#### SSLC Public Exam March 2019 Model Question

10th Standard

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Science

Time : 02:15:00 Hrs
Total Marks : 75
15 x 1 = 15
1. Hydra, a multi-cellular invertebrate of phylum cnidaria(coelenterata) can give rise to new offspring by various methods. Choose the method by which the offspring are produced with significant variations.

(a)

Budding

(b)

Regeneration

(c)

Sexual reproduction

(d)

Asexual reproduction

2. For minor surgeries in the body, doctors administer local anaesthesia to a part of the body so that the pain will not be felt by the patient. At which part, do you think, the nerve impulse is being arrested due to the effect of anaesthesia?

(a)

at cyton

(b)

at axon

(c)

at synapse

(d)

in the middle of axon

3. Thin walled non-motile spores are called_____

(a)

spirogyra

(b)

aplanospore

(c)

zoospore

(d)

akinete

4. Forelimbs of mammals have a common basic structure or pattern, but are different in their usage/ function in different animals. They can be called _______.

(a)

Homologous organs

(b)

Analogous organs

(c)

Vestigial organs

(d)

Rudimentary organs

5. The product obtained in the anaerobic respiration of yeast is .........................

(a)

Lactic acid

(b)

Pyruvic acid

(c)

Ethanol

(d)

Acetic acid

6. The particles in various forms are visible only under an ultramicroscope. A solution containing such particles is called __________.

(a)

true solution

(b)

colloidal solution

7. .......................... have equal number of neutrons.

(a)

Isobars

(b)

Isotones

(c)

Isotopes

(d)

Mass Numbers

8. Cancer cells thrive inside the body at a pH of _______

(a)

6.9

(b)

5.5

(c)

4.5

(d)

6

9. The third period contains elements. Out of these elements, How many elements are non-metals?

(a)

8

(b)

5

10. IUPAC name of Acetic acid is ________

(a)

Methanoic acid

(b)

Ethanoic acid

(c)

Ethanol

(d)

Di-ethyl ether

11. One astronomical unit is the mean distance between the centre of the Earth and centre of the ___________ .

(a)

Moon

(b)

Sun

(c)

Mars

12. Internal forces _______

(a)

are always balanced

(b)

are never balanced

(c)

mayor may not be balanced

(d)

none of these

13. The atomic number of natural radioactive element is _________.

(a)

greater than 82

(b)

less than 82

(c)

not defined

(d)

atleast 92

14. Fossil Fuel : Coal Biomass:_________

(a)

Cowdung

(b)

Petroleum

(c)

Uranium

15. An electric current through a metallic conductor produces _________ around it.

(a)

magnetic field

(b)

mechanical force

(c)

induced current

16. 20 x 2 = 40
17. Correct the mistakes, if any, in the following statements:
Primitive man evolved in America

18. Mention the significance of variation.

19. Say whether each of the following diseases is a metabolic disorder,a genetic disorder or a nutritional deficiency disease.
i)thalassemia ii)beriberi iii)diabetes mellitus iv)bubble boy syndrome v)scurvy vi)marasmus vii)obesity viii)Alzheimer's disease ix)nyctalopia x)haemophilia

20. To spot the error / mistake in the given statements
Correctthe mistakes, if any, in the following statements.
Fungi are green saprophytic or parasitic plants that subsist on live and decaying
organic matter or living organisms

What are the divisions of human nervous system?

22. Match the following with respect to dispersal of fruits / seeds:

 a) Autochory I) Lotus b) Anemochory II) Xanthiun c) Hydrochory III) Tridax d) Zoochory IV) Balsam
23. Draw the given diagram of paddy seed and label any two parts.

24. Name the three important blood proteins seen in plasma. Add a note on their functions.

25. Copy the diagram and label the following parts.(Bowman's Capsule, Loop of henle, Glomerulus, Proximal convoluted tubule, Distal convoluted tubule, Collecting duct)

26. What are ammoniatelic and ureotelic animals? Give examples.

27. Observe the following food web:

(i) Find out the wrong statement:

a) ‘A’ is a producer         b) ‘F’ is a herbivore

c) ‘H’ is an omnivore       d) ‘I’ is a climax carnivore

(ii) Find out how many food chains are present in the above food web.

28. Name the plants which are used in the production of bio-plastic

29. Water supply, sanitation and health are closely interrelated.
How does the contaminated water cause communicable diseases?

30. In the above case, Sekar observed that the water turned sweeter after sometime. Explain the reason for the same.

31. What is a true solution?

32. Calculate the number of molecules in 11 g of CO2

33. The pH values of certain familiar substances are given below:

 Substance pH value Blood 7.4 Baking soda 8.2 Vineger 2.5 Household ammonia 12

Analyse the data in the table and answer the following questions:
i) Which substances are acidic in nature?
ii) Which substances are basic in nature?

34. The hydroxide ion concentration of a solution is $1.0X10^{ -8 }m$What is the pH of the solution?

35. Match the following:

 Source pH - value 1. Acidic solution a. pH =7 2. Neutral solution b. pH > 7 3. Basic solution c. pH < 7
36. What is aluminothermic process?

37. Write the uses of aluminium.

38. C2H6O is the molecular formula for two compounds A and B. They have different structural formula.
i) What is this phenomenon known as?
ii) Give the structural formula of A and B.
iii) Write down their common and IUPAC names.
iv) Mention the functional groups of A and B.

39. To spot the error / mistake in the given statements
Allotropy is defined as the property by which an element can exist in more than one form that are chemically different but physically similar.

40. Give the four uses of Ethanoic acid

41. Least count of a screw gauge is an important concept related to screw gauge. What do you mean by the term least count of a screw gauge?

42. Write two principles that are used in rocket propulsion.

43. To find the odd one out
Momentum, Force, Acceleration, Newton

44. What is balanced force and unbalanced force?

45. Two bulbs of 70 W and 50 W are connected in parallel to an external potential difference. Which bulb will glow brighter? Why?

46. Draw Lead - acid accumulator cell and label the parts.

47. Light travels at 1.90 x 108 m/s in a crystal, what is the crystal’s index of refraction?

48. State Fleming's left hand rule.

49. 4 x 5 = 20
50. State whether true or false.Correct the statements that are false.
i)Variations give the organisms an individuality of their own.
ii)Charles Darwin postulated the use and disuse theory.
iii)To understand evolution, a branching diagram or a tree diagram is used to show the inferred evolution and the relationship among various biological species.
iv)Genetic engineering is the modification of the genetic information of living organisms by manipulation of DNA by adding,removing or repairing part of the DNA and changing the phenotype.

51. Mango and Coconut are both drupes.The mesocarp of mango is edible, while it is not so in coconut. Based on this fact, answer the following:
i) Which part of the coconut is edible?
ii) Why does the coconut have a fibrous mesocarp?
iii) Can you mention any other use of the fibrous mesocarp?

52. What is adaptation? Mention the adaptations found in the following mammals.
a) Whale b) Polar bear c) Kangaroo d) Herbivorous mammals.

53. Observe the picture given below and find out what type of energy is produced
i) Identify whether this energy is conventional or nonconventional.
ii) Draw the given diagram and label it with the parts given below:(battery, battery charger controller, solar incidence, DC load, battery system)
iii) In the given picture, _______energy is transformed into ______energy.

54. Give any 3 features of modern atomic theory.

55. Homologous series predict the properties of the members of the series. Justify this statement through its characteristics.

56. Explain Newton's second law of motion w!th an example.

57. The effective resistance of three resistors connected in parallel is 60/47 ?. When one wire breaks, the effective resistance becomes 15/8 ohms. Find the resistance of the wire that is broken.