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 is known as the fourth state of matter?
[A] Bose-Einstein condensates
[B] Plasma
[C] Gas
[D] Liquid
Show Answer
Correct Answer: B [Plasma]
Notes:
Plasma consists of freely moving ions and electrons. It forms when energy supplied to a gas causes ionization. Plasma is present in stars, including the Sun. It conducts electricity and responds to magnetic fields. Irving Langmuir coined the term “plasma” in 1928. Plasma is different from solids, liquids, and gases due to its unique electrical properties.
2. Which of the following elements is present in heavy water?
[A] Heavy Oxygen
[B] Heavy Hydrogen
[C] Heavy Chlorine
[D] Heavy Nitrogen
Show Answer
Correct Answer: B [Heavy Hydrogen ]
Notes:
Heavy water is water that contains heavy hydrogen or deuterium. Deuterium differs from the hydrogen usually found in water, protium, in that each atom of deuterium contains a proton and a neutron. Heavy water may be deuterium oxide, D2O or it may be deuterium protium oxide, DHO.
3. Chicken Pox is caused by which micro-organism?
[A] Virus
[B] Bacteria
[C] Protozoa
[D] Fungus
Show Answer
Correct Answer: A [Virus]
Notes:
Chickenpox, also known as varicella, is a highly contagious infection caused by the varicella zoster virus. The disease results in a characteristic skin rash that forms small, itchy blisters, which eventually scab over. It is an airborne disease which spreads easily through the coughs and sneezes of an infected person.
4. In the grass lands, trees do not replace the grasses as a part of an ecological succession because of ____:
[A] Limited sun light and paucity of nutrients
[B] Insect and fungi
[C] Water limits and fire
[D] None of the above
Show Answer
Correct Answer: C [Water limits and fire]
Notes:
Ecological succession is unidirectional progressive process of development in an ecosystem or biome. Grass ecosystems are an early stage of succession in regions where the mature ecosystems are forests. However, grass ecosystems are climax ecosystems in grassland regions, where there is not enough rainfall to support a forest. Due to limiting factors such as water scarcity and forest fire, a grassland ecosystem changes to a desert ecosystem. The ecological succession of grassland is desert.
5. The colour change in the Chameleon is due to the presence of ____:
[A] Chromatophore
[B] Haemoglobin
[C] Chlorophyll
[D] Pneumatophore
Show Answer
Correct Answer: A [Chromatophore]
Notes:
Chameleons have specialized cells, chromatophores, which contain pigments in their cytoplasm, in three layers below their transparent outer skin. Dispersion of the pigment granules in the chromatophores sets the intensity of each color. Chromatophores contain pigments and reflect light, which are responsible for creating coloration. In chameleons, there are four types of chromatophores: xanthophores, erythrophores, iridiophores, and melanophores (Cooper and Greenberg, 1992).
6. Mycobacterium leprae is a ____:
[A] Bacillus
[B] Spiral
[C] Coccus
[D] Spore
Show Answer
Correct Answer: A [Bacillus]
Notes:
Mycobacterium leprae is a bacillus (rod-shaped) bacterium that causes leprosy, also known as “Hansen’s disease”, which is a chronic infectious disease that damages the peripheral nerves and targets the skin, eyes, and muscles, upper respiratory tract, and nasal mucosa (lining of the nose).
7. 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).
8. Which of the following vitamins help in the absorption of calcium?
[A] Vitamin A
[B] Vitamin B
[C] Vitamin C
[D] Vitamin D
Show Answer
Correct Answer: D [Vitamin D]
Notes:
Vitamin D is essential in helping the body absorb and use calcium; in fact, the body cannot absorb calcium at all without some vitamin D. Vitamin D helps our intestines absorb calcium from the food we eat and helps build stronger bones.
9. The largest cells in mammalian blood are ____:
[A] Monocytes
[B] Lymphocytes
[C] Erythrocytes
[D] Basophils
Show Answer
Correct Answer: A [Monocytes]
Notes:
Various components of blood are: Plasma, Erythrocytes (Red Blood Cells), Leucocytes (White Blood Cells) and Thrombocytes/Platelets. Monocytes, also known as macrophages, are the largest blood cells in most mammals, measuring 10-15 cm in diameter. They are leucocytes. Their nuclei are kidney-shaped and cytoplasm is abundant.
10. Which of the following statements is not correct regarding the ‘Bombay blood group’?
[A] It is deficient in expressing H antigen
[B] It has neither A nor B antigen
[C] It was first discovered in 1952 by Dr. Y.M. Bhende
[D] A person with this blood group may receive blood only from a person with O blood group
Show Answer
Correct Answer: D [A person with this blood group may receive blood only from a person with O blood group]
Notes:
Hh or the Bombay blood group, is a rare blood type. This blood phenotype was first discovered in Bombay, now known as Mumbai, by Dr. Y. M. Bhende in 1952. It is mostly found in South Asia (India, Bangladesh, Pakistan) and parts of Middle East such as Iran. Individuals with the rare Bombay phenotype (hh) do not express H antigen (also called substance H), the antigen which is present in blood group O. For this reason people who have Bombay phenotype can donate red blood cells to any member of the ABO blood group system but they cannot receive blood from any member of the ABO blood group system but only from other people who have Bombay phenotype.