11. Fertility of soil can be improved by which of the following methods? (UPSC Prelims 2000)
[A] Removing dead earthworms
[B] Adding dead earthworms
[C] Adding living earthworms
[D] Removing living earthworms and adding dead earthworms
Show Answer
Correct Answer: C [Adding living earthworms]
Notes:
Worms help to increase the amount of air and water that gets into the soil. They break down organic matter, like leaves and grass into things that plants can use. When they eat, they leave behind castings that are a very valuable type of fertilizer. Earthworms are like free farm help.
12. Which among the following is the method of growing plants in the absence of soil?
[A] Hydrology
[B] Hydrotectonics
[C] Hydroponics
[D] Hydrochronology
Show Answer
Correct Answer: C [Hydroponics]
Notes:
The method of growing plants in the absence of soil is called as hydroponics. The required suppliments to the plants are supplied through the mineral nutrient solutions.
13. 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.
14. Which of the following branch of biology deals with the study of behavioral aspects of animals?
[A] Myrmecology
[B] Palaeozoology
[C] Psychobiology
[D] Parazoology
Show Answer
Correct Answer: C [Psychobiology]
Notes:
Psychobiology is branch of biology which deals with the study of behavioral aspects of animals.
15. What is the basic unit of Classification?
[A] Genus
[B] Species
[C] Order
[D] Family
Show Answer
Correct Answer: B [Species]
Notes:
Species is the basic unit of classification. Species are known as the basic units of classification because individuals of species are closely related structurally and functionally and can interbreed freely.
16. Green Algae are known as__?
[A] Rhodophyceae
[B] Chlorophyceae
[C] Phaeophyceae
[D] Green tide
Show Answer
Correct Answer: B [Chlorophyceae]
Notes:
Algae is a Thalloid plant and autotrophic in nature. Mostly algae is aquatic and contains chlorophyll. Green algae is also known as Chlorophyceae.
17. Which of the following cell organelles contain RNA?
[A] Plastids
[B] Mitochondria
[C] Ribosomes
[D] Lysosomes
Show Answer
Correct Answer: C [Ribosomes]
Notes:
Ribosomes are small organelles that contain RNA and specific proteins within the cytoplasm.
18. Which of the following is a reducing sugar?
[A] β-methyl galactosidase
[B] Sucrose
[C] Gluconic acid
[D] Galactose
Show Answer
Correct Answer: D [Galactose]
Notes:
The dietary monosaccharides galactose, glucose and fructose are all reducing sugars.
19. The change from lysogeny to lymph is usually induced by?
[A] ultraviolet light
[B] chemicals
[C] irradiation
[D] all of these
Show Answer
Correct Answer: A [ultraviolet light]
Notes:
The change from lysogeny to lymph is usually induced by ultraviolet light. Lysogeny is a type of life cycle that occurs when a bacteriophage infects certain types of bacteria.
20. Which of the following is a parasitic alga?
[A] Vaucheria
[B] Polysiphonia
[C] Cephaleuros
[D] Batrachospermum
Show Answer
Correct Answer: C [Cephaleuros]
Notes:
Cephaleuros is a genus of parasitic thalloid green algae. It includes about 14 species. Its common name is red rust.