-->

The Nervous System

Question
ICSEENIBI10003427

Given below is the diagram of the human ear. Study the same and answer the questions which follow:



(i) Give the biological term for the part labelled ‘A’ and state its function.

(ii) Name the part labelled ‘B’ and state its function.

(iii)Name the part labelled ‘C’ and state its function.

(iv)Give the function of ear wax. 

Solution

(i) Ear ossicles (malleus, incus and stapes): Ear ossicles receive vibrations from the ear drum and magnify them. The vibrations of the stapes are transmitted to the membrane of the oval window.
(ii) Eustachian tube: The Eustachian tube equalises the air pressure on either side of the ear drum allowing it to vibrate freely.
(iii)Auditory nerve: The auditory nerve transmits nerve impulses from the cochlea in case of sound and from the semicircular canals in case of balancing to the brain.
(iv)Function of ear wax:
1) Ear wax has insect repellent properties and hence prevents the entry of insects into the auditory canal. It also prevents the entry of dust particles.
2) It lubricates and protects the ear.

Some More Questions From The Nervous System Chapter

(c) Given below are six sets with four terms each. In each set, a term is an odd one and cannot be grouped in the same category to which the other three belong. Identify the odd one in each set and name the category to which the remaining three belong. The first one has been done as an example:

Example: Fructose, Sucrose, Glucose, Calcium
Odd term: Calcium
Category: Carbohydrates

Semicircular canals, cochlea, tympanum, utriculus

Choose the correct answer from the four options given below:

The ventral root ganglion of the spinal cord contains cell bodies of the

Given below is an example of certain structures and their special functional activities.
For example : Eye and vision. 

On a similar pattern, complete the following:

Neurotransmitters ........................ 

Give the biological/technical terms for the following:

The fluid present between the layers of meninges

The change in an organism resulting due to stimulus

Given below are five groups of terms. In each group, arrange and rewrite the terms in the correct order so as to be in a logical sequence. For example,

Question: Implantation, Parturition, Ovulation, Gestation, Fertilisation.

Answer: Ovulation, Fertilisation. Implantation. Gestation, Parturition.

Draw a diagram of the human eye as seen in a vertical section and label the parts

which suit the following descriptions relating to the

i. Photosensitive layer of the eye.

ii Structure which is responsible for holding the eye lens in its position.

iii Structure which maintains the shape of the eye ball and the area of no vision.

iv Anterior chamber seen in front of the eye lens.

v Outer most transparent layer seen in front of the eye ball.

Differentiate between the following pairs on the basis of what is mentioned within brackets:

Cerebrum and Spinal cord (arrangement of nerve cells)

Give biological reasons for the following:

Throat infections can lead to ear infections.

Give biological reasons for the following:

The hand automatically shows the direction to turn a cycle without thinking.