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. Biofortification is a ____:
[A] Method of plant breeding for disease resistance
[B] Method of developing resistance to insect pests
[C] Method of breeding crops to increase their nutritional value
[D] Strategy to combat unwanted nutrients in plants
Show Answer
Correct Answer: C [Method of breeding crops to increase their nutritional value]
Notes:
Biofortification is the breeding crops to increase their nutritional value. This can be done either through conventional selective breeding or genetic engineering. Biofortification differs from ordinary fortification because it focuses on making plant foods more nutritious as the plants are growing, rather than having nutrients added to the foods when they are being processed.
2. ____ 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.
3. Which one of the following is commonly known as Pond Silk?
[A] Yeast
[B] Rhizopus
[C] Ulothrix
[D] Spirogyra
Show Answer
Correct Answer: D [Spirogyra]
Notes:
Pond silk is the common name of Spirogyra (algae) because it is very slimy in shape. It is also known as pond silk, water silk, pond scum or mermaid’s trees because of its bright green silky appearance. Its filaments shine like silk due to the presence of mucilage and spiral shaped chloroplast.
4. Symbiotic Bacteria responsible for the fixation of atmospheric nitrogen are present in ____:
[A] Peas
[B] Oats
[C] Corn
[D] Wheat
Show Answer
Correct Answer: A [Peas]
Notes:
Nitrogen-fixing bacteria are microorganisms capable of transforming atmospheric nitrogen into fixed nitrogen. Rhizobium is one such bacteria that is associated with leguminous plants (e.g., various members of the pea family). It invades the root hairs of host plants and convert free nitrogen to ammonia, which the host plant utilizes for its development.
5. If in any water Body, there is high BOD value then it is generally ____:
[A] Very clean
[B] Highly productive
[C] Very polluted
[D] Highly unproductive
Show Answer
Correct Answer: C [Very polluted]
Notes:
Biochemical Oxygen Demand or Biological Oxygen Demand, is a measurement of the amount of dissolved oxygen (DO) that is used by aerobic microorganisms when decomposing organic matter in water. It indicates the amount of putrescible organic matter present in water. Therefore, a low BOD is an indicator of good quality water, while a high BOD indicates polluted water.
6. Bacteriophage was discovered by ____:
[A] Paul Ehrlich
[B] Burrill and Smith
[C] Felix D’Herelle and Frederick Twort
[D] Kluyver and Niel
Show Answer
Correct Answer: C [Felix D’Herelle and Frederick Twort]
Notes:
Bacteriophage refers to any of a group of viruses that infect bacteria. Bacteriophages were discovered independently by Frederick W. Twort in Great Britain (1915) and Felix d’Herelle in France (1917). D’Herelle coined the term Bacteriophage, meaning “bacteria eater”.
7. Consider the following hormones:
- Estrogen
- Progesterone
- Testosterone
Which of the above is/are classified as female hormones?
[A] (i) and (iii)
[B] (i) and (ii)
[C] (ii) and (iii)
[D] Only (iii)
Show Answer
Correct Answer: B [(i) and (ii)]
Notes:
There are several hormones in females which are naturally produced and secreted by the glands of the endocrine system. Among them, estrogen, and progesterone are secreted for the influence on a woman’s reproductive health and are termed as female sex hormones. Estrogen and progesterone are made by the ovaries.
8. Activity of an enzyme can be modulated by change of
____:
[A] pH
[B] Light
[C] Humidity
[D] Rainfall
Show Answer
Correct Answer: A [pH]
Notes:
Changes in pH which can accompany metabolic process such as respiration (aerobic glycolysis for example) can alter the conformation of an enzyme and hence enzyme activity such as salivarya mylase is effective in neutral condition, pepsin in acidic condition l.5 (less than pH 7) and trypsin in basic condition (more than pH 7).
9. The process of photosynthesis involves conversion of ____:
[A] Chemical energy into radiant energy
[B] Solar energy into chemical energy
[C] Chemical energy into mechanical energy
[D] Mechanical energy into solar energy
Show Answer
Correct Answer: B [Solar energy into chemical energy]
Notes:
Photosynthesis is the process by which light energy is converted into chemical energy by organisms. Carbon dioxide and water are the raw materials of this process. The light energy comes from the Sun and its end products are oxygen and glucose.
10. Wings of birds are ____:
[A] Integumentary outgrowth
[B] New structure
[C] Modified hind limbs
[D] Modified fore limbs
Show Answer
Correct Answer: D [Modified fore limbs]
Notes:
The wings are modified forelimbs of birds which are the key to bird flight. Each wing is composed of three limb bones, the humerus, ulna and radius. Wings are much bigger than our arms, but being made mostly of feathers and hollow bones makes them very light. Their shape uses the wind to make flying easier.
