Question

Section A: Very Short Answer Questions 1. What are nerves? What are different types of nerves present in human body? _____________________________________________________________ _____________________________________________________________ 2. What will happen spinal cord is not made up of small bones instead made from one single long bone? _____________________________________________________________ ____________________________________________________________ 3. What are the functions of eye lashes? _____________________________________________________________ ____________________________________________________________ 4. Why it is recommended not to use earbuds to clean ears? _____________________________________________________________ _____________________________________________________________ 5. Why mucus and tiny hair are present in our nose? _____________________________________________________________ _____________________________________________________________ Section B: Correct the following statements and rewrite 1. Taste buds are present on gums _____________________________________________________________ 2. Eyes help to keep balance. _____________________________________________________________
3. The nerve carry the message from sense organ to brain are motor nerves.

_____________________________________________________________

4. To open the blocked nose we should blow hard.

_____________________________________________________________

5. Writing is an example of reflex action.

_____________________________________________________________

Section C: Diagram based questions

1. Draw a well labelled diagram of human eye.

2. Name the smallest unit of nervous system. Also, draw a neat diagram of it.

Section D :Application based questions

1. Match the following

a).Circular transparent area in front of eye (i) Nostrils

b).External openings of nose (ii) Medulla

c). Actions not controlled by the brain (iii) Cornea

d). Part of brain that controls involuntary actions (iv) Pupil

e). Opening in the Centre of iris (v) Reflex actions

Ans: a) __________, b) ______, c)________, d)___________, e)___________

Q2. People of have brown eyes, some have green, blue, grey and black eyes.

Which part of the eye gives it special colour? And why?

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________​

Answer 1

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Section A

1. Nerves are cord-like structures whose primary role is to provide a pathway to conduct electrical impulses throughout the body. It essentially relays information from one part of the body to another.

The main 2 types of nerves are sensory nerves and motor nerves.

• Sensory nerves also known as afferent nerves, carry impulses from sensory receptors towards the brain.
• Motor nerves also known as efferent nerves, carry impulses away from the brain to muscles and glands.

2.  If the spinal cord would have been made of a single bone, the body could not have shown the movement. Hence, it is the series of vertebrae that extend from the cranium to the coccyx. These bones makes the spine present in it flexible.

3. Function of eyelashes:

• Defence our eyes.
• keeps away airborne dirt, dust, lint and other debris from reaching the delicate eye tissues.
• protect the eye from dust particles, foreign bodies, and perspiration.
• With eyes open, eyelashes catch some airborne debris.
• when eyes closed, eyelashes form a nearly impenetrable barrier against foreign irritants in the eye.

4.It is recommended not to use earbuds to clean ears becauseEar buds can lead to earwax blockage.Using an ear bud can block your ears. Earwax blockage can lead to dizziness, itching, loss of hearing and pain in the ears.

5. Mucus captures

• dust, germs, and other small particles that could irritate your lungs.

Deep in our noses, we have tiny hairs called cilia.

• These hairs constantly wave back and forth.
• Their job is to catch dangerous particles in mucus.
• Cilia then move the particle-filled mucus toward our throat

Section B

1. Taste buds are present on tongue.
2. Ears help to keep balance.
3. The nerve carry the message from sense organ to brain are sensory nerves.
4. To open the blocked nose we should blow lightly.
5. Writing is an example of voluntary actions.

Section C

1. refer attachement 1.
2. Neuron is the smallest unit of nervous system. refer attachment 2.

Section D

1. Match the column

a).Circular transparent area in front of eye

⟶ (iii) cornea

b).External openings of nose

⟶ (i) Nostrils

c). Actions not controlled by the brain

⟶ (v) Reflex actions

d). Part of brain that controls involuntary actions

⟶ (ii) Medulla

e). Opening in the Centre of iris

⟶ (iv) Pupil

2. People often have brown eyes, some have green, blue, grey and black eyes. Iris is responsible for it.

Eye color is determined by variations in a person's genes. Most of the genes associated with eye color are involved in the production, transport, or storage of a pigment called melanin. Eye color is directly related to the amount and quality of melanin in the front layers of the iris.

The main genes associated with eye colour include OCA2 and HERC2 and both are located in Chromosome 15.