#85 The human nervous system
The human nervous system is made up of two parts:
- Central nervous system (CNS) - brain and spinal cord: role of coordination
- Peripheral nervous system - nerves: connect all parts of the body to the CNS.
Sense organs are linked to the peripheral nervous system. They are groups of receptor cells responding to specific stimuli: light, sound, touch, temperature and chemicals. When exposed to a stimulus they generate an electrical impulse which passes along peripheral nerves to the CNS, triggering a response.
Peripheral nerves contain sensory and motor neurones (nerve cells).
Peripheral nerves contain sensory and motor neurones (nerve cells).
Motor and sensory neurones are covered with a myelin sheath, which insulates the neurone to make transmission of the impulse more efficient.
The cytoplasm (mainly axon and dendron) is elongated to transmit the impulse for long distances.
The cytoplasm (mainly axon and dendron) is elongated to transmit the impulse for long distances.
Fun fact: The human nervous system runs on electrical impulses that travel close to the speed of light.
Sample question and answer
Sample question and answer
Question Figure above shows a type of neurone. Name this type of neurone and state a reason for your choice. [ 2 marks]
Answer Name: motor neurone.
Reason: It has a cell body, the cell body is at the and of the cell.
Video: The Human Nervous System
Answer Name: motor neurone.
Reason: It has a cell body, the cell body is at the and of the cell.
Video: The Human Nervous System
Video: The Spinal Cord
Video: Human body Nervour System