50SCIENCE FORM 2 CHAPTER 1 REVISION

CHAPTER 1: THE WORLD THROUGH OUR SENSE1.1 Sensory Organs and Their Functions1.2 The Sense of Touch1.3 The Sense of Smell1.4 The Sense of Taste1.5 The Sense of Hearing1.6 The Sense of Sight1.7 Light and Sight1.8 Sound and Hearing1.9 Stimuli and Response in Plants

Part A: Multiple Choice Questions [20 marks]

Instruction: Circle the BEST answer.

1. Which of these pairs is matched correctly?A. Tongue – Chemicals in airB. Eyes – LightC. Ears – PressureD. Skin – Chemicals in food

2. __________ are special structures found in sensory organs to detect stimuli.A. SensesB. Nerve impulsesC. ReceptorsD. Olfactory cells

3. The following shows the pathway from stimulus to response.Stimulus → X → Sensory Nerves → Y → Motor Nerves → ResponseWhat is X and Y?

X YA. Brain EyesB. Lungs NoseC. Eyes LungsD. Nose Brain

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4. __________ in the skin enable us to determine how rough a surface is.A. Pressure receptorsB. Touch receptorsC. Sweat glandsD. Erected muscles

5. Most receptors in the skin lie in the A. dermisB. epidermisC. sebaceous glandD. fatty layer

6. Which of these areas of the skin has the most number of receptors?A. FingertipsB. CheekC. Back of the handD. Elbow

Questions 7 and 8 refer to the diagram below.

7. The part labeled R is known asA. smell receptorB. nostrilsC. mucus layerD. nasal cavity

8. Which of the following is the main function of the structure labeled P?A. Detects the chemical substance in foodB. Interpret the smell of foodC. Filters the air that flows into nostrilD. Detects the chemical substance in air

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9. The diagram shows the areas of the tongue which are sensitive towards a certain taste.

A student tastes soap solution with his tongue. Among the areas labelled K, L, M and N, which will be stimulated?A. KB. LC. MD. N

10. Which of the following senses is affected when a person is having flu?A. Sense of tasteB. Sense of touchC. Sense of hearingD. Sense of sight

11. Which of the following parts in the ear are responsible for balancing mechanism?I. CochleaII. OssiclesIII. Eustachian tubeIV. Semicircular canal

A. I and IIB. I and IVC. II and IIID. III and IV

Questions 12 and 13 refer to the pathway in ear below.Ear pinna → X → Ear drum → Y → Oval window → Z →Auditory nerve → Brain

12. Which of the following is represented by X, Y and Z?

X Y ZA. Eustachian

tubeSemicircula

r canalCochlea

B. Cochlea Semicircular canal

Auditory canal

C. Auditory canal

Ossicles Cochlea

D. Semicircular canal

Ossicles Eustachian tube

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13. What are the functions of Y and Z?

Y ZA. Vibrates when sound waves hit it Change vibration into impulsesB. Amplify sound waves Change vibration into impulsesC. Directs sound waves to the middle part

of the earHelps in maintaining body balance

D. Amplify sound waves Balances air pressure on both sides of the eardrum

14. The sense of sight enables us to gather all the information exceptA. shape of the objectsB. colour of objectsC. position of objectsD. temperature of objects

15. Which of these is the characteristic of the inner most layer of the eyeball?A. Contains black pigmentB. Made of strong musclesC. Has millions of photoreceptorsD. Has millions of blood capillaries

16. The diagram below shows a type of vision defect.

Which of the following is true about this vision defect?A. It could be due to the eye lens being too thinB. It is caused by an uneven curvature of the eyeballC. It can be rectified by wearing glasses with concave lensD. It could be due to eyeball too short

17. The inside walls of an auditorium hall or theatre are often hung with thick and pleated curtains. What are the properties of the curtain and the reason of using it?

Properties of the curtain ReasonA. Soft and porous To produce echoB. Hard and smooth Reflects soundC. Soft and porous Absorbs soundD. Hard and smooth Absorbs sound

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18. Which of the following response helps morning glory plants to obtain support as well as to climb higher for sunlight?A. Nastic movementB. ThigmotropismC. PhototropismD. Geotropism

19. Shoots of plants grow towards light.Which of these should be made the manipulated variable in an experiment to test the hypothesis above?A. The size of the boxB. Direction of the shoot growingC. The presence or absence of lightD. The presence or absence of water

20. What is the importance of hydrotropism to plants?I. To obtain sunlightII. To obtain waterIII. To obtain mineralIV. To obtain support

A. I and IIB. I and IVC. II and IIID. III and IV

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Part B: Subjective Questions [30 marks]

Instruction: Answer ALL questions.

1. The diagram shows the structures of the human skin.

a. On the diagram, label the structures P, R and S using the following words. [3 marks]

Pressure receptor Touch receptor Pain receptor

b. State one function of the skin. [1 mark]

___________________________________________________________________________

c. What are the two factors that influence the sensitivity of the skin? Briefly explain. [4 marks]

i. _____________________________________________________________________

_____________________________________________________________________

ii. ____________________________________________________________________

_____________________________________________________________________

d. Simon is having a blocked nose. He is unable to taste the flavor of his food. Explain why. [2 marks]

___________________________________________________________________________

___________________________________________________________________________

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2. The diagram below shows the cross section of an eyeball.

a. Name the labeled part. [6 marks]

B: ____________________________

C: ____________________________

D: ____________________________

E: ____________________________

F: ____________________________

G: ____________________________

b. What happened to part A and H when a person is reading a book? [2 marks]

___________________________________________________________________________

___________________________________________________________________________

c. State the one characteristic and one function of part F. [2 marks]

___________________________________________________________________________

___________________________________________________________________________

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3. The diagram below shows a light phenomenon.

a. Name the phenomenon and state two of the characteristics of the plane mirror for the phenomenon to occur. [3 marks]

___________________________________________________________________________

___________________________________________________________________________

b. What are the angle of incidence and the angle of reflection? [2 marks]

i. Angle of incidence: ______________________

ii. Angle of reflection: ______________________

c. Why the refraction can occur? Give one common example in daily life. [2 marks]

___________________________________________________________________________

___________________________________________________________________________

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d. Complete the drawing below. [3 marks]i.

ii.

iii.

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Part C: Bonus Question [5 marks]

There are two types of vision, namely stereoscopic vision and monocular vision. Complete the table below.

Stereoscopic Vision Monocular Vision(i) Sketch and label the region of vision:

[2 marks]

(ii) Give one example:[1 mark]

(iii) Give one importance:[2 marks]

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