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. The exceptionally low melting point of mercury can be explained on the basis of which of the following explanations?
1. Mercury has completely filled-up atomic orbitals
2. In mercury, the binding energy of outer electrons (towards nucleus) is highest and no electron is available to participate in metallic bond formation
Choose the correct option from the codes given below:
[A] Only 1 is correct
[B] Only 2 is correct
[C] Both 1 & 2 are correct
[D] Neither 1 nor 2 is correct
Show Answer
Correct Answer: C [ Both 1 & 2 are correct]
Notes:
Mercury belongs to the zinc group of elements in the periodic table, which comprises zinc, cadmium and mercury. They all have completely filled-up atomic orbitals. It becomes difficult to knock out these electron(s) from their orbitals and form metallic bonds. With its filled shell electron configuration it is very reluctant to form bonds even with other mercury atoms.
2. Hydrochloric acid is secreted by the cells lining the
____:
[A] Stomach
[B] Ileum
[C] Oral cavity
[D] Colon
Show Answer
Correct Answer: A [Stomach]
Notes:
The chief cells of the stomach secrete enzymes for protein breakdown (inactive pepsinogen and rennin). Hydrochloric acid activates pepsinogen into the enzyme pepsin, which then helps digestion by breaking the bonds linking amino acids, a process known as proteolysis.
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 of the following is not a connective tissue?
[A] Cardiac Muscle
[B] Areolar Tissue
[C] Compact Bone
[D] Adipose Tissue
Show Answer
Correct Answer: A [Cardiac Muscle]
Notes:
Connective tissue is a group of tissues in the body that maintain the form of the body and its organs and provide cohesion and internal support. Bone, ligaments, tendons, cartilage, and adipose (fat) tissue are examples of connective tissue. Cardiac muscle is an example of muscle tissue. It is so named because it is found in the heart.
5. Which one of the following elements is associated with teeth disorder?
[A] Chlorine
[B] Bromine
[C] Iodine
[D] Fluorine
Show Answer
Correct Answer: D [Fluorine]
Notes:
Fluorine is the element that is associated with teeth disorder because the presence of sodium fluoride in drinking water at the level of 2ppm may cause mottled enamel in teeth, skeletal fluorosis, and may be associated with cancer and other diseases. However, topically applied fluoride (toothpaste, dental rinses) has been shown to help reduce dental caries.
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. 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.
8. What is the Normal Blood Volume in human adult?
[A] 1 litre
[B] 3 litre
[C] 5 litre
[D] 7 litre
Show Answer
Correct Answer: C [5 litre]
Notes:
The average adult has a blood volume of roughly 4-5 to 5 litres, which is composed of plasma and several kinds of cells. By volume, the red blood cells constitute about 45% of whole blood, the plasma about 54.3%, and white cells about 0.7%.
9. To digest protein which of the enzyme is present in pancreatic juice?
[A] Pepsin
[B] Upes
[C] Trypsin
[D] Amaylase
Show Answer
Correct Answer: C [Trypsin]
Notes:
Trypsin is an enzyme that helps us digest protein. In the small intestine, trypsin breaks down proteins, continuing the process of digestion that began in the stomach. It may also be referred to as a proteolytic enzyme, or proteinase. Trypsin is produced by the pancreas in an inactive form called trypsinogen. The trypsinogen enters the small intestine through the common bile duct and is converted to active trypsin.
10. Which of the following is an endangered species?
[A] Gangetic dolphin
[B] Blue sheep
[C] Black buck
[D] Mithun
Show Answer
Correct Answer: B [Blue sheep]
Notes:
According to the Red list of 2012, Ganges River Dolphin is one of critically endangered species in India. Endangered species in India comprise large varieties of rare species of wild animals, aquatic animals and insects.