Question

Subject -Biology
1.Write the function of spinal cord,
2. With the help of suitable diagram define the structure of a neuron.
3. What are the voluntary and involuntary actions.
4.Prepare well all the syllabus of annual exam,​

Answer 1

FUNCTIONS OF SPINAL CHORD:-

Forms a connecting link between the brain and the PNS.

Provides structural support and builds a body posture.

Facilitates flexible movements.

Myelin present in the white matter acts as an electrical insulation.

STRUCTURE OF NEURON:-

A neuron varies in shape and size depending upon their function and location. All neurons have three different parts – dendrites, cell body and axon.

Parts of Neuron

Following are the different parts of a neuron:

Dendrites

These are branch-like structures that receive messages from other neurons and allow the transmission of messages to the cell body.

Cell Body

Each neuron has a cell body with a nucleus, golgi body, endoplasmic reticulum, mitochondria and other components.

Axon

Axon is a tube-like structure that carries electrical impulse from the cell body to the axon terminals that passes the impulse to another neuron.

Synapse

It is the chemical junction between the terminal of one neuron and dendrites of another neuron.

DIAGRAM IS ATTACHED

VOLUNTARY ACTIONS:-

When an action is produced with the involvement of thoughts, they are called the voluntary action. It involves actions like walking, eating, jumping and running. These actions are produced consciously. Both spinal cord and brain are involved and these coordinate with PNS to generate necessary movements.

INVOLUNTARY ACTIONS:-

Actions which take place without consciousness or willingness of an individual are called the involuntary action. Digestion, heart beating, sneezing, etc are few examples of involuntary actions.

Both involuntary and voluntary actions are controlled by same parts of the brain. Hindbrain and midbrain control the involuntary actions like salivation, vomiting, etc. All the body’s voluntary actions are controlled by the motor cortex in the frontal lobe of the cerebrum.