11. The highest fat content is found in the milk of which of the following animals? (UPSC Prelims 1991)
[A] Buffalo
[B] Cow
[C] Camel
[D] Reindeer
Show Answer
Correct Answer: A [Buffalo]
Notes:
Buffalo milk has the highest fat content, which is on average twice as high as that of cow milk. The fat-to-protein ratio in buffalo milk is about 2:1.
12. Which one of the following is useful for biological control of pests? (UPSC Prelims 1991)
[A] Honey bees and locusts
[B] Scorpions and spiders
[C] Wasps and birds
[D] Parrots and kites
Show Answer
Correct Answer: B [Scorpions and spiders]
Notes:
Spiders, mites, scorpions, and several related groups are not insects, but belong to the arthropod class Arachnida. About 15 families of spiders are frequently encountered in crops, where they provide benefit as natural control agents.
13. Which among the following is the name given to the ductless and secretory glands in the human body? (UPSC Prelims 1997)
[A] Endocrine glands
[B] Exocrine glands
[C] Salivary glands
[D] None of the above
Show Answer
Correct Answer: A [Endocrine glands]
Notes:
Ductless glands which are also known as internally secreting glands or endocrine glands secrete their products or hormones directly into the blood stream in response to instructions from the brain.
14. Match List I and List II and select the correct answer by using the codes given below the lists:
|
List I
|
List II
|
|
I. Malaria
|
(A) Bone marrow
|
|
II. Filaria
|
(B) Brain
|
|
III. Encephalitis
|
(C) Muscle
|
|
IV. Leukaemia
|
(D) Lymph node
|
|
|
(E) Blood cells
|
Codes: (UPSC Prelims 1997)
[A] I-E, II-C, III-B, IV-A
[B] I-E, II-D, III-B, IV-A
[C] I-D, II-C, III-E, IV-A
[D] I-E, II-D, III-A, IV-B
Show Answer
Correct Answer: B [I-E, II-D, III-B, IV-A]
Notes:
• Invasion by the malaria parasite, Plasmodium falciparum, brings about extensive changes in the host red cells. Numerous proteins secreted by the internalized parasite and interacting with red cell membrane proteins are responsible for the changes occurring to the host cell.
• Lymphatic filariasis is caused by the worms Wuchereria bancrofti, Brugia malayi, and Brugia timori. These worms occupy the lymphatic system, including the lymph nodes; in chronic cases these worms lead to the syndrome of elephantiasis. These worms occupy the subcutaneous layer of the skin, in the fat layer.
• Encephalitis is an acute inflammation of the brain usually resulting from either a viral infection or due to the body’s own immune system mistakenly attacking brain tissue.
• Leukaemia is a cancer that starts in blood-forming tissue, usually the bone marrow. It leads to the over-production of abnormal white blood cells, the part of the immune system which defends the body against infection.
15. Who was awarded the Nobel Prize in Medicine for the discovery of cell signalers?
[A] Alfred G. Gilman
[B] Martin Rodbell
[C] Both 1 & 2
[D] None of these
Show Answer
Correct Answer: C [Both 1 & 2]
Notes:
Alfred G. Gilman and Martin Rodbell were awarded the Nobel Prize in Medicine for the discovery of cell signalers called G-proteins.
16. 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.
17. The sporophytic generation is represented only by the zygote__?
[A] Funaria
[B] Chlamydomonas
[C] Pinus
[D] Pinus
Show Answer
Correct Answer: B [Chlamydomonas]
Notes:
Important Features of Chlamydomonas: The plant body is unicellular, pear-shaped, and biflagellate, Each cell typically contains a cup-shaped chloroplast, an eye sac, and two contractile vacuoles, Pamela-stage appearance, Asexual reproduction occurs through biflagellate zoospore formation.
18. Which of the following is wrong for bryophytes?
[A] Vascular tissue lacking clear
[B] Independent sporophyte absent clear
[C] Gametophyte reduced and dependent done
[D] Asexual reproduction by zoospores absent
Show Answer
Correct Answer: C [Gametophyte reduced and dependent done]
Notes:
The main plant of Bryophyta is the gametophyte. The gametophytic stage is independent.
19. In the absence of which of the following will photosynthesis not occur in leaves?
[A] Chlorophyll
[B] Guard cells
[C] Space between cells
[D] Vacuole
Show Answer
Correct Answer: A [Chlorophyll]
Notes:
In the absence of chlorophyll, photosynthesis does not occur in leaves. The chlorophyll in leaves helps capture the energy of sunlight. Chlorophyll is a green pigment found in plants.
20. What is the actual role of abscisic acid?
[A] to close the stomata
[B] the tiny openings in leaves that allow substances to enter and leave
[C] to maintain dormancy
[D] All of the above
Show Answer
Correct Answer: D [All of the above]
Notes:
The actual role of abscisic acid is to close stomata, the small openings in leaves that allow substances to enter and leave, and maintain dormancy.