1. Which of the following statements are true and which are false:

a) Bacteria are parasites
True

b) Ruby is an Oxide of Aluminum
True

c) In the Australian continent, days are longer than nights in June.
False

d) Gypsum is hydrated calcium carbonate chemically.
False

e) Twenty-three moons revolve around Saturn
False

f) Pluto is the coldest planet
True – provided that if we consider it a planet.

g) Chromite ore contains chromium oxide.
True

h) Mica is a nonconductor of electricity.
True

i) Sun is the biggest star in the universe.
False

j) The earth completes one rotation about its axis in 365.25 days.
False


4. Fill in the blanks:

(i) The capacity to do work is called energy.

(ii) The energy possessed by a body due to its position is called potential energy.

(iii) Kitab al-Manazir is a publication by a famous Muslim scientist about optics.

(iv) Nucleus usually lies in the centre of an animal cell.

(v) Calcium and phosphorus are the essential elements of bones.

(vi) Proteins are formed by combination of amino acids.

(vii) Rainwater dissolves sulphur dioxide to form sulphuric acid.

(viii) The set of instructions given to a computer is called command.
(ix) Chemicals such as penicillin which act on bacteria are called antibiotics.

(x) Comet Shoemaker Levy 9 hit the planet Mars in July this year (collision took place in July 1994)


7. Give brief answers for any five of the following:

(i) Name the two proteins found in milk.

Ans. albumin, globulin and casein


(ii) What organ of human body controls the amount of water and salt in blood?
Ans. kidneys

(iii) Drugs are classified into five major groups. Define any two.

Antibiotics
Antiparasitic
Antiviral
Antiprotozoal
Hormonal

(iv) How do chromosomes in a male and female differ in a human body.

Male XY
Female XX

(v) Which two gases do you exhale more than you inhale?
Ans. Carbon dioxide and oxygen

(vi) Name any two glands which secretes hormones in human body
Ans. Thyroid and Pituitary , Pancreas


9. Differentiate between any five of the following pairs.

(i) Veins and arteries:

Veins: carry deoxygenated blood to heart from body parts
and arteries carry oxygenated blood from body parts to heart.
Veins are thin and less elastic than arteries.

(ii) PNP and NPN transistor:

PNP transistors is the one in which one N, type semiconductor is sandwiched in between two P type or accepter diodes while NPN transistor is the one in which two N type semiconductors are fitted on the both sides of p-type semiconductor to allow to pass current from them.

(iii) Electronic current and static electricity:

Electricity occurs in two forms: static electricity and electric current. Static electricity consists of electric charges that stay in one place. An electric current is a flow of electric charges between objects or locations:

(iv) Concave and convex lens:

A convex lens curves outward; it has a thick center and thinner edges. Light passing through a convex lens is bent inward, or made to converge;

Concave lens: A diverging, or concave, lens is curved inward, with a thin center and thicker edges. Light passing through a concave lens bends outward, or diverges

(v) Fats and oils:

Fats are soft and greasy at ordinary temperatures, whereas fixed oils—as distinct from essential oils and petroleum—are liquid.

(vi) Absorption and adsorption:

Adsorption : the adhesion of a thin layer of molecules of some substance to the surface of a solid or liquid.

Absorption: the ability of a substance to absorb light, noise, or energy, or the fact that it does so


13. Which part of a plant do they belong to?

(i) Ginger
(ii) Raddish
(iii) Potato
(iv) Cinnamon
(v) Peanut
(vi) Saffron
(vii) Almond
(viii) Chillies
(ix) Spinach
(x) Tomato

Answers:

(i) Ginger........................Underground Stem
(ii) Raddish.....................Edible Root
(iii) Potato..................... Under ground Stem (tuber)
(iv) Cinnamon.................Bark of stem
(v) Peanut.....................Underground Seed/Fruit
(vi) Saffron...................Stigma of Flower
(vii) Almond...................Fruit
(viii) Chillies....................Edible pod with seeds/Fruit
(ix) Spinach...................Leaves
(x) Tomato ...................Fruit


15. Fill in the blanks.

(i) In a heat engine, heat energy is changed into _________ (mechanical energy, magnetic energy, light energy)

(ii) Frequency of audible sound in Hertz (Hz) is _________ (20 – 20,000Hz, 20,000 – 30,000Hz, 30,000 – 4,000Hz)

(iii) Deficiency of vitamin B causes _________ (rickets, beriberi, night blindness)

(iv) Cheapest source of producing electricity is _________ (coal, natural gas, water)

(v) The smallest unit of measurement of wavelength is _________ (micrometer, angstrom, nanometer)

(vi) The chemical generally used in refrigerators is _________ (ethylene glycol,freon, methyl alcohol)

(vii) The unit of ‘TON’ to specify air conditioners is equal to _________ (10,000 BTU/hour, 12,000 BTU/hour, 16,000 BTU/hour)

(viii) Unit of electricity ‘KILOWATT HOUR’ is the unit of (force, work, power)

(ix) Period of famous Muslim scientists is _________ (3rd – 5th century, 6th – 7th century, 7th – 13th century A.D.)

(x) Heat radiation travels at a speed equal to _________ (half the speed of light, speed of light, speed of wind)

__________________
No matter how fast i run or how far i go it wont escape me, pain, misery, emptiness.