Q: Which of the following pairs is incorrect ?

(A) Roentgen : X-ray

(B) Newton : Law of gravitation

(C) Faraday : Diffusion of gases

(D) Pasteur : Bacteriology



A: Roentgen : X-ray

B: Newton : Law of gravitation

C: Faraday : Diffusion of gases

D: Pasteur : Bacteriology



Correct Option: C  [ Faraday : Diffusion of gases ]

Remark:

Explanation: The incorrect pair is Faraday : Diffusion of gases. The diffusion of gases was studied and explained by Thomas Graham, not by Michael Faraday. Graham’s Law states that the rate of diffusion of a gas is inversely proportional to the square root of its density or molar mass. On the other hand, Michael Faraday is famous for his work on electromagnetism and electrolysis. The other pairs are correctly matched with their discoveries.


Q: The HIV virus affects the:

A: Leucocytes

B: Lymphocytes

C: Erythrocytes

D: None of these



Correct Option: B  [ Lymphocytes ]

Remark:

Explanation: The HIV (Human Immunodeficiency Virus) primarily attacks the lymphocytes, especially the CD4⁺ T-helper cells of the immune system. This weakens the body’s defense mechanism, making it vulnerable to various infections and diseases, eventually leading to AIDS (Acquired Immunodeficiency Syndrome).


Q: Which layer of gas in the atmosphere protects us from harmful ultra violet rays of the sun?

A: Oxygen

B: Carbon dioxide

C: Nitrogen

D: Ozone



Correct Option: D  [ Ozone ]

Remark:

The Ozone layer in the Earth’s stratosphere protects living organisms from the Sun’s harmful ultraviolet (UV) rays. Ozone (O₃) absorbs most of the high-energy UV radiation, preventing it from reaching the Earth’s surface, where it could cause skin cancer, cataracts, and damage to plants and marine ecosystems. This protective layer is mainly found between 10 to 50 km above the Earth’s surface.

Other options (for context)

  • Oxygen: Essential for respiration but does not block UV rays.
  • Carbon dioxide: A greenhouse gas responsible for trapping heat, not UV protection.
  • Nitrogen: Makes up most of the atmosphere but plays no role in UV absorption.


Q: In a society the growth and development that meets the current human needs and also conserves natural resources for future generations is known as:

A: Green economy

B: Holistic development

C: Sustainable development

D: Subsistence agriculture



Correct Option: C  [ Sustainable development ]

Remark:

Sustainable Development refers to growth that meets the needs of the present without compromising the ability of future generations to meet their own needs. It aims to balance economic progress, social equity, and environmental protection by conserving natural resources and reducing pollution for long-term ecological stability.

  • Green economy: Focuses mainly on eco-friendly industries.
  • Holistic development: Emphasizes overall human and social growth.
  • Subsistence agriculture: Involves farming mainly for self-consumption.


Q: Sugarcane is a type of

A: creeper

B: shrub

C: grass

D: tree



Correct Option: C  [ grass ]

Remark:

Explanation: Sugarcane (Saccharum officinarum) is a tall, jointed, perennial grass belonging to the family Poaceae. It has thick stems rich in sucrose, which is extracted to produce sugar. The plant reproduces mainly through stem cuttings (vegetative propagation). Its structure and growth habit are similar to other grasses like maize and bamboo.


Q: Sound-waves from a loud speaker is caused by:

A: frequency

B: vibrations

C: pitch

D: amplitude



Correct Option: B  [ vibrations ]

Remark:

Sound waves from a loudspeaker are produced by vibrations of its diaphragm. When an electric current passes through the speaker coil, it causes the diaphragm to move back and forth, creating compressions and rarefactions in the air. These pressure variations travel as sound waves to our ears.

  • Frequency: Determines pitch but does not create sound.
  • Pitch: A property of sound, not its cause.
  • Amplitude: Determines loudness but not the origin of sound.


Q: The red planet is

A: Venus

B: Saturn

C: Mars

D: Neptune



Correct Option: C  [ Mars ]

Remark:

Explanation: Mars is known as the Red Planet because its surface contains a large amount of iron oxide (rust), which gives it a reddish appearance. It is the fourth planet from the Sun and has two moons — Phobos and Deimos.


Q: The weight of a person on the surface of the moon will be about one-sixth of his weight on the surface of the earth. This is because

A: The moon has no air.

B: The moon has no water.

C: The gravity of the moon is about half of the earth.

D: The gravity of the moon is abouut one-sixth of that of the earth.



Correct Option: D  [ The gravity of the moon is abouut one-sixth of that of the earth. ]

Remark:

Explanation: The weight of a person depends on the gravitational force exerted by a celestial body. The Moon’s gravity is only about 1/6th that of the Earth’s because it has much less mass and a smaller radius. Therefore, an object or person weighing 60 kg on Earth would weigh only about 10 kg on the Moon. Although mass remains constant everywhere, weight changes according to the local gravitational acceleration (g). Hence, lower gravity results in lower weight on the Moon.


Q: Muscle fatigue is due to accumulation of

A: Carbon Dioxide

B: Creatinine

C: Lactic acid

D: Ethyl alcohol



Correct Option: C  [ Lactic acid ]

Remark:

Explanation: During vigorous physical activity, the oxygen supply to muscle tissues becomes insufficient. As a result, muscles switch from aerobic to anaerobic respiration. In this process, glucose is partially broken down into lactic acid. The accumulation of lactic acid lowers the pH of muscles, leading to pain, cramps, and temporary fatigue. Once sufficient oxygen is restored, lactic acid is converted back into carbon dioxide


Q: Entomology is the science that studies:

A: The origin and history of technical and scientific terms.

B: Insects

C: The formation of Rocks

D: Behavoiur of human beings



Correct Option: B  [ Insects ]

Remark:

Explanation: Entomology is a branch of Zoology that focuses on the study of insects, including their structure, classification, behavior, ecology, and evolution. Insects make up more than 75% of all known animal species on Earth and play crucial roles in pollination, decomposition, and food chains. Scientists who study insects are known as entomologists.

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