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 are the limitations of Bohr’s model of atom?
[A] it cannot explain spectrum of atoms containing more than one electron
[B] it cannot explain the Zeeman effect
[C] it cannot explain the Stark effect
[D] All of the above
Show Answer
Correct Answer: D [All of the above]
Notes:
Bohr’s model of atom cannot explain spectrum of atoms containing more than one electron. Also, it cannot explain the Zeeman effect i.e. splitting of spectral line in presence of magnetic field. It also fails to explain Stark effect i.e. splitting of spectral line in presence of electric field.
2. What are the products of the reaction when metal carbonate reacts with an acid?
[A] Salt and Hydrogen
[B] Carbon dioxide
[C] Salt, Carbon dioxide and water
[D] Salt, Carbon dioxide and Hydrogen
Show Answer
Correct Answer: C [Salt, Carbon dioxide and water]
Notes:
All metal carbonates and hydrogen carbonates react with acids to give a corresponding salt, carbon dioxide and water. Limestone, chalk and marble are different forms of calcium carbonate.
3. 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.
4. Who discovered electron?
[A] J. chadwick
[B] Ernest Rutherford
[C] J.J.Thomson
[D] E.Goldstein
Show Answer
Correct Answer: C [J.J.Thomson]
Notes:
In 1897, J.J. Thomson discovered the electron by experimenting with a Crookes, or cathode ray, tube. He demonstrated that cathode rays were negatively charged.
5. 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.
6. An eardrum is absent in ____:
[A] Snakes
[B] Toads
[C] Turtles
[D] Tuatara
Show Answer
Correct Answer: A [Snakes]
Notes:
The ear has three main parts: the outer, middle and inner ear. The outer ear consists of the pinna and the auditory canal. The middle ear is filled with air and contains three tiny bones called ossicles – the anvil, hammer and stirrup. The inner ear contains the semicircular canals and the cochlea. Eardrum is the membrane of middle ear. Snakes have fully developed inner ear structures but no eardrum.
7. Grey hair is caused due to
____:
[A] Aging of epidermal cells
[B] Death of dermal cells
[C] Loss of sebum in epidermal cells
[D] Loss of melanin in epidermal cells
Show Answer
Correct Answer: D [Loss of melanin in epidermal cells]
Notes:
The hair follicles have pigment cells that make melanin, a chemical that gives the hair its color. As one ages, these cells start to die. Without pigment, new hair strands grow in lighter and take on various shades of gray, silver, and eventually white.
8. What is commonly known as white plague?
[A] Typhoid
[B] Malaria
[C] Tuberculosis
[D] Plague
Show Answer
Correct Answer: C [Tuberculosis]
Notes:
Tuberculosis caused by Mycobacterium tuberculie which primarily affects lungs although can affect other body too while early 19th century was called ‘white plague’ because of the large number of the people dying of its infection.
9. In male sharks, Claspers are found attached to
____:
[A] Anal fin
[B] Ventral fin
[C] Pectoral fin
[D] Pelvic fin
Show Answer
Correct Answer: D [Pelvic fin]
Notes:
Claspers are organs found in male elasmobranchs. Each male has two claspers. They are located along the inner side of the shark or ray’s pelvic fin and are used in reproduction. During mating, the male deposits his sperm into the female’s cloaca (the opening that serves as the entrance to the uterus, intestine and urinary tract) via grooves that lie in the upper side of the claspers.
10. What are female gametes called as?
[A] Zygote
[B] Sperms
[C] Embryo
[D] Ova
Show Answer
Correct Answer: D [Ova]
Notes:
Female gametes are also called eggs or ova. They are created during the cellular reproduction process known as meiosis. The resulting gamete cell is a haploid cell. When the two haploid cells, the egg and sperm, fuse together during fertilization, the result is a diploid cell called a zygote.