Question 1
Which of the following does not vary predictably with the depth of the aquatic environment?
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Salinity
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Temperature
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Penetration by sunlight
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None of these
Explanation:
Salinity varies with depth due to factors such as evaporation and freshwater input, but not consistently.
Question 2
The ozone layer protects the Earth from ___ by the Sun:
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Ultraviolet rays
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Infrared rays
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Gamma rays
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None of these
Explanation:
The ozone layer absorbs harmful ultraviolet radiation from the Sun.
Question 3
The ozone layer is present in the atmosphere in which layer?
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Exosphere
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Mesosphere
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Stratosphere
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None of these
Explanation:
The ozone layer is located in the stratosphere of the atmosphere.
Question 4
One of the main functions of the Earth’s ozone layer is to:
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Prevent global warming
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Filter out ultraviolet rays
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Absorb pollution
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All of the above
Explanation:
The primary function of the ozone layer is to filter harmful ultraviolet rays.
Question 5
The Pakistani population receives the largest dose of ionizing radiation from:
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Natural sources
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Fallout from nuclear weapons testing
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Nuclear medicine
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Nuclear power plants
Explanation:
Natural sources like cosmic radiation and radon contribute the most to radiation exposure.
Question 6
Which are air pollutants?
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Aerosols
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Sewage
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DDT
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Fertilizers
Explanation:
Aerosols are airborne particles that contribute to air pollution.
Question 7
Which of the following does not cause soil erosion?
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Wind
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Overgrazing
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Sun
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Water
Explanation:
The sun does not directly cause soil erosion, unlike wind, water, and overgrazing.
Question 8
The gas associated with global warming is:
Explanation:
Carbon dioxide is the primary greenhouse gas responsible for global warming.
Question 9
In water pollution, industries are said to be the:
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Line sources
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Point sources
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Area sources
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None of these
Explanation:
Industries release pollutants from specific locations, making them point sources.
Question 10
Among the following, the only secondary pollutant is:
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Sulphur peroxide
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Sulphur dioxide (SOâ‚‚)
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Ozone
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None of these
Explanation:
Ozone is formed by chemical reactions in the atmosphere, making it a secondary pollutant.
Question 11
Which of the following groups of plants can be used as indicators of SOâ‚‚ pollution of the air?
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Epiphytic lichens
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Ferns
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Liverworts
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Hornworts
Explanation:
Lichens are highly sensitive to air pollution and serve as indicators of the presence of sulfur dioxide.
Question 12
Prevailing winds affect a region’s climate by:
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Creating desert areas
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Causing more precipitation on one side of a mountain
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Affecting how much precipitation it receives
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Controlling the amount of solar energy it receives
Explanation:
Prevailing winds influence the amount and distribution of rainfall in a region.
Question 13
The carbohydrate content in a potato (per 100g) is:
Explanation:
Potatoes contain approximately 20.13 grams of carbohydrates per 100 grams.
Question 14
Which refrigerant is commonly used in cold storage in our country?
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Ethylene
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Carbide
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Liquid ammonia
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Sodium benzoate
Explanation:
Liquid ammonia is widely used as a refrigerant due to its high cooling efficiency.
Question 15
Those at greatest risk for food-borne illness include:
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Infants and children
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Pregnant women
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Immunosuppressed individuals
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All of the above
Explanation:
Vulnerable groups with weaker immune systems are at higher risk of food-borne illness.
Question 16
One of the following is a water-soluble vitamin:
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Vitamin A
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Vitamin D
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Vitamin C
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None of these
Explanation:
Vitamin C is water-soluble and must be provided regularly through the diet.
Question 17
The mango variety having a strong flavor is:
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Sindhri
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Chaunsa
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Langra
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None of these
Explanation:
The Langra mango is known for its strong, distinctive flavor.
Question 18
Proteins are made up of:
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Polynucleotide
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Polypeptide
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Oxyacetylene
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None of these
Explanation:
Proteins consist of polypeptide chains formed by amino acids.
Question 19
The pineapple variety suitable for canning is:
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Queen
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Kew
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Mauritius
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None of these
Explanation:
Kew pineapple is preferred for canning due to its firm texture and taste.
Question 20
The richest source of Riboflavin is:
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Papaya
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Mango
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Bael
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None of these
Explanation:
Liver and yeast are the richest sources of riboflavin (Vitamin B2).