B5.2 Human nervous system Flashcards
What is the role of the human nervous system?
Enables humans to react to their surroundings and to coordinate their behaviour
What is the CNS?
The central nervous system, includes the brain and spinal cord.
“To summarise the order of how the human nervous system works, fill in the missing words:
a -> b -> c -> d -> e”
“a) Stimulus
b) Receptor
c) Coordinator
d) Effector
e) Response”
Name the three types of neurone.
“1. Sensory
- Relay
- Motor”
What is a synapse?
The method by which a nervous impulse crosses the gap between neurones.
Summarise in five steps how a synapse works.
- Impulse arrives at the end of neurone A, 2. Neurotransmitter is released into the synaptic gap, 3. Neurotransmitter diffuses across the synaptic gap, 4. Neurotransmitter binds to receptors on neurone B, 5. A new electrical impulse is generated in neurone B.
Why are reflex actions rapid?
They do not involve the brain, therefore no conscious thought.
What do you use reflex actions for?
Reactions to remove your body from danger.
What is the brain made up of?
Billions of interconnected neurones.
What is the CNS?
The central nervous system, includes the brain and spinal cord.
Name the three main parts of the brain
Cerebral cortex, cerebellum, medulla
Why is investigating the function of the brain difficult?
It is a complex and delicate organ.
Name two ways scientists can investigate brain function.
1.Electrically stimulating areas in a conscious patients and recording their response OR 2. Magnetic Resonance Imaging (MRI) scans.
Name the two stimuli the eye is sensitive to.
Light intensity and colour.
Name the muscle that changes the shape of the lens in the eye.
Ciliary muscle
Name the ligaments in the eye which help to change the shape of the lens.
Suspensory ligaments