11. Photosynthesis generally occurs in which portions of the plant? (UPSC Prelims 1987)
[A] Leaf and other chloroplast bearing parts
[B] Steam and leaf
[C] Roots and chloroplast bearing parts
[D] Bark and leaf
Show Answer
Correct Answer: A [Leaf and other chloroplast bearing parts]
Notes:
Photosynthesis can take place in leaves, stem or green part of plant which containing chlorophyll.
12. Which of the following contained in Chlorophyll helps to absorb light? (UPSC Prelims 1989)
[A] Beryllium
[B] Calcium
[C] Magnesium
[D] Strontium
Show Answer
Correct Answer: C [Magnesium]
Notes:
As we all know, chlorophyll is one of the main pigments present in autotrophs. It contains carbon, nitogen, oxygen, hydrogen and lastly magnesium.
13. 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.
14. Oxygen transportation in a human body takes place through
I. Blood
II. Lungs
III. Tissue
The correct sequence of transportation is (UPSC Prelims 1997)
[A] I, II, III
[B] III, I, II
[C] II, I, III
[D] I, III, II
Show Answer
Correct Answer: C [II, I, III]
Notes:
The lungs serve to exchange the two gases in the blood. Oxygen enters the blood from the lungs and carbon dioxide is expelled out of the blood into the lungs. The blood serves to transport both gases. Oxygen is carried to the cells and tissues.
15. In the context of the organic evolution, the loss of limbs of snakes is explained by which of the following phenomenon? (UPSC Prelims 2002)
[A] Use and disuse of organs
[B] adaptation to living in burrows
[C] natural selection
[D] inheritance of acquired characters
Show Answer
Correct Answer: A [Use and disuse of organs]
Notes:
In organic evolution, Lamarck believed that any particular part of the body that is put into more frequent use has tendency to develop stronger and better while that part of body which is put into less or no use has tendency to gradually disappear. So, loss of limbs in snake is an example of use and disuse of organs.
16. Deficiency in which among the following leads to beriberi disease?
[A] Vitamin B1
[B] Vitamin B2
[C] Vitamin B3
[D] Vitamin B6
Show Answer
Correct Answer: A [Vitamin B1]
Notes:
Vitamin B1/Thiamine deficiency leads to a disease called beriberi. Over polishing of rice also leads to beriberi.
17. Which among the following genus is known as the ‘handy man’?
[A] Homo sapiens sapiens
[B] Homo habilis
[C] Homo sapiens neanderthelensis
[D] Homo erectus
Show Answer
Correct Answer: B [Homo habilis]
Notes:
Homo habilis– He had a face similar to his ancestors. The skull and brain size indicate that he may have been able to speak. The earliest tools made were from this era. Homo habilis is known as the ‘handy man’ because he was the first to make and use tools.
18. Which of the following statements are correct with respect to homeostasis?
1. Ecosystems are capable of maintaining their state of equilibrium.
2. They cannot regulate their own species structure and functional processes.
Select the correct option from the codes given below:
[A] Only 1
[B] Only 2
[C] Both 1 & 2
[D] Neither 1 & 2
Show Answer
Correct Answer: A [Only 1]
Notes:
Ecosystems are capable of maintaining their own state of equilibrium. They can regulate their own species structure and functional processes. This capacity of ecosystem of self regulation is referred to as homeostasis.
19. Which of the following is studied in Ethnobotany?
[A] Practical use of plants by local culture and people
[B] Relations between Plants and peoples Behvaior
[C] Comparison of different plants in a particular area
[D] Study of relations of plants, animals and animals in an area
Show Answer
Correct Answer: A [Practical use of plants by local culture and people]
Notes:
Ethnobotany is the study of the plants of an area and their practical uses through the traditional knowledge of a local culture and people.
20. Which branch of biology is known for the scientific study of organic matter in living things?
[A] Photophysical
[B] Biochemistry
[C] Biotechnology
[D] Molecular Biology
Show Answer
Correct Answer: B [Biochemistry]
Notes:
Biochemistry is the application of chemistry to the study of biological processes at the cellular and molecular level.
