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. What percentage of carbon is present in steel?
[A] 0.0 to 2.5
[B] 2.5 to 5.0
[C] 5.0 to 7.5
[D] 7.5 to 10.0
Show Answer
Correct Answer: A [0.0 to 2.5 ]
Notes:
Steel is an alloy made by combining iron and other elements, the most common of these being carbon. When carbon is used, its content in the steel is between 0.2% and 2. 1% by weight, depending on the grade. Other alloying elements sometimes used are manganese, chromium, vanadium and tungsten. Carbon and other elements act as a hardening agent, preventing dislocations in the iron atom crystal lattice from sliding past one another.
3. Both, haemoglobin and myoglobin require ____ for formation:
[A] Vitamin A
[B] Vitamin B12
[C] Iron
[D] Calcium
Show Answer
Correct Answer: C [Iron]
Notes:
Haemoglobin is called as tetrameric hemoprotein, while myoglobin is called monomeric protein. Haemoglobin is found systematically all over the body, while myo-globin is found in muscles tissues only. The body requires iron for the synthesis of its oxygen transport proteins, in particular hemo-globin and myoglobin.
4. The wing of a bat and the wing of a bird are the examples of ____ limbs:
[A] Heterogeneous
[B] Homogenous
[C] Homologous
[D] Analogous
Show Answer
Correct Answer: D [Analogous]
Notes:
The wings of insects, bats and birds, that evolved independently in each lineage separately after diverging from an ancestor without wings, are examples of analogous organs. Analogous organs are the opposite of homologous organs, which have similar functions but different origins.
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. The release of which of the following into ponds and wells helps in controlling mosquitoes?
[A] Snail
[B] Crab
[C] Dogfish
[D] Gambusia fish
Show Answer
Correct Answer: D [Gambusia fish]
Notes:
The Gambusia fish, also known as larvivorous stagnant water fish. It feeds on the larvae of mosquitoes. So it helps in controlling their population. It is also called ‘mosquito fish’ and is being used as a biological control measure. Hence, a check on malaria and other vector borne diseases like even dengue.
7. One of the best solutions to get rid of non-biodegradable wastes is ____:
[A] Burning
[B] Dumping
[C] Burying
[D] Recycling
Show Answer
Correct Answer: D [Recycling]
Notes:
The best way of getting rid of non-biodegradable waste such as plastic is by recycling them. Recycling is the process of converting waste materials into new materials and objects. The recovery of energy from waste materials is often included in this concept. Recycling is a key component of modern waste reduction and is the third component of the “Reduce, Reuse, and Recycle” waste hierarchy. Burning may release toxic gas into the atmosphere. Burying and dumping will hardly solve anything because of their very long life of self decomposition.
8. Consider the following hormones:
- Estrogen
- Progesterone
- Testosterone
Which of the above is/are classified as female hormones?
[A] (i) and (iii)
[B] (i) and (ii)
[C] (ii) and (iii)
[D] Only (iii)
Show Answer
Correct Answer: B [(i) and (ii)]
Notes:
There are several hormones in females which are naturally produced and secreted by the glands of the endocrine system. Among them, estrogen, and progesterone are secreted for the influence on a woman’s reproductive health and are termed as female sex hormones. Estrogen and progesterone are made by the ovaries.
9. 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).
10. Element that is not found in blood is ___:
[A] Copper
[B] Iron
[C] Chromium
[D] Magnesium
Show Answer
Correct Answer: C [Chromium ]
Notes:
In the blood the key minerals are iron, copper, zinc, sodium, potassium, calcium and magnesium. Minerals constitute important part of blood plasma that constitutes almost 55% of blood. In the blood, iron is found in larger amounts than any other mineral.