11. With reference to classification of the flora and fauna, the meaning of term “Taxon” is __?
[A] A group of same species
[B] A group of organisms with same chromosome number
[C] A group of category of organisms
[D] A group of same genera
Show Answer
Correct Answer: C [ A group of category of organisms]
Notes:
In biology, a taxon (plural taxa; back-formation from taxonomy) is a group of one or more populations of an organism or organisms seen by taxonomists to form a unit.
12. Which of the following is the function of the liver? (UPSC Prelims 1979).
[A] Promote digestion of food
[B] Promote respiration
[C] Store glucose as glucogen
[D] None of these
Show Answer
Correct Answer: C [Store glucose as glucogen]
Notes:
The liver’s main job is to filter the blood coming from the digestive tract, before passing it to the rest of the body. The primary functions of the liver are:
• Bile production and excretion
• Excretion of bilirubin, cholesterol, hormones, and drugs
• Metabolism of fats, proteins, and carbohydrates
• Enzyme activation
• Storage of glycogen, vitamins, and minerals
• Synthesis of plasma proteins, such as albumin, and clotting factors
13. The sequencing of the entire genome (the totality of all genes) of an organism was completed in 1996. Which one of the following was that organism? (UPSC Prelims 1997)
[A] Albino mouse
[B] yeast
[C] human being
[D] Plasmodium vivax
Show Answer
Correct Answer: D [Plasmodium vivax]
Notes:
Plasmodium vivax is a protozoal parasite and a human pathogen. This parasite is the most frequent and widely distributed cause of recurring malaria.
14. Which one of the following statements regarding starch and cellulose is not correct? (UPSC Prelims 1998)
[A] Both of them are of plant origin
[B] Both of them are polymers
[C] Both of them give colour with iodine
[D] Both of them are made up of glucose molecules
Show Answer
Correct Answer: C [Both of them give colour with iodine]
Notes:
Starch and cellulose both are plant origin. Starch deposits in plant cells, whereas cellulose is most important constituent of plant cell wall. Both starch and cellulose are polymers. Starch is branched polymer of α – D – glucose unit linked by α – 1, 4 glycosidic bond. Cellulose is a linear polymer of β – D – glucose unit. Glucose molecules are present in both starch and cellulose. Amylose in starch is responsible for the formation of deep blue colour in the presence of iodine but cellulose does not give any colour at the treatment with iodine, because amylose is absent in cellulose.
15. “Athlete’s Foot” is a disease caused by which of the following microorganisms? (UPSC Prelims 2001)
[A] Bacteria
[B] Fungus
[C] Protozoan
[D] Nematode
Show Answer
Correct Answer: B [Fungus]
Notes:
It is a member of the group of diseases known as tinea. Athlete’s foot is caused by a number of different fungi, including species of Trichophyton, Epidermophyton, and Microsporum. The condition is typically acquired by coming into contact with infected skin, or fungus in the environment.
16. Which vitamin is also called as ascorbic acid?
[A] Vitamin A
[B] Vitamin C
[C] Vitamin D
[D] Vitamin K
Show Answer
Correct Answer: B [Vitamin C]
Notes:
Vitamin C is also called as ascorbic acid. Deficiency in vitamin C leads to scurvy. Chemical formula of vitamin C is C6H8O6.
17. Who among the following discovered Vitamin E?
[A] Evans and Bishop
[B] Henrik Dam
[C] Harry Holmes and Ruth Corbet
[D] Sir Edward Mellanby
Show Answer
Correct Answer: A [Evans and Bishop]
Notes:
Vitamin E was discovered by Evans and Bishop in 1922. Work in the 1930s revealed the chemical structure and biological function of alpha-tocopherol.
18. Which statement is true for the capsid?
[A] It consists of capsomeres
[B] This the outermost layer of most viruses
[C] It protects genetic material
[D] All of the above
Show Answer
Correct Answer: D [All of the above]
Notes:
A capsid is the protein shell of a type of virus, which encloses its genetic material.
19. Who among the following discovered the cell wall?
[A] Robert Hooke
[B] Boveri
[C] J Rhodin
[D] Van Beneden
Show Answer
Correct Answer: A [Robert Hooke]
Notes:
A plant cell wall was first observed and named by Robert Hooke in 1665.
20. In anaerobic respiration, glucose is broken down into what?
[A] ethyl alcohol
[B] carbon dioxide
[C] energy
[D] All of the above
Show Answer
Correct Answer: D [All of the above]
Notes:
Glucose breaks down into ethyl alcohol, carbon dioxide, and energy.
Glucose → Alcohol + Carbon dioxide + Energy
