The Human Nervous System Flashcards
Give 3 examples of a sense organ
Eyes
Ears
Skin
What are the main parts of the CNS?
Brain
Spinal cord
How does the CNS work?
The receptor cells in the sensory organs bring the Information as electrical impulses to the sensory neurones who give it to the relay neurons in the CNS to sort out. This information is then given to the motor neurones who pass it onto the effector cells in the muscle.
What does the human nervous system contain of?
The brain
Spinal cord
Peripheral nerves
Where are receptor cells found?
In the sensory organs
Explain a sensory neurone
A sensory neuron carries information to the CNS from the receptor cells in the form of electrical impulses
Explain a relay neuron
Relay neurones are involved in transferring information from sensory neuron to the motor neurones
Why is a relay neuron highly branched?
It is highly branched to allow connections with a greater number of neurons
Explain a motor neurone
Motor neurones are involved in transmitting messages from the Relay neurones to the effector cells found in muscles and glands
What is a reflex action?
A reflex action is a very quick response that usually happens when danger is sensed by the receptor cells
Why is a reflex action so rapid?
A reflex action or a reflexed Ark is extremely rapid because the only consists of three neurones
What is a synapsis?
A synapsis is a microscopic gap between neurons
What is the form of the nerve impulse transported across the synapses?
The nerve impulse is transported across the gap in the form of a chemical
Give four examples of a reflex action
Blinking coughing sneezing and withdrawing hand from hot objects
What are hormones?
Hormones are a type of chemical messenger which are released into the blood by certain glands
