Eyes and Brain

Sense organ

by Elena Gonnawa

​Describe the functions of the sense organs of the human body.

S3LT-IIa-b-1

​1. Eye - It is the sense organ of sight (seeing). The eyes help you

recognize the things around you like the shape, size, and color.

​

​Cornea

• It serves as the transparent covering of the eye.

• It is where the light passes/enters through.

• Sclera White part of the eye.

Iris

• It is found behind the cornea.

• It controls the amount of light that enters the eye.​

Pupil

• It is found in the middle of the eye.

• It determines the amount of light that enters the eye.

​Lens

• It is found behind the iris.

• It focuses the light rays on the retina, and it also throws an upside-down picture.

​

Retina

• The line at the back of the eye.

• It contains two types of cells, the rods, and the cones.

• It changes the light into signals, the image will be formed.

• It has millions of tiny cells connected to the optic nerve.

​

Optic Nerve

• Responsible in sending images or information to the brain.

• Nerve endings that connect the eye to the brain

​2. Ear – It is a sense organ used for hearing. It is helps us determine if

the sound we hear is pleasant or unpleasant.

​Pinna/ Earlobe/Auricle-It is the outer part of the ear. Responsible in collecting sounds.

Ear Canal It is a tube where earwax is formed.

It is where the collected sounds travel through.

Eardrum It is found at the end of the ear. It is like a thin piece of skin stretched tight like a drum. It is where the ear canal directs the sounds

that makes it vibrates when reaches

​Hammer, Anvil, Stirrup Bones connected behind the eardrum. It is where the eardrum passes the vibration.

Cochlea-It is a snail-like part which is filled with liquid.

Detects the vibration

Auditory Nerves Responsible in sending messages to the brain.

​Nostrils-Two holes of the nose. It has hairs that keep dust out of the nose.

It is where the air enters through.

Nasal cavity- It is a space behind your nose.

Its walls are wet, warm, and covered with mucus, a sticky liquid that traps dusts, dirt or germs which enter the nostrils and were not filtered by the nose hairs.

It is where the air will pass through.

Olfactory nerve Responsible in carrying the message to the brain.

​

​4. Tongue - It is a sense organ used for tasting. It is responsible in

recognizing our favorite food like sweet, sour, bitter, and salty. Our

tongue is covered with a layer of bumps called papillae which contains the taste buds. The taste of the food passes through the bumps of the tongue, the taste buds, and the nerve endings. The nerve sends messages to the brain for the interpretation of the taste of the food.

​5. Skin - It is the sense organ of touch/feel. It is responsible in

recognizing if it is hard, soft, rough, smooth, hot, or cold. It is the

largest sense organ. It covers the entire body. The skin has two

layers. The epidermis, which is the outer layer of the skin. This is

where dead cells are found. This part produces melanin which gives the actual color of our skin.

The dermis is the inner layer which contains nerves, blood vessels, sweat and oil glands. The oil glands keep the hair and skin soft and moist.

Multiple Choice

PERFORMANCE TASK

Read and understand the following situations. Choose the correct answer.

1. Why do we need to apply sunblock on our faces, hands, and body

when we go out under the sun?

• To prevent us from sunburn.

• It reduces the signs of aging.

• It reduces the risk of skin cancer.

• All the above.

Multiple Choice

Read and understand the following situations. Choose the correct answer.

2. What will you do if a tiny particle enters your eye while playing outside

the house?

• Blink to allow your tears to wash it out.

• Rub your eye.

• Go to sleep.

• Ask your playmate to remove.

Multiple Choice

Read and understand the following situations. Choose the correct answer.

3. How do you protect your ears?

• Avoid noise activities when possible.

• Blowing the nose too hard will not destroy the ears.

• You can shout at anyone's ears.

• Clean your ears with sharp objects.

Multiple Choice

Read and understand the following situations. Choose the correct answer.

4. Which of the following is sensed by the nose?

• the sweet smell of flowers

• sweet taste of corn

• sweet music

• sweet romantic view

Multiple Choice

Read and understand the following situations. Choose the correct answer.

5. How will you maintain a healthy tongue?

• Avoid drinking and eating very hot drinks and foods respectively.

• Eat the right kinds of food regularly.

• Brush your tongue regularly to get rid of food particles.

• All the above.

Multiple Choice

POST ASSESSMENT

Read and understand the following then choose the correct answer.

1. It determines the amount of light that enters the eye.

• cornea

• iris

• pupil

• retina

Multiple Choice

Read and understand the following then choose the correct answer.

2. As we breathe in, what part of our nose where air passes through?

• nasal cavity

• nostrils

• cornea

• nerve

Multiple Choice

Read and understand the following then choose the correct answer.

3. This contains nerves, blood vessels, sweat and oil glands.

• epidermis

• hair follicle

• stirrup

• dermis

Multiple Choice

Read and understand the following then choose the correct answer.

4. What nerve is responsible in sending a message to the brain for

interpretation so that you will know if the sound is pleasant or unpleasant?

• auditory nerve

• olfactory nerve

• optic nerve

• sound waves

Multiple Choice

Read and understand the following then choose the correct answer.

5. It controls the amount of light that enters the eye.

• lens

• iris

• pupil

• retina