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 structures are present in the throat to prevent the air passage from collapsing?
[A] Rings of cartilage
[B] Rings of muscle
[C] Rings of bone
[D] Rings of connective tissue
Show Answer
Correct Answer: A [Rings of cartilage]
Notes:
Rings of cartilage are present in the throat, specifically in the trachea or windpipe, to ensure that the air passage does not collapse. These semi-circular rings provide the necessary structural support to keep the airway open regardless of pressure changes that occur during breathing. This is very important for maintaining a clear, open path for air to flow into our lungs for respiration.
2. Intensive cultivation refers to ___:
[A] Raising production by intensive use of existing land
[B] Raising production by large scale use of imported inputs
[C] Production with intensive use of labour
[D] Production with intensive use of fertilizer
Show Answer
Correct Answer: A [Raising production by intensive use of existing land]
Notes:
Intensive farming is an agricultural intensification and mechanization system that aims to maximize yields from available land through various means, such as heavy use of pesticides and chemical fertilizers. It is characterized by a low fallow ratio, higher use of inputs such as capital and labour, and higher crop yields per unit land area.
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. Jaundice is a symptom of disease of
____:
[A] Kidney
[B] Liver
[C] Pancreas
[D] Thyroid
Show Answer
Correct Answer: B [Liver]
Notes:
Jaundice is a yellowish pigmentation of the skin, the conjunctival membranes over the sclerae (whites of the eyes), and other mucous membranes caused by hyperbilirubinemia. Concentration of bilirubin in blood plasma does not normally exceed 1 mg/dL (>17?mol/L). A concentration higher than 1.8 mg/ dL (>30?mol/L) leads to jaundice. Jaundice is often seen in liver disease such as hepatitis or liver cancer.
5. 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.
6. When we touch leaves of “Touch me not plant”, they close, these movements are called ____:
[A] Seismonastic movements
[B] Photonastic movements
[C] Nyctinastic movements
[D] Chemonastic movements
Show Answer
Correct Answer: A [Seismonastic movements]
Notes:
These types of mechanism have been termed seismonastic movements. The movement occurs when specific regions of cells lose turgor pressure, which is the force that is applied onto the cell wall by water within the cell vacuoles and other cell contents.
7. The vitamin which is very labile and easily destroyed during cooking as well as storage is vitamin ____:
[A] Vitamin D
[B] Vitamin C
[C] Vitamin K
[D] Vitamin B6
Show Answer
Correct Answer: B [Vitamin C]
Notes:
Vitamin C is quite unstable when cooked or stored improperly. It is very liable and easily destroyed during cooking as well as storage. It is a water-soluble and temperature-sensitive vitamin, so is easily degraded during cooking, and elevated temperatures and long cooking times have been found to cause particularly severe losses of vitamin C.
8. The pigment that gives human skin, hair and eyes their colour is called ____:
[A] Quinacridone
[B] Alizarin
[C] Melanin
[D] Phthalocyanine
Show Answer
Correct Answer: C [Melanin ]
Notes:
The pigment that gives human skin, hair, and eyes their color. Dark-skinned people have more melanin in their skin than light-skinned people have. Melanin is produced by cells called melanocytes. Everyone has the same number of melanocytes, but some people make more melanin than others.
9. How the rate of absorption of water through roots can be increased?
[A] Keeping the plants under the fan
[B] Keeping the plants in the dim light
[C] Keeping the plants in the shade
[D] Covering the plants with a polythene bag
Show Answer
Correct Answer: A [Keeping the plants under the fan]
Notes:
When a plant is placed under the fan, the speed of air is increased which leads to high rate of transpiration through the stomata. The increase in the rate of transpiration increases the water absorption also. As by keeping the plants under the fan, the transpiration process is boosted. Therefore, more amount of water and other minerals are absorbed by the plant roots from the soil.
10. 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).