11. The saliva helps in the digestion of which of the following materials? (UPSC Prelims 1988)
[A] Starch
[B] Proteins
[C] Fibers
[D] Fats
Show Answer
Correct Answer: A [Starch]
Notes:
The digestive functions of saliva include moistening food, and helping to create a food bolus, so it can be swallowed easily. Saliva contains the enzyme amylase that breaks some starches down into maltose and dextrin. Thus, digestion of food occurs within the mouth, even before food reaches the stomach.
12. Which of the following is the name given to the Inspection and dissection of a body after death in human beings as for determination of cause of death? (UPSC Prelims 1988)
[A] Autopsy
[B] Autotomy
[C] Autoesism
[D] Autograft
Show Answer
Correct Answer: A [Autopsy]
Notes:
An autopsy is a surgical procedure that consists of a thorough examination of a corpse by dissection to determine the cause, mode and manner of death or to evaluate any disease or injury that may be present for research or educational purposes.
13. Which one of the following organisms can serve as a biofertiliser for rice crop? (UPSC Prelims 2000)
[A] Blue-green algae
[B] Rhizobium sp
[C] Mycorrhizal fungi
[D] Azotobacter sp
Show Answer
Correct Answer: A [Blue-green algae]
Notes:
Blue green algae is used as a biofertilizer in rice crop. Blue green algae has the nitrogen fixing ability which enhances the production of rice. Blue–green algae are not algae at all, but types of bacteria called cyanobacteria that are normally present in many lakes.
14. In which of the following Alpha-keratin, a protein is present? (UPSC Prelims 2002)
[A] Blood
[B] skin
[C] wool
[D] eggs
Show Answer
Correct Answer: B [skin]
Notes:
Alpha-keratin, or α-keratin, is a type of keratin found in vertebrates. This protein is the primary component in hairs, horns, mammalian claws, nails and the epidermis layer of the skin. α-keratin is a fibrous structural protein, meaning it is made up of amino acids that form a repeating secondary structure.
15. How do small molecules pass through the outer membrane of mitochondria?
[A] Carrier protein
[B] Channels
[C] Porins
[D] ATP pump
Show Answer
Correct Answer: C [Porins]
Notes:
The outer membrane is a relatively simple phospholipid bilayer made up of protein structures called porins. This makes it permeable to molecules of about 10 kilodaltons or less.
16. In which part of the body cholesterol is synthesized?
[A] Pancreas
[B] Liver
[C] Spleen
[D] Stomach
Show Answer
Correct Answer: B [Liver]
Notes:
Cholesterol is a type of Lipid or the fat present in blood. The majority of the cholesterol consumed by the human body on a daily basis is synthesised by Liver.
17. In cell culture, the measles virus can lead to which of the following?
[A] nuclear pyknosis
[B] transformation of cells
[C] syncytium formation
[D] rounding and aggregation of cells
Show Answer
Correct Answer: C [syncytium formation]
Notes:
In cell culture, the measles virus can lead to syncytium formation.
18. Which of the following oncogenic virus was first detected?
[A] Rous sarcoma virus
[B] Epstein-Barr virus
[C] Herpes simplex virus type 2
[D] Human T cell leukaemia virus
Show Answer
Correct Answer: A [Rous sarcoma virus]
Notes:
Rous sarcoma virus(RSV) was discovered in 1911 by Peyton Rous.
19. Where does reduction division take place in pteridophytes?
[A] Prothallus is formed
[B] Gametes are formed
[C] spores are formed
[D] sex organs are formed
Show Answer
Correct Answer: C [spores are formed]
Notes:
In ferns, the main plant body is sporophytic. Its leaves, known as sporophylls, have sporangia on them. Reduction division takes place in these spores, producing many spores from them. Spores are the initials of the gametophyte stage.
20. Which of the following is the smallest gymnosperm?
[A] Cycas
[B] Pinus
[C] Zamia
[D] Gnetum
Show Answer
Correct Answer: C [Zamia]
Notes:
The smallest gymnosperm is Zamia pygmia which reaches a height of 25 cm.