Human Nervous System Overview

What are the two main components of the human nervous system?

Which of the following is an example of a voluntary action?

Which part of the eye helps to focus light directly onto the retina?

What is the role of rod cells in the retina?

Which function does the human nervous system NOT perform?

What characterizes involuntary actions?

Which component of the eye is primarily responsible for controlling the amount of light entering the eye?

What is the primary function of the aqueous humour in the eye?

Human Nervous System

The human nervous system is made up of the central nervous system and the peripheral nervous system
The central nervous system includes the brain and spinal cord
The peripheral nervous system includes cranial nerves (12 pairs) and spinal nerves (31 pairs)

Function of Human Nervous System

Controls and coordinates organs and body parts
Detects stimuli
Sends information in the form of impulses
Interprets impulses
Produces appropriate responses

Voluntary Actions

Conscious actions, such as writing, reading, singing, eating, and walking;
Conscious actions are controlled by the brain

Involuntary Actions

Occur immediately without conscious control or prior thoughts, such as heartbeat, breathing, peristalsis, secretion of saliva, and sneezing.
Can be classified into two:
- Actions involving the medulla oblongata, including heartbeat, breathing, and peristalsis
- Actions involving the spinal cord (reflex actions), such as sneezing when dust enters the nose

Structure of the Eye

The retina has two photoreceptors:
- Rod cells – sensitive to different light intensities
- Cone cells – sensitive to colours of light.

This quiz covers the basics of the human nervous system, including its structure and functions. It delves into both voluntary and involuntary actions and how the central and peripheral nervous systems work together to control the body's responses. Test your understanding of this vital system!