5 sense Organs and Their Functions for Class 3 Science

In this concept, 5 sense organs and their functions are discussed in detail. Here the students will get an idea about function of each sense organ.

After reading the concept students will be able to:

Identify 5 senses like touch, hearing, sight, smell and taste.
State the function of ear.
Explain the structure of tongue
Demonstrate how can we take care of our sense organs.

Each concept is explained to class 3 students using descriptions, illustrations, and concept maps. After you go through a concept, assess your learning by solving the two printable worksheets given at the end of the page.
Download the worksheets and check your answers with the worksheet solutions for the concept 5 Sense Organs and Their Functions provided in PDF format.

There are various kinds of changes happening in our surroundings.
We observe, feel or sense the differences in the surrounding by particular organs called the sense organs.
These organs collect information about the changes and passes to the brain. The brain works on these pieces of information and orders the body to act accordingly.

Our Sense Organs:

We have five different senses—vision, hearing, smell, taste and touch, and the sense organs related to these are the eyes, ears, nose, tongue and skin.

1. Eyes:

The eyes are the sense organs for vision. The pair of eyes notice the changes in the light in the surrounding.
The different parts of the human eye are shown in the following image—

The sensory cells in the eyes are called photoreceptors.
There are two types of photoreceptors—rod cells and cone cells.

Photoreceptors
Rod cells	Cone cells
Responsible for the vision in low light.	Responsible for colour vision in bright light.
There are about 120 million rod cells in the eye.	There are about 6-7 million cone cells in the eye.

2. Ear:

Humans can hear different sounds because of a pair of ears.
Hearing is possible due to the sound passing through the ear that is divided into the external ear, middle ear and inner ear.

The external ear helps collect different sounds and pass them to the middle part of the ear.
The middle ear contains a delicate part called the eardrum that vibrates after receiving the sound.
These vibrations are picked up by the inner ear that sends the stimulus to the brain.

3. Nose:

Humans can smell by their noses.

The air that enters the nose brings different odours that touch the smell receptors.
Our brain helps to understand and identify different smells after receiving the stimulus from the smell receptors in the nose.

4. Tongue

We get to know about the tastes of food by our tongue.
The tongue understands and identifies different tastes due to tiny receptors all over the tongue.

The back of the tongue is more sensitive to the bitter taste to avoid swallowing rotten/spoiled food.
The basic tastes that our tongue understands are sweet, sour, salty, bitter and savoury. The savoury taste is also called ‘umami’.

5. Skin:

The skin is the largest sense organ that covers all the other organs and protects us from external injuries.
It consists of different layers of tissues that help sense many stimuli.

Our skin can detect pain, itchiness, touch, vibration, heat, cold, pressure, etc.

Diseases Related to Sense Organs:

Sense organ	Diseases
Eyes	Farsightedness, Near-sightedness, Conjunctivitis
Ears	Ear squeeze, inflammation of inner parts, deafness
Nose	Sinusitis
Tongue	Swelling and infections
Skin	Acne, Psoriasis

How Can We Take Care of Our Sense Organs?

One should care about their sense organs to avoid any related diseases and ensure the proper functioning of the body.

Sense organ	How to take care
Eyes	Eat a healthy diet with green vegetables, fruits, milk, etc. Avoid watching mobile/TV/computer for a long time.
Ears	Never use pointed things to clean the ears. Avoid listening to loud music.
Nose	Never poke the nose by any pointed things. Clean the nose regularly while taking a bath
Tongue	Clean the tongue using a tongue cleaner and wash your mouth properly after eating the meals.
Skin	Bath regularly using good soap and consult the doctor if there are any rashes on the skin.

New Words:

Stimulus: Any kind of change in the surrounding that causes a sudden change in the body after sensing.

Did You Know?

The inner ear is also responsible to convey the brain about the change in the posture or position of our body.
Taste (from the tongue) and smell (from the nose) receptors give the perception of food flavour.
There is no taste as ‘spicy’! The ‘spicy’ or ‘hot’ is a state of pain perceived by the taste buds to the brain.