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. Who among the following scientists had discovered Radium?
[A] Marie Sklodowska-Curie and Pierre Curie
[B] André-Louis Debierne
[C] Kasimir Fajans
[D] Oswald Helmuth Göhring
Show Answer
Correct Answer: A [Marie Sklodowska-Curie and Pierre Curie ]
Notes:
Radium is a chemical element with the symbol Ra and atomic number 88. Radium was discovered by Marie Sklodowska Curie, a Polish chemist, and Pierre Curie, a French chemist, in 1898.
2. How the Cast Iron is different from Wrought Iron?
- Cast iron have higher carbon content than wrought iron
- Cast iron are more ductile compared to wrought iron
- Wrought iron is more stable, pure and stronger, compared to cast iron
Select the correct option from the codes given below:
[A] 3 Only
[B] 1 and 3 Only
[C] 2 and 3 Only
[D] 1,2 and 3
Show Answer
Correct Answer: B [ 1 and 3 Only]
Notes:
Second statement is wrong because wrought iron is more ductile compared to cast iron
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. 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.
5. 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.
6. Wilting of plants occurs due to excessive ____:
[A] Respiration
[B] Glutation
[C] Absorption
[D] Transpiration
Show Answer
Correct Answer: D [Transpiration]
Notes:
Plant wilting occurs after excessive loss of water by transpiration and lesser absorption. i.e. rate of transpiration exceeds rate of water absorption. On a hot day, plants transpire heavily and cannot absorb water speedily to keep pace with transpiration loss, even when there is enough water.
7. Which of the following is/are agent(s) of infection?
[A] Physical contact
[B] Water
[C] Vectors
[D] All of the above
Show Answer
Correct Answer: D [All of the above ]
Notes:
Infection is the invasion of an organism’s body tissues by disease-causing agents, their multiplication, and the reaction of host tissues to the infectious agents and the toxins they produce. Infectious diseases can be spread from one person to another, for example through contact with bodily fluids, by aerosols (through coughing and sneezing), or via a vector, for example a mosquito.
8. Osteocytes are found in ____:
[A] Blood
[B] Bone
[C] Lymph
[D] Cartilage
Show Answer
Correct Answer: B [Bone]
Notes:
An osteocyte, a star shaped cell, is the most commonly found cell in mature bone, and can live as long as the organism itself. Osteocytes are networked to each other via long cytoplasmic extensions that occupy tiny canals called canaliculi, which are used for exchange of nutrients and waste through gap junctions. The space that an osteocyte occupies is called a lacuna.
9. Which among the following has open circulatory system?
I. Cockroach
II. Human
III. Prawn
[A] I and II
[B] I and III
[C] II and III
[D] Only III
Show Answer
Correct Answer: B [I and III]
Notes:
Cockroach and prawns have open circulatory system in which the blood is not confined within blood vessels. The blood bathes the organs and tissues directly. Open circulatory systems pump blood into a hemocoel with the blood diffusing back to the circulatory system between cells. Blood is pumped by a heart into the body cavities, where tissues are surrounded by the blood. The open circulatory system is common to molluscs and arthropods.
10. Biodegradable wastes can usually be converted into useful substances with the help of ____:
[A] Bacteria
[B] Viruses
[C] Nuclear proteins
[D] Radioactive substances
Show Answer
Correct Answer: A [Bacteria]
Notes:
Bacteria are the most abundant organisms which play important role in the decomposition of organic matter. Majority of bacteria involved in decomposition of organic matter are heterotrophs and autotrophs are least in proportion which are not directly involved in organic matter decomposition.