Selina solutions for कन्साइस बायोलॉजी [इंग्रजी] इयत्ता १० आयसीएसई chapter 11 - Sense Organs [Latest edition]

State the functions of the following:

Eyelids

State the functions of the following:

Eyelashes

State the functions of the following:

Tears

State the functions of the following:

Iris

State the functions of the following:

Ciliary muscles

Write in proper sequence the names of all the parts of the human eye through which the light rays coming from an object pass before they form an image on the retina.

Name the following:

Place of best vision in the retina of the eye.

Name the following:

Place of no vision in the retina of the eye.

Name the following:

Kind of retinal cells sensitive to dim light.

Name the following:

The circular opening enclosed by iris.

Name the following:

The fibres which collectively hold the lens in position.

Name the following:

Capacity of the eye to focus at different distances.

The kind of lens required to correct Myopia

Name the following:

The layer of the wall of the eye-ball that corresponds to the black lining of the box of a camera

Give the reason for the following:

Medicines dropped in the eye flow down into the nose.

Give the reason for the following:

A person from bright sunlight outside enters a poorly lit room and feels blinded for a short while.

Categorise the following parts under (i) external, (ii) middle and (iii) internal ear.

Ear drum, hammer, pinna, cochlea, anvil, stirrup, eustachian tube, tympanum, oval window, semi-circular canals.

State the functions of the following:

Semi-circular canals

Give the main function of the following:
Cochlea

State the functions of the following:

Auditory nerve

Human ear is concerned with hearing only.

Pinna concentrates and directs sound waves towards tympanum.

Given below is a diagrammatic representation of a part of the human ear.

1. Name the parts numbered 1-6.
2. Which parts of the ear shown here are complete.

The layer in the eye where sensory cells (rods and cones) are located ______.

The vitamin required for the synthesis of rhodopsin is ______.

An aperture that controls the passage of light into the eye is ______.

Tears have an antiseptic property due to the presence of ______.

Which of the following is responsible for the adjustment of the size of pupil?

The median canal of cochlea is filled with ______.

The thin, transparent extension of sclerotic layer found in front of the lens is ______.

The part of the inner ear which is responsible for hearing is ______.

The spiral organ possessing sensory cells for hearing is ______.

Which of the following structures equalises the air pressure on either side of the tympanum?

When a person comes out of a cinema hall after a noon show, he expriences a dazzling effect for a short period oftime. It happens due to degeneration of (P) ........... and regeneration of (Q) ........... pigments. Which of the following options is correct for P and Q?

Assertion (A): Lacrimal gland is a kind of endocrine gland which secretes an enzyme called thrombokinase.

Reason (R): Lacrimal gland is located in the upper outer portion of the orbit of the eye. Tears act as a lubricant and also have antiseptic property.

1. A is True and R is False.
2. A is False and R is True.
3. Both A and R are True.
4. Both A and R are False.

Assertion (A): Choroid layer provides nourishment to the eye and also prevents light rays form reflecting and scattering inside the eye.

Reason (R): Choroid layer is the outermost layer of the eyeball which surrounds the sclerotic layer. This layer contains two types of pigments - Rhodopsin and Iodopsin.

1. A is True and R is False.
2. A is False and R is True.
3. Both A and R are True.
4. Both A and R are False.

Assertion (A): The image formed on the retina is straight and real. 

Reason (R): Images from the retina are transmitted to the brain through the optic nerve. Then brain interprets it in an upright position. Both the eyes form two images but the brain interprets them as one due to the overlapping of the images.

1. A is True and R is False.
2. A is False and R is True.
3. Both A and R are True.
4. Both A and R are False.

Assertion (A): Myopia is caused due to the shortening of the eyeball from front to back. 

Reason (R): Myopia can be corrected by using suitable convex (converging) lens and the power of the glasses used is mentioned in plus “+”.

1. A is True and R is False.
2. A is False and R is True.
3. Both A and R are True.
4. Both A and R are False.

Assertion (A): Semi-circular canals are present in the middle ear and they contain sensory cells responsible for the static balance of the body. 

Reason (R): One end of each of the three semicircular canals is widened to form an ampulla which contains the sensory cells for dynamic balance.

1. A is True and R is False.
2. A is False and R is True.
3. Both A and R are True.
4. Both A and R are False.

Assertion (A): The tube/canal which transmits the air currents from the pinna to tympanum is termed as eustachian tube.

Reason (R): The eustachian tube equalizes the air pressure on either side of the ear drum allowing it to vibrate freely.

1. A is True and R is False.
2. A is False and R is True.
3. Both A and R are True.
4. Both A and R are False.

Assertion (A): The human ear is responsible for hearing, dynamic equilibrium and also static balance.

Reason (R): Cochlea, semi-circular canals and vestibule (utriculus and sacculus) are responsible for hearing, dynamic balance and static balance respectively.

1. A is True and R is False.
2. A is False and R is True.
3. Both A and R are True.
4. Both A and R are False.

Name the following:

The photosensitive pigment present in the rods of the retina.

Name the following:

The part which equalises the air pressure in the middle and external ear.

Name the following:

The ear ossicle attached to the tympanum.

Name the following:

The tube which connects the cavity of the middle ear with the throat.

Name the following:

The part of the eye responsible for its shape.

Name the following:

The nerves which transmit impulse from ear to the brain.

Name the following:

The photoreceptors found in the retina of the eye.

Name the following:

The eye defect caused due to shortening of the eye ball from front to back.

Note the relationship between the first two words and suggest the suitable word/words for the fourth place.

Cones : Iodopsim :: Rods : ______.

Note the relationship between the first two words and suggest the suitable word/words for the fourth place.

Eyes: Photoreceptors :: Ears : ______.

Note the relationship between the first two words and suggest the suitable word/words for the fourth place.

Ears: Auditory nerve :: Eyes : ______.

Note the relationship between the first two words and suggest the suitable word/words for the fourth place.

Ear pinna : Auricle :: Inner ear : ______.

Note the relationship between the first two words and suggest the suitable word/words for the fourth place.

Semi-circular canal : Ampulla :: Cochlea : ______.

Match the terms in column I with those in column II and write down the matching pairs.

Given below is the structure of a human eye. Read the information below the diagram and fill in the blanks:

The wall of the eyeball is composed of three concentric layers. The middle layer of the eyeball is (a) ______ richly supplied with blood vessels whereas the innermost layer is (b) ______ which contains two types of sensory cells. (c) ______ is the extension of the middle layer of the eyeball which regulates the size of the (d) ______. The image formed on the yellow spot of the eye is the (e) ______.

State whether the following statements are true (T) or false (F). If false, correct them by changing any one single word in each.

Deafness is caused due to rupturing of the pinna.

State whether the following statements are true (T) or false (F). If false, correct them by changing any one single word in each.

Semi-circular canals are concerned with static (positional) balance.

Where is the following located?

Yellow spot

State the Location of: 
Lacrimal gland

Mention, where in living organism is the following located and state their main function:
Organ of corti

Where are the following located?

Eustachian canal

Mention the exact location of the following : 
 Incus 

Given below is a set of five parts. Rewrite them in correct sequence.
Cochlea, tympanum, auditory canal, ear ossicles, oval window.

Given below is a set of five parts. Rewrite them in correct sequence.

Conjunctiva, retina, cornea, optic nerve, lens.

Write the main functional activity of the following structure.

Cochlea

Write the main functional activity of the following structure.

Semicircular canal

State the functions of the following:

Iris

Write the main functional activity of the following structure.

Choroid

Write the main functional activity of the following structure.

Ciliary body and suspensory ligament

Complete the following table by filling in the blank spaces.

Name the following:

Two pigments of the sensory cells.

Name the following:

Two types of adaptations.

Name the following:

Two kinds of accomodations.

Name the following:

Three layers of the eye ball.

Name the eye defects caused due to each of the following:

Define the following term:

Conjunctiva

Define the following term:

Lysozyme

Define the following term:

Adaptation

Define the term.

Power of accommodation of the eye.

Define the following term:

Ear ossicles

Differentiate between members of the following pair with reference to what is asked in the bracket.

Myopia and Hyperopia (type of lens used for correction).

Differentiate between members of the following pair with reference to what is asked in the bracket.

Rods and cones (sensitivity).

Differentiate between members of the following pair with reference to what is asked in the bracket.

Aqueous humour and vitreous humour (location).

Differentiate between members of the following pair with reference to what is asked in the bracket.

Near and distant accomodation (shape of lens).

Differentiate between members of the following pair with reference to what is asked in the bracket.

Dark and light adaptation (pigments which will be regenerated).

Differentiate between members of the following pair with reference to what is asked in the bracket.

Night blindness and colour blindness (sensory cells which cannot function properly).

Give the reason for the following:

Medicines dropped in the eye flow down into the nose.

Give reason:

Three small bones of ear ossicles are advantageous as compared to one single bone for hearing.

Give reason:

Blind spot is considered as 'area of no vision'.

Mention the characteristics of the image that falls on the retina of the eye.

Describe the mechanism of focusing the image of a distant object in your eye when you raise your head after reading a book.

By closing the eyes and gently pressing them by your palms, you may see some specks of brilliant light. How do you get this sensation while there is no light entering your eyes?

Name the three ear ossicles.

How do the three ear ossicles contribute in the mechanism of hearing?

The figures (A) and (B) given below are showing some kind of adjustment. Study the figures and answer the questions that follow.

A

B

1. Identify the kinds of adjustments done in the figures (A) and (B).
2. Distinguish between the adjustments of figures (A) and (B) on the basis of:
   1. The size of pupil.
   2. The pigment which gets regenerated.
   3. Cells of the retina.

With reference to human eye answer the question that follow:

Name the part of the eye associated with the regulation of the size of pupil.

With reference to human eye answer the question that follow:

Name the part of the eye associated with the regulation of the shape of lens.

With reference to human eye answer the question that follow:

Name the part of the eye associated with keeping the lens moist and protecting it from physical shock.

With reference to human eye answer the question that follow:

Name the part of the eye associated with the layer providing nourishment to the eye.

With reference to human ear answer the question that follow:

Name the part of the ear associated with Static balance.

With reference to human ear answer the question that follow:

Name the part of the ear associated with dynamic balance.

With reference to human ear answer the question that follow:

Name the part of the ear associated with hearing.

With reference to human ear answer the question that follow:

Name the part of the ear associated with the amplification of vibrations.

The figure given below refers to the vertical section of the eye of a mammal. Study the figure carefully and answer the following questions.

1. Label the guidelines shown as 1 to 10.
2. Write one important role of parts shown as 3 and 7.
3. Write one structural difference between the parts shown as 9 and 10.
4. Mention one functional difference between the parts shown as 6 and 8.

Given alongside is a diagram depicting a defect of the human eye. Study the same and answer the questions that follow:

1. Name the defect shown in the diagram.
2. Give two possible reasons for this defect.
3. Name the parts labelled 1 to 4.
4. Name the type of lens used to correct this eye defect.
5. Draw a labelled diagram to show how the above mentioned defect is rectified using the lens named above.

1. Draw a neat and well labelled diagram of the membranous labyrinth found in the inner ear.
2. Based on the diagram drawn above in (i), give a suitable term for each of the following descriptions:
   1. The structure responsible for hearing.
   2. The sensory cells that help in hearing.
   3. The membrane-covered opening that connects the middle ear to inner ear.
   4. The nerves that carry impulses from the ear to the brain.
   5. The tube which equalises the air pressure on either side of the ear drum.

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

1. Give the collective biological term for Malleus, locus and Stapes.
2. Name the parts labelled A, B and C in the diagram.
3. State the functions of the parts labelled 'A' and 'B'.
4. Name the audio receptor region present in the part labelled 'A'.

Draw a labelled diagram of the inner ear.

Name the part of the inner ear that is responsible for static balance in human beings.

Have a look at the posture of this girl who is reading a book and answer the questions which follow:

1. Name the problem she is facing.
2. What are the two conditions shown in sections A and B of the eye as applicable to her.
3. What kind of reading glasses does she need?

A	B

The figure given below shows the principal parts of a human ear. Study the diagram and answer the following questions.

1. Label the parts 1 to 8.
2. State the role of parts 6, 7 and 8.
3. Why is it harmful to use a sharp object to remove ear wax? Mention the number and name of the part involved.

Given below is the internal structure of human ear. Match the structures marked (a) to (e) with their correct function.

The internal structure of human ear		Function
	1.	Responsible for hearing.
	2.	Concerned with balance and spatial orientation.
	3.	Transmits impulses from ear to brain.
	4.	Contains sensory cells for dynamic balance.
	5.	Concerned with static balance.