Kerala SSLC Biology Chapter 2 Questions Windows of Knowledge

Kerala SSLC Biology Chapter 2 Questions Windows of Knowledge and Responses English Medium

Select the correct answer.

Question 1.
The transparent anterior part of sclera
a. Conjunctiva
b. Cornea
c. Iris
d. Pupil
Answer:
b. Cornea

Question 2.
The liquid which helps in maintaining the shape of eye
a. Aqueous humour
b. Cerebrospinal fluid
c. Tears
d. Vitreous humour
Answer:
d. Vitreous humour

Question 3.
The visual pigment in rod cells
a. Rhodopsin
b. Retinal
c. Photopsin
d. Iodopsin
Answer:
a. Rhodopsin

Question 4.
The part that connects middle ear and pharynx
a. Oval window
b. Eustachian tube
c. Round window
d. Tympanum
Answer:
b. Eustachian tube

Question 5.
Fill up the blanks by observing the relationship between the first pair.
a. Planaria : Eyespot :: House fly : ……………..
b. Cochlea : Hearing :: Vestibule : ……………
c. The outer layer made up of connective tissues : Sclera :: The inner layer which has photoreceptors : ………………….
Answer:
a. Ommatidia
b. Body balancing
c. Retina

Question 6.
Find out the odd one and note down the common features of others.
a. Sclera, Choroid, Optic nerve, Retina ‘
b. Pinna, Malleus, Incus, Eustachian tube
c. Vestible, Semicircular canals, Iris, Vestibular nerve
Answer:
a. Optic nerve
Others are layers of eye.
b. Pinna
Others are parts of middle ear.
c. Iris
Others are parts related to body balancing.

Question 7.
The ciliary muscles of a person do not contract.
a. How does this affect his vision?
b. Does this affect the action of photoreceptors of retina? Why?
Answer:
a. He cannot see near objects.
b. It does not affect the action of photoreceptors of retina. It is because when light ray reaches the retina, the photoreceptors are stimulated.

Question 8.
The diagram given below shows the structure of ear.
Kerala SSLC Biology Chapter 2 Questions Windows of Knowledge 1
a. Redraw the picture.
b. Label the parts A, B, C, D.
c. Write down the name and function of E and F.
Answer:
Kerala SSLC Biology Chapter 2 Questions Windows of Knowledge 2
b. A. Tympanum, B. Auditory nerve, C. Ear ossicles, D. Eustachian tube
c.

  • E-Semicircular canals. It helps in the maintenance of balancing of body.
  • F-Cochlea. Helps in hearing.

Question 9.
Observe the figure and answer the questions given below.
Kerala SSLC Biology Chapter 2 Questions Windows of Knowledge 3
a. Identify the part labelled as A, B, C, D.
b. Write the peculiarities of part mentioned as A, C.
c. Write the functions of part indicated as B, D.
Answer:
a. A-Cornea, B- Sclera, C-Pupil, D-Optic nerve
b.

  • A-Slightly projected transparent anterior part of the sclera.
  • C – The aperture seen at the centre of the iris. The size increases and decreases depending on the intensity of light.

c.

  • Sclera – Gives firmness to the eye
  • Optic nerve – Transmits impulses from photoreceptors to the visual centre in the brain.

Question 10.
Arrange the statements suitably in the table given below.
a. Ligaments stretch.
b. Focal length decreases.
c. Ciliary muscles relax.
d. Ligaments relax.
e. Ciliary muscles contract.
f. Curvature of lens decreases.
g. Focal length increases
h. Curvature of lens increases.

While viewing near objects While viewing distant objects
.

.

.

.

Answer:

While viewing near objects While viewing distant objects
Focal length decreases Focal length increases
Ligaments relax Ligaments stretch
Ciliary muscles contract Ciliary muscles relax
Curvature of lens increases Curvature of lens decreases

Question 11.
The flowchart related to the process of hearing is given below complete it.
Kerala SSLC Biology Chapter 2 Questions Windows of Knowledge 4
Answer:
a. Tympanum
b. Ear ossicles
c. Cochlea
d. Auditory nerve
e. Cerebrum

Question 12.
Make suitable word pairs by using the words given in the box.
Jacobson’s organ, Housefly, Eye spot, Snake, Shark, Planaria, Ommatidia, Lateral line
Answer:

  • Snake – Jacobson’s organ
  • Housefly – Ommatidia
  • Shark – Lateral line
  • Planafia – Eye spot

Question 13.
The stages related to maintain the equilibrium of the body are given below. Arrange them in correct order.
a. Generates impulses
b. Maintains the equilibrium of the body
c. Body movements create movement in the fluid inside the vestibule and semicircular canals.
d. The impulses are transmitted by the vestibular nerve.
e. Cerebellum enables muscular movements.
f. Creates movements of the sensory hair cells.
Answer:
c. Body movements create movement in the fluid inside the vestibule and semicircular canals.
f. Creates movements of the sensory hair cells.
a. Generates impulses
d. The impulses are transmitted by the vestibular nerve.
e. Cerebellum enables muscular movements.
b. Maintains the equilibrium of the body

Question 14.
Kerala SSLC Biology Chapter 2 Questions Windows of Knowledge 5
a. Construct two questions related to this figure and see whether you can give any explanation.
b. Give suitable explanation of the questions.
Answer:
a.

  • Two images from an object are formed in two eyes. But we see only one image of the object. Why?
  • Draw a flow chart of light rays from the object to the centre of vision in brain.

b

  • Two images of the same object formed in the two eyes reach the visual area of the brain. The brain combines the two images together to give a single vision.
  • Light from the object → Eyes → Sensory nerve → Brain → Centre of vision.

Question 15.
“Receptors are modified neurons”. Justify the statement with examples of receptors in different sense organ.
Answer:
Receptors are modified neurons. They are of different types. Rods and cones of eye, sound receptors in ear, taste receptors on the tongue, olfactory receptors in nose and receptors in skin are examples.

Question 16.
Glaucoma is a serious eye defect. Analyze the statement.
Answer:
If the reabsorption of aqueous humour does not occur, it causes an increase in the pressure inside the eyes. This causes damage to the retina and the photoreceptor cells and ultimately leads to blindness.

Question 17.
Arrange columns B and C according ro ¡he daa given in column A.

A B C
Pupil Seen around lens Plenty of photoreceptors are present
Ciliary muscle The part of retina where the optic nerve begins Size of aperture regulated depending on the intensity of light
Blind spot Part of choroid seen behind the cornea The contraction and relaxation of these alter curvature of lens
The aperture seen at the centre of the iris. Photoreceptors are absent

Answer:

A B C
Pupil The aperture seen at the centre of the iris. Size of aperture regulated depending on the intensity of light
Ciliary muscle Seen around lens The contraction and relaxation of these alter curvature of lens ,
Blind spot The part of retina where the optic nerve begins Photoreceptors are absent

Question 18.
Observe the figure and answer the questions given below.
Kerala SSLC Biology Chapter 2 Questions Windows of Knowledge 6
a. Identify the situation indicated by the figure.
b. Identify the parts indicated as A, B.
c. How do A and B act in the situation?
Answer:
a. While viewing nearby objects
b. A – Ciliary muscles, B – lens
c. The contraction of ciliary muscles and the relaxation of ligaments help to increase the curvature of lens.

Question 19.
Prepare a flowchart related to the sense of vision by selecting suitable words given in the box.

Cornea, Auditory nerve, Blind spot, Aqueous humour. Retina, Eustachian tube, Light, Impulse, Pupil, Choroid, Vitreous humour, Cerebrum, Cochlea, Optic nerve, Sense of vision, Lens
Answer:
Light → Cornea → Aqueous humour → Pupil → Lens → Vitreous humour → Retina → Impulse → Optic nerve → Cerebrum → Sense of vision

Question 20.
Observe the picture and answer the questions – given below.
Kerala SSLC Biology Chapter 2 Questions Windows of Knowledge 7
a. Identify the picture
b. Identify the parts indicated as A, B, C, D.
c. What are the functions of C, D?
Answer:
a. Internal ear.
b. A- Semicircular canals B – Cochlea C – Autidory nerve D – Vestibular nerve
c.

  • Auditory nerve – Transmits impulses related to hearing to cerebrum.
  • Vestibular nerve – Transmits impulses related to body balancing to cerebellum.

Question 21.
Prepare a flowchart related to the experience of taste.
Answer:
Kerala SSLC Biology Chapter 2 Questions Windows of Knowledge 8

Question 22.
Find out the peculiarities of column A and rearrange columns B and C.

A

Organs

B

Secretions

C

Functions

Eye Endolymph Excretion of waste and regulation of temperature
Nose Cerebrospinal fluid Protection, nutrition, removal of urea
Ear Aqueous fluid Helps in functioning of olfactory receptors
Skin Mucus Nutrients and oxygen to the tissues
Sweat Transmission of auditory impulses

Answer:

A

Organs

B

Secretions

C

Functions

Eye Aqueous fluid Nutrients and oxygen to the tissues
Nose Mucus Helps in functioning of olfactory receptors
Ear Endolymph Transmission of auditory impulses
Skin Sweat Excretion of waste and regulation of temperature

Question 23.
Binocular vision gives us three dimensional vision. Then why do we close one eye when we aim at an object?
Answer:
Here distance is not important. Location of the object and eye must come in a straight line.

Question 24.
Ear canal → Cochlea → Tympanum → Auditory nerve
a. Correct the mistake, if any, in the above flowchart.
b. Modify the flow chart by adding the terms ‘oval window’ and ‘ear ossicles’
Answer:
a. Ear canal → Tympanum → Cochlea → Auditory nerve
b. Ear canal → Tympanum → Ear ossicles → Oval window → Cochlea →Auditory nerve

Question 25.
The flow chart related to the experience of smell is given below. Complete the flowchart.
Kerala SSLC Biology Chapter 2 Questions Windows of Knowledge 9
Answer:
a.

  • A – Aromatic particles dissolve in the mucus inside the nostrils, stimulate olfactory receptors.
  • B – Generate impulses
  • C – Impulses reach cerebrum through olfactory nerve

Question 26.
The symptoms of two below. eye defects are given
Kerala SSLC Biology Chapter 2 Questions Windows of Knowledge 10
Identify the defects. Write how these defects can be rectified.
Answer:
A – Glaucoma. Laser surgery
B – Cataract. Replace the lens with an artificial one.

Question 27.
Observe the picture and answer the questions given below.
Kerala SSLC Biology Chapter 2 Questions Windows of Knowledge 11
a. Identify the photoreceptor.
b. Write the pigment and components of this pigment.
Answer:
a. Rod cell
b. Rhodopsin – opsin, retinal

Question 28.
The features of a fluid are given below.

  • Seen between retina and lens
  • Jelly like substance

a. Identify the fluid.
b. Write its function.
Answer:
a. Vitreous humour
b. Helps in maintaining the shape of the eye.

Question 29.
Given below are the two diseases of eyes.
i. Colour blindness
ii. Night blindness
a. Which of these is caused by malnutrition?
b. Deficiency of which nutrient causes this disease?
c. Write the main symptom of this disease.
Answer:
a. Night blindness
b. Vitamin A
c. Cannot see objects clearly in dim light.

Question 30.
Statements related to sense organs are given below:
Choose the correct ones.
a. Taste buds are the chemoreceptors seen in the papillae.
b. Receptors are uniformly distributed all over the skin.
c. Impulses from the olfactory receptors reach the cerebrum through the olfactory nerve.
d. We experience taste when impulses from the taste buds reach the cerebellum.
Answer:
a. Taste buds are the chemoreceptors seen in the papillae.
c. Impulses from the olfactory’ receptors reach the cerebrum through the olfactory nerve.

Question 31.
Light rays which reflect from the object are focussed on the retina and an image is formed,
a. Write the peculiarities of this image.
b. How do the. images formed in the two eyes combine? What is its advantage?
Answer:
a. Small, inverted, real.
b.

  • Three dimensional image of the object is formed due to the activity of the brain.
  • Binocular vision becomes possible.

Question 32.
Vision is enabled when the impulse from the retina reaches the cerebrum through the optic nerve.
a. Draw a flow chart showing the pathway of light from cornea to retina.
b. There is no vision at the point where the optic nerve starts. Why?
Answer:
a. Light → Cornea → Aqueous humour → Pupil → Lens Vitreous humour → Retina → Optic nerve
b. Rod cells and cone cells are absent in the part from where the optic nerve begins / Photoreceptors are absent.

Question 33.
Rhodopsin Kerala SSLC Biology Chapter 2 Questions Windows of Knowledge 12 Retinal + Opsin
a. How is this reaction related to vision?
b. How does the deficiency of vitamin A cause poor vision in dim light?
Answer:
a.

  • When light rays fall, rhodopsin dissociates into retinal and opsin.
  • Generates impulses.
  • When impulses reach the cerebrum, vision is experienced.

b

  • Amount of retinal decreases.
  • Causes a decrease in the level of rhodopsin.
  • Resynthesis of rhodopsin gets blocked.
  • Cannot see objects clearly in dim light / night blindness.

Question 34.
Observe the figure given below and answer the questions: .
Kerala SSLC Biology Chapter 2 Questions Windows of Knowledge 13
a. Which is the receptor seen in the figure?
b. In which sense organ is this receptor seen?
c. What is the function of this receptor?
Answer:
a. Olfactory receptor
b. Nose
c. Gets stimulated by aromatic particles and generates impulses.

Kerala SSLC Biology Chapter Wise Questions and Answers