chord.
Mammals have sensory neurones and motor neurones.
What is a synapase? How does it work?
The connection between two neurones, the nerve signal is transferred by chemicals which diffuse across the gap. They then set off an electrical signal in the next neurone.
What is a reflex?
A rapid, automatic response to a stimuli that doesn’t involve the conscious part of the brain. It reduces the chance of being injured.
What is a reflex arc?
The passage of information in a reflex.
The neurones in reflex arcs go through where?
Spinal cord or through an unconscious part of the brain.
Describe the pathway of the reflex from stimulus to effector.
The stimulus is detected by receptors which send impulses along a sensory neurone to the CNS. The impulse is transferred to a relay neurone, it is then transferred to a motor neurone and travels along it to the effector.
What is the cerebellum?
The part of the brain responsible for muscle coordination.
How does an MRI scan help see what’s wrong?
It produces a very detailed picture of the brain structures. Scientists use it to find out what areas of the brain are active when people are doing certain things e.g. listening to music.
How do you electrically stimulate the brain and why?
By pushing a tiny electrode into the tissue and giving it a small zap of electricity. By doing this you get an idea of what that part does e.g. when a certain part of the brain ( the motor area) is stimulated it causes muscle contraction and movement.
