Form 3 Chapter 1.1 Human Nervous System

Which parts stated below are the central nervous system?

• spinal nerves

• brain

• spinal cord

• cranial nerves

Answer explanation

Which parts stated below are the peripheral nervous system?

• spinal nerves

• brain

• spinal cord

• cranial nerves

Answer explanation

Voluntary actions are:

• conscious actions and conducted under one’s will

• actions that occur immediately without conscious control

• controlled by the brain

• controlled by the medulla oblongata or spinal cord

Answer explanation

Examples of voluntary actions: reading, writing, speaking, eating, drinking, walking, running and exercising

Which part controls involuntary actions such as heartbeat, breathing and peristalsis?

• Medulla oblongata

• Spinal cord

Answer explanation

There are TWO types of involuntary actions.

The spinal cord controls involuntary actions known as reflex actions.

Choose the correct examples of reflex action:

• Withdrawing hand when it accidentally touches a hot object

• Secretion of saliva

• Withdrawing foot when it accidentally steps on a sharp object

• Peristalsis

• Sneezing when dust enters the nose

Answer explanation

Reflex actions are immediate actions controlled by the spinal cord (not brain).

These actions protect a person from injury.

The ___________ detects stimuli from the surroundings and converts them to nervous impulses.

Answer explanation

Nervous impulses are electrical signals that can travel along the nerve cells (nerves/neurons).

Tags

NGSS.MS-LS1-8

What are the FOUR functions of the nervous system?

(hint: remember the pathway of nervous impulse)

Answer explanation

1. detects stimuli

2. sends information in the form of impulses

3. interprets impulses

4. produces appropriate responses

The image shows the pathway of a nervous impulse in an action. Give two examples of the action involved.

(hint: voluntary action or involuntary action)

• Writing

• Breathing

• Peristalsis

• Withdrawing foot when it accidentally steps on a sharp object

• Walking

Answer explanation

Voluntary actions involve the brain but involuntary actions involve the spinal cord.

Changes in the size of the pupil is an involuntary action.

When entering a darker room, the pupil becomes ___________ so that more light can enter the eyes.

The following are structures involved when touching a hot object.

Which of the following pathways is correct?

• N, M, L, J, K

• L, K, J, M, N

• L, M, J, K, N

• M, N, J, L, K

Answer explanation