General Science Questions (MCQs) for Competitive Examinations
General Science Multiple choice questions for GK paper in SSC, NDA, CDS, UPSC, UPPSC and State PSC Examinations. These questions are part of GKToday’s 35000+ MCQs Bank Course in GKToday Android App
1. Identify the noble gas utilized in radiotherapy?
[A] Neon
[B] Argon
[C] Radon
[D] Xenon
Show Answer
Correct Answer: C [Radon]
Notes:
Radon, a radioactive noble gas with atomic number 86, is used in radiotherapy. Created by disintegration of radium, its one of the heaviest gases and a health hazard. Radon gas, chemically inert yet radioactive, can accumulate in buildings and drinking water causing lung cancer. Furthermore, radon is noted for brilliant phosphorescence when cooled below its freezing point. Its most stable isotope, 222Rn, has a half-life of 3.8 days. Groundwater often has a higher 222Rn concentration than surface water due to less exposure to atmosphere.
2. Which of the following protein is found in nails?
[A] Keratin
[B] Histone
[C] Actin
[D] Elastin
Show Answer
Correct Answer: A [Keratin]
Notes:
Keratin is a family of fibrous structural proteins that is the key structural component of hair and nails. It is also the key structural material making up the outer layer of human skin. Besides, it provides the necessary strength and toughness for masticatory organs, such as the tongue.
3. In winter, at the time of hibernation, Toads maintain breathing through ____:
[A] Lungs
[B] Skin
[C] Both by Skin and Lungs
[D] Buccal cavity
Show Answer
Correct Answer: B [Skin]
Notes:
During hibernation in winter, toads or frogs spend the time tucked away deep in the soil, in the mud underwater or hidden amidst foliage or rotting plants. Outside of times of hibernation, they usually take in oxygen via the air, employing their lungs. However, during hibernation, they receive their necessary oxygen through their permeable skin. This is referred to as cutaneous gas exchange.
4. Intensive cultivation refers to ___:
[A] Raising production by intensive use of existing land
[B] Raising production by large scale use of imported inputs
[C] Production with intensive use of labour
[D] Production with intensive use of fertilizer
Show Answer
Correct Answer: A [Raising production by intensive use of existing land]
Notes:
Intensive farming is an agricultural intensification and mechanization system that aims to maximize yields from available land through various means, such as heavy use of pesticides and chemical fertilizers. It is characterized by a low fallow ratio, higher use of inputs such as capital and labour, and higher crop yields per unit land area.
5. BT seed is associated with ____:
[A] Rice
[B] Cotton
[C] Wheat
[D] Oil seeds
Show Answer
Correct Answer: B [Cotton]
Notes:
Cotton is the most popular of the BT crops. In BT cotton, BT gene was isolated and transferred from a bacterium Bacillus thurigiensis to American cotton. The American cotton was subsequently crossed with Indian cotton to introduce the gene into native varieties. The BT cotton variety contains a foreign gene obtained from Bacillus thuringiensis. This bacterial gene, introduced genetically into the cotton seeds, protects the plants from bollworm (A. lepidoptora), a major pest of cotton.
6. During photosynthesis, green plants use energy from sunlight to synthesize ___ from carbon dioxide and water:
[A] Fructose
[B] Glucose
[C] Sucrose
[D] Galactose
Show Answer
Correct Answer: B [Glucose]
Notes:
Photosynthesis is the process by which plants, some bacteria and some protistans use the energy from sunlight to produce glucose from carbon dioxide and water. This glucose can be converted into pyruvate which releases adenosine triphosphate (ATP) by cellular respiration. Oxy-gen is released through the stomata on the underside of the leaf; glucose is transported around the plant in the phloem vessels.
7. The cells of sclerenchyma tissue have their walls thickened due to which chemical substance?
[A] Cellulose
[B] Hemicellulose
[C] Lignin
[D] Pectin
Show Answer
Correct Answer: C [Lignin]
Notes:
Sclerenchyma cells are usually dead cells that have heavily thickened secondary walls containing lignin. The cells are rigid and non-stretchable and are usually found in non-growing regions of plant bodies, such as the bark or mature stems. Sclerenchyma is one of the three types of fundamental, tissue in plants; the other two types being Parenchyma and Collenchyma.
8. Which is the effect of antigen in an ill person?
[A] It increases the production of antibiotics
[B] It increases the production of W.B.C.
[C] It increases the production of anti-serum against bacteria
[D] It prevents the growth of bacteria
Show Answer
Correct Answer: A [It increases the production of antibiotics]
Notes:
Vaccines containing antigens are introduced into the body, stimulating the immune system response by instructing B cells, with assistance from T cells, to produce antibodies. Antibodies are produced to fight the weakened or dead viruses in the vaccine. The immune system prepares to destroy real and stronger viruses in the future. When new antigens enter the body, white blood cells called macrophages engulf them; process the information contained in the antigens, and send it to the T cells to mobilise immune system. Hence, introduction of antigens in any form in body induces the production of antibodies to boost immunity.
9. In how many parts is the human brain divided?
[A] 2
[B] 3
[C] 4
[D] 5
Show Answer
Correct Answer: B [3]
Notes:
The human brain is divided into three parts : The brainstem which has the pons, the midbrain, and the medulla oblongata. The cerebellum which forms the hindbrain along with the brainstem and is located below the cerebrum. The cerebrum which is the largest section of the brain, is divided into two hemispheres (the left and the right) each of which has four lobes: the frontal, the temporal, the parietal, and the occipital.
10. Which of the following mammals lay eggs?
[A] Bat
[B] Whale
[C] Weasel
[D] Platypus
Show Answer
Correct Answer: D [Platypus]
Notes:
The platypus, also known as the duck-billed platypus, is a semiaquatic egg-laying mammal endemic to eastern Australia, including Tasmania. Together with the four species of echidna, it is one of the five extant species of monotremes, the only mammals that lay eggs instead of giving birth.
