Sensitivity and Coordination (Nervous System) Flashcards
What is the nervous system?
A network of nerve cells and fibres that carry nerve impulses to different parts of the body
What are the 2 parts of the nervous sytem?
Central Nervous system (CNS)
Peripheral nervous system (PNS)
What does the CNS consists of?
The brain and spinal cord
What does the PNS consists of?
A network of nerves cells that extends from the PNS to all parts of the body
What protects the brain and spinal cord?
The skull protects the brain while the spinal cord is filled with verte brae which makes up the back bone
What type of cells does the PNS consists of and what are they?
It consists of sensory cells called the receptors and effectors.
What are receptors and what are their functions?
Receptors are found in sense organs. Their function is to gather information from their surroundings. It it normally a result from a change in the environment.
What is a stimulus?
A change in the environment.
What are effectors?
They are muscles or gland that brings about a response to a stimulus.
What are neurons/nerves?
The are the basic unit of the nervous system. They transfer information around the body in the form of electric impulses.
What is the function of the relay neuron and where is it located?
The relay neuron carries message between the sensory and motor neuron.
What is the function of the motor nueron?
Takes message from the brain and spinal cord to the effectors.
What is the function of the sensory neuron?
Takes information from the receptor (found in sense organs) to the brain and spinal cord
How does the nervous system work?
1.Receptors found in sense organs detect a change in the environment (stimulus)
2. The information that the receptor gathered in then taken to the brain and spinal cord through the sensory neuron.
3. In the CNS the brain interprets and process the information received by the receptor and then decides on a response.
4. That message is then sent to the effector (muscle or gland) through the motor neauron to bring about a response.
Why is irritability important for the survival of an organism?
It helps an organism to be alerted to its surroundings and protects them from dangerous situations. It allows a range of responses to stimuli.
