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
31. A specific function of light energy in the process of photosynthesis is to ____:
[A] Reduce CO2
[B] Absorb water
[C] Formation of oxygen
[D] Activate chlorophyll
Show Answer
Correct Answer: D [Activate chlorophyll]
Notes:
The process of photosynthesis occurs when green plants use the energy of light to convert carbon dioxide (CO2) and water (H2O) into carbohydrates. Light energy is absorbed by chlorophyll, a photosynthetic pigment of the plant, while air containing carbon dioxide and oxygen enters the plant through the leaf stomata.
32. Linseed is obtained from ____:
[A] Sesame
[B] Castor
[C] Flax
[D] Groundnut
Show Answer
Correct Answer: C [Flax]
Notes:
Linseed are the seeds of the flax plant, which are the source of linseed oil and linseed cake. Flax is a member of the genus Linum in the family Linaceae. Linseed is one of the most potent sources of omega- 3 fatty acids found in nature.
33. Which of the following is also known as the Biochemical Laboratory of the Human Body?
[A] Small Intestine
[B] Pancreas
[C] Brain
[D] Liver
Show Answer
Correct Answer: D [Liver]
Notes:
Liver is considered as the biochemical laboratory of the human body. It synthesizes and secretes at least four important hormones and has a wide range of functions, including detoxification of various metabolites, protein synthesis, and the production of biochemicals necessary for digestion. It is tied to all bodily processes because it is responsible for filtration of all incoming foods and fluids. Some of the most important functions (among 500 functions carried out by it) are:
• Metabolizes proteins, fats, and carbohydrates, thus providing energy and nutrients
• Stores vitamins, minerals, and sugars
• Filters the blood and helps remove harmful chemicals and bacteria
• Creates bile which breaks down fats Helps to assimilate and store fat soluble vitamins (A, E, D, K); etc.
34. Where does glucose breaks down into pyruvate?
[A] Golgi bodies
[B] Cytoplasm
[C] Protoplasm
[D] Chloroplast
Show Answer
Correct Answer: B [Cytoplasm]
Notes:
During glycolysis, glucose is broken down in ten steps to two molecules of pyruvate in cytoplasm (in the cellular matrix called cytosol). It then enters the mitochondria where it is oxidised through the tricarboxylic acid cycle to carbon dioxide and water.
35. Liver is a rich source of _____:
[A] Minerals
[B] Fat soluble vitamins
[C] Proteins
[D] Sugars
Show Answer
Correct Answer: C [Proteins ]
Notes:
In general, liver is a good source of vitamin A, iron, zinc, copper and manganese, and a very good source of protein. There are twenty grams of protein in a single slice of liver.
36. Which of the following cell organelle is present only in plant cell?
[A] Vacuole
[B] Mitochondria
[C] Cell membrane
[D] Cell wall
Show Answer
Correct Answer: D [Cell wall]
Notes:
Cell wall is found in plants, bacteria, fungi, algae, and some archaea. Animal cells do not have cell walls, nor do protozoa. It is a structural layer situated outside the cell membrane that provides the cell with both structural support and protection, and also acts as a filtering mechanism.
37. The upper part of the respiratory tract is provided with small hair-l ike structures called ____:
[A] Bronchi
[B] Cilia
[C] Villi
[D] Alveoli
Show Answer
Correct Answer: B [Cilia]
Notes:
The majority of the upper respiratory epithelium is lined with cilia, small hair-like structures that move together like oars to push the mucus and its trapped contents to the throat, where it is swallowed. Each cell has about 300 cilia.
38. By which process, a tadpole develops into an adult frog?
[A] Budding
[B] Embedding
[C] Fertilisation
[D] Metamorphosis
Show Answer
Correct Answer: D [Metamorphosis]
Notes:
Metamorphosis is a process by which animals undergo extreme, rapid physical changes some time after birth. Commonly known examples of metamorphosis include the process undergone by most insects, and the transformation of tadpoles into frogs. Hormones called molting and juvenile hormones, which are not species specific, apparently regulate the changes.
39. During exhalation, the ribs ____:
[A] Move outwards
[B] Move downwards
[C] Move upwards
[D] Do not move at all
Show Answer
Correct Answer: B [Move downwards]
Notes:
Breathing is the process in which air moves in and out of the lungs with the help of various respiratory organs. The process of taking in air rich in oxygen is called inhalation. Similarly, the process of giving out air rich in carbon dioxide is called exhalation. When we inhale, the ribs move up and outwards while the diaphragm moves down. An exact opposite movement occurs during exhalation when the ribs move down and inwards while the diaphragm moves up.
40. Number of teeth which are replaced in man are _____:
[A] 12
[B] 16
[C] 20
[D] 32
Show Answer
Correct Answer: A [12]
Notes:
Deciduous teeth are the first set of teeth in the growth development of humans and many other mammals. The deciduous teeth are: incisors
[D]; molars (6); and canine
[B]. So there are 12 teeth which get replaced by the age of 12 years when only permanent teeth remain.