11. Most of the desert plants bloom during night time due to which of the following reasons? (UPSC Prelims 1995)
[A] their blooming is controlled by low temperature
[B] they are sensitive to the phases of the moon
[C] the desert insects eat away flowers during day time
[D] the desert insects are active during night time
Show Answer
Correct Answer: D [the desert insects are active during night time]
Notes:
In desert conditions, most of the activity of the plants and animals happens during the night because of very high temperature in the day time. The desert insects make themselves active and pollinate the flowers at night. To attract the insects, most of the desert plants bloom during the night.
12. Which of the following is the major component of honey? (UPSC Prelims 1997)
[A] Glucose
[B] sucrose
[C] maltose
[D] fructose
Show Answer
Correct Answer: D [fructose]
Notes:
Fructose comprises the major portion of honey – about 82%. The carbohydrates present are the monosaccharides fructose (38.2%) and glucose (31%); and disaccharides (~9%) sucrose, maltose, isomaltose, maltulose, turanose and kojibiose.
13. Ticks and mites belongs to which of the following classes? (UPSC Prelims 2002)
[A] Arachnids
[B] Crustaceans
[C] Insects
[D] Myriapods
Show Answer
Correct Answer: A [Arachnids]
Notes:
The order Acarina (class Arachnida) includes mites and ticks. Members of this order differ from other arachnids in that the body is not segmented, and the cephalothorax and abdomen are combined into one body region. Larval mites and ticks have three pairs of legs, whereas nymphs and adults have four pairs.
14. 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.
15. Which among the following is NOT a major function of the plant hormone Abscisic Acid?
[A] Abscission of Leaves
[B] Inhibition of growth and maintenance of the dormancy of buds
[C] Inhibition of germination in dormant seeds
[D] All of them are major functions of Abscisic Acid
All of above are major functions of Abscisic acid
Show Answer
Correct Answer: A [Abscission of Leaves]
Notes:
This question is might have trapped almost all of you. The option A which etymologically linked to the question would trap you. We should note that Abscisic acid plays any significant role in leaf abscission is unfortunately not proved. The hormone is also called Dormin and its major functions are inhibition. But abscission of leaves is something better explained by Auxin-ethylene roles. Kindly surf the web and try to find out, if I am right. Inhibition of growth and maintenance of the dormancy of buds are the most striking effects of ABA. ABA activity alone is not enough to keep the dormancy of buds up in the long term though. Further, ABA is an efficient inhibitor of germination and occurs in high concentrations in dormant seeds. The role ABA has during the abscission of fruits and leaves is largely unknown. Though both cases seem to be governed by similar mechanisms (Auxin-Ethylene to a great extent) has ABA nearly no effect on the abscission of leaves while it shows a clear effect on fruit abscission. The role of Abscisic acid in abscission was a pharmacological artifact…applied AbA often induces ethylene biosynthesis.
16. What is the translucent fluid part of the cytoplasm called?
[A] Cell protein
[B] Cytosol
[C] Matrix
[D] Organelles
Show Answer
Correct Answer: B [Cytosol]
Notes:
Cytosol is the liquid found inside cells. It is a water-based solution that floats organelles, proteins, and other cell structures.
17. Where are glycolipids located in the plasma membrane?
[A] Inner leaflet of the plasma membrane
[B] The outer leaflet of the plasma membrane
[C] evenly distributed in inner and outer leaflets
[D] It varies by cell type
Show Answer
Correct Answer: B [The outer leaflet of the plasma membrane]
Notes:
Glycolipids are found in the outermost leaflet of the plasma membrane, their carbohydrate portions visible on the cell surface.
18. Which of the following protects the body from infectious disease?
[A] Leukocytes
[B] Red Blood Cells
[C] Endoplasmic Reticulum
[D] Golgi Bodies
Show Answer
Correct Answer: A [Leukocytes]
Notes:
White blood cells (WBC), also called leukocytes or leukocytes. Immune system cells that help protect our body from infectious diseases.
19. Who discovered nucleus of cell wall?
[A] Theodor Boveri
[B] Robert Brown
[C] Albert von Kolliker
[D] Robert Hooke
Show Answer
Correct Answer: B [Robert Brown]
Notes:
Robert Brown discovered the nucleus in the cell in 1831. The nucleus is a protoplasmic body in eukaryotic cells. It is covered by a double membrane that contains the hereditary details.
20. Which of the following virus is covered?
[A] Adeno
[B] Herpes
[C] Polio
[D] None of these
Show Answer
Correct Answer: B [Herpes]
Notes:
The Herpesviridae are a large family of DNA viruses. It causes infections and some diseases in animals, including humans. Members of this family are also known as herpesviruses.