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 is correct about effective nuclear charge experienced by the orbital?
[A] it increases with increase of azimuthal quantum number
[B] it increases with increase of magnetic quantum number
[C] it decreases with increase of azimuthal quantum number
[D] It is same everywhere
Show Answer
Correct Answer: C [it decreases with increase of azimuthal quantum number]
Notes:
Because of the screening effect, the net positive charge experienced by the electron from the nucleus is lowered and is known as effective nuclear charge. Effective nuclear charge experienced by the orbital decreases with increase of azimuthal quantum number(l).
2. Who discovered electron?
[A] John Dalton
[B] James Chadwik
[C] Ernest Rutherford
[D] J J Thomson
Show Answer
Correct Answer: D [J J Thomson]
Notes:
Electron was discovered by an Irish scientist J J Thomson and electron is the first subatomic particle to be discovered. J J Thomson is notable for proposing the water melon model which is also called as plum pudding model.
3. Which of the following gases helps in bread/cake fermentation so as to make it soft and spongy?
[A] Carbon Monoxide
[B] Hydrogen
[C] Carbon Dioxide
[D] Oxygen
Show Answer
Correct Answer: C [Carbon Dioxide]
Notes:
Fermentation is an anaerobic chemical process that breaks down glucose molecules. In baking, yeast consumes sugar and converts it into carbon dioxide and alcohol, making the dough rise. This gas gets trapped in the strands of gluten, resulting in air pockets that cause the dough to rise and form the characteristic spongy texture of bread and cakes. Further, the creation of lactic and acetic acids during fermentation augments this dough handling process, improves flavor, enhances the texture, and extends the shelf-life of the baked products.
4. The biological process in which both aerobes and anaerobes degrade organic matter is ____:
[A] Digesting
[B] Composting
[C] Manuring
[D] Nutrifying
Show Answer
Correct Answer: B [Composting]
Notes:
Composting is the depomposition of plant remains and other once-living materials to make an earthy, dark, crumbly substance that is excellent for enriching soil. It is the chief way to recycle wastes.
5. The special modified epidermal cells surrounding stomatal pore are called ____:
[A] Accessory cells
[B] Epithelial cells
[C] Guard cells
[D] Subsidiary cells
Show Answer
Correct Answer: C [Guard cells]
Notes:
The pore is bordered by a pair of specialized parenchyma cells known as guard cells that are responsible for regulating the size of the opening. Guard cells are specialized cells in the epidermis of leaves, stems and other organs that are used to control gaseous exchange and rate of transpiration.
6. Blue-green algae are included in the group ____:
[A] Protozoa
[B] Eubacteria
[C] Fungi
[D] Cyanobacteria
Show Answer
Correct Answer: D [Cyanobacteria]
Notes:
Cyanobacteria, also known as blue green algae, are single-celled and belong to the family of Prokaryotes. That means, they do not have a well defined cell nucleus. The ability of cyanobacteria to perform oxygenic photosynthesis is thought to have converted the early reducing atmosphere into an oxidizing one, which dramatically changed the composition of life forms on Earth by stimulating biodiversity and leading to the near-extinction of oxygen-intolerant organisms.
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. Silk worms feed on
____:
[A] Basil leaves
[B] Mulberry leaves
[C] Curry leaves
[D] Rose leaves
Show Answer
Correct Answer: B [Mulberry leaves]
Notes:
Silk worms are the larva of a moth (Bombyx mori) native to Asia that spins a cocoon of fine, strong, lustrous fiber that is the source of commercial silk. Silkworms feed on the leaves of the mulberries (genus- Morus) and sometimes on the Osage orange (Maclura pomifera).
9. Consider the following functions of bile juice released from the liver:
- It makes the food coming from the stomach alkaline
- It converts proteins into amino acids
- It breaks down fats into smaller globules
Which of the above statements is / are correct?
[A] Only 1
[B] Only 2 and 3
[C] Only 1 and 3
[D] All Are Correct Statements
Show Answer
Correct Answer: C [Only 1 and 3]
Notes:
Bile or gall is a dark green to yellowish brown fluid, produced by the liver that aids the digestion of lipids in the small intestine. It neutralizes the acid in food to provide the alkaline conditions needed in the small intestine. Besides, it breaks down large fat globules into smaller globules so that the pancreatic enzymes can easily act on them. This process is known as emulsification of fats. It does not convert proteins into amino acids.
10. 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.
