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. Which of the following celestial bodies contains abundant quantities of helium3 as a potential source of energy?
[A] Moon
[B] Earth
[C] Sun
[D] Mars
Show Answer
Correct Answer: A [Moon]
Notes:
The Moon has been bombarded with large quantities of Helium-3 by the solar wind. It is thought that this isotope could provide safer nuclear energy in a fusion reactor, since it is not radioactive and would not produce dangerous waste products.
2. Which among the following metals is the hardest metal?
[A] Platinum
[B] Gold
[C] Iron
[D] Tungsten
Show Answer
Correct Answer: D [Tungsten]
Notes:
Tungsten has the highest tensile strength of any natural metal, with an ultimate strength of 1510 megapascals. Tungsten has the highest melting point (3422 °C, 6192 °F), lowest vapor pressure (at temperatures above 1650 °C, 3000 °F).
3. ____ is the cell organelle, in which the biochemical processes of respiration and energy production occur:
[A] Ribosomes
[B] Mitochondria
[C] Nucleus
[D] Chloroplast
Show Answer
Correct Answer: B [Mitochondria]
Notes:
Mitochondria is an organelle found in large numbers in most cells, in which the biochemical processes of respiration and energy production occur. It is for this reason that mitochondria are often referred to as the powerhouses of the cell mitochondria also play a key role in the ageing process as well as in the onset of degenerative disease.
4. Root cap is derived from
____:
[A] Dermatogen
[B] Calyptrogen
[C] Protoderm
[D] Histogen
Show Answer
Correct Answer: B [Calyptrogen]
Notes:
Calyptrogen is a layer of rapidly dividing cells at the tip of a plant root, from which the root cap is formed. It occurs in grasses and many other plants. The root cap is formed by several layers of cells that envelop the root tip externally. This covering of cells, of which the outermost ones are dead, envelops and protects the growing tip of root.
5. When we touch leaves of “Touch me not plant”, they close, these movements are called ____:
[A] Seismonastic movements
[B] Photonastic movements
[C] Nyctinastic movements
[D] Chemonastic movements
Show Answer
Correct Answer: A [Seismonastic movements]
Notes:
These types of mechanism have been termed seismonastic movements. The movement occurs when specific regions of cells lose turgor pressure, which is the force that is applied onto the cell wall by water within the cell vacuoles and other cell contents.
6. Consider the following statements about how plants absorb nitrogen:
- Plants absorb nitrogen in the form of inorganic nitrates or nitrites.
- Plants take in nitrogen in the form of organic compounds.
- Nitrogen is directly taken up by the plants from the atmosphere.
Which of the above statements is / are correct?
[A] Only 1 and 2
[B] Only 1 and 3
[C] Only 2 and 3
[D] All of these
Show Answer
Correct Answer: A [Only 1 and 2]
Notes:
Plants obtain nitrogen through their roots. In the soil, nitrifying bacteria change ammonia into nitrite (NO2 –) and then into nitrate (NO3 –), this process is known as nitrification. Furthermore, plants also absorb nitrogen in an organic form. Several organic compounds (compounds containing carbon) constitute the organic fraction of nitrogen in the soil. The organic matter in the soil exists as decomposing plant and animal residues, relatively stable decomposition-resistant compounds, and humus. The abundance of various forms of nitrogen can be altered by plant roots through the change in pH and secretion of organic compounds or oxygen.
7. In the context of agriculture, the term barani refers to ____:
[A] Rain-fed farming
[B] Irrigated farming
[C] Mixed farming
[D] Dry farming
Show Answer
Correct Answer: A [Rain-fed farming]
Notes:
Barani area are traditionally rain-fed areas. These are any low rain area where the rain-fed dry farming is practiced. Bagar tract, the dry sandy tract of land on the border of Rajasthan state adjoining the states of Haryana and Punjab, is an example of Barani land.
8. Which of the following bacterium causes crown gall disease in plants?
[A] Agrobacterium tumefaciens
[B] Pseudomonas fluorescens
[C] Bacillus thurigiensis
[D] None of the above
Show Answer
Correct Answer: A [Agrobacterium tumefaciens]
Notes:
Crown gall is a disease caused by the bacterium Agrobacterium tumefaciens (synonym Rhizobium radiobacter), which enters the plant through wounds in roots or stems and stimulates the plant tissues to grow in a disorganized way, producing swollen galls. As the disease progresses, plants lose vigour and may eventually die. In science of Biotechnology, it is considered as natural engineer.
9. Fat present below the skin surface in our body acts as a barrier against ____:
[A] Loss of heat from the body
[B] Loss of salt from the body
[C] Loss of essential body fluids
[D] Entry of harmful micro-organisms from the environment
Show Answer
Correct Answer: A [Loss of heat from the body]
Notes:
A layer of body fat acts as an insulator and traps heat. The subcutis is the deepest layer of skin. The subcutis, consisting of a network of collagen and fat cells, helps conserve the body’s heat and protects the body from injury by acting as a “shock absorber.
10. The strongest muscle (based on its weight) of the body is the masseter muscle and is located in the ___:
[A] Hand
[B] Jaw
[C] Thigh
[D] Chest
Show Answer
Correct Answer: B [Jaw]
Notes:
The masseter is located in the jaw and is one of the muscles of mastication or chewing. ? The bite strength of an average man is between 117 to 265 pounds. ? This ability to exert a force on an external object is an example of absolute strength.
