11. Which of the following is the reason behind bleeding through nose in high mountain regions? (UPSC Prelims 1979).
[A] The pressure of the blood capillaries is higher than the outside pressure
[B] The pressure at high altitudes is greater than that in the plains
[C] The blood pressure increases at high altitudes
[D] The blood pressure decreases at high altitudes
Show Answer
Correct Answer: A [The pressure of the blood capillaries is higher than the outside pressure]
Notes:
As altitude increases, the availability of oxygen decreases, making the air thinner and drier. Dry climates can cause drying and cracking inside the nose, which can lead to a nosebleed. The climate inside nose gets drier. This makes the blood vessels exposed inside your nose more likely to burst there than at lower altitudes.
12. Which one of the following is not an essential micronutrient for plants? (UPSC Prelims 1996)
[A] Boron
[B] Zinc
[C] Sodium
[D] Copper
Show Answer
Correct Answer: C [Sodium]
Notes:
There are 13 essential nutrients required by plants for its healthy and proper growth. Now these nutrients are divided into two categories:
Macronutrients (nitrogen, phosphorus, potassium, calcium, magnesium and sulphur)
Micronutrients (iron, copper, manganese, zinc, boron, molybdenum and chlorine)
Additional mineral nutrient elements which are beneficial but not necessary are sodium, cobalt, vanadium, nickel, solenium, aluminium and silicon. Thus boron, zinc and copper falls into category of essential micronutrients while sodium does not.
13. Which of the following concepts was explained by Stephen Hales?
[A] new species are formed from the sudden and unexpected emergence of alterations in their defining traits.
[B] plant function and behaviour
[C] principles of genetics and inheritance to the improvement of the human race
[D] None of these
Show Answer
Correct Answer: B [plant function and behaviour]
Notes:
Plant physiology is the study of plant function and behaviour. This concepts was explained by Stephen Hales.
14. What is the process in which material is ingested by the cells through the plasma membrane?
[A] Egestion
[B] Diffusion
[C] Osmosis
[D] Endocytosis
Show Answer
Correct Answer: D [Endocytosis]
Notes:
Endocytosis is the process in which the ingestion of material by the cells is carried out through the plasma membrane.
15. Which of the following compounds is not found in protein?
[A] Carbon
[B] Hydrogen
[C] Sulfur
[D] Helium
Show Answer
Correct Answer: D [Helium]
Notes:
Protein is made up of amino acids and is the main bodybuilding biomolecule of our body. 75% of the body is made up of protein, The main compounds of protein are carbon, hydrogen, oxygen, nitrogen, and sulfur.
16. Which of the following plant group requires both land and water to complete its life cycle?
[A] Tracheophyta
[B] Pteridophyta
[C] Thallophyta
[D] Bryophyta
Show Answer
Correct Answer: D [Bryophyta]
Notes:
Bryophyta plant group requires both land and water to complete its life cycle. Bryophytes are an informal division consisting of 3 groups of non-vascular plants, namely mosses, liverworts and hornworts.
17. Chemotaxis is a phenomenon of__?
[A] swimming away of bacteria
[B] swimming towards a bacteria
[C] swimming away or towards of bacteria in presence of chemical compound
[D] All of the above
Show Answer
Correct Answer: C [swimming away or towards of bacteria in presence of chemical compound]
Notes:
Chemotaxis is a phenomenon of swimming away or towards of bacteria in presence of chemical compound.
18. The redwood tree is__?
[A] Cedrus
[B] Pinus
[C] Dalbergia
[D] Sequoia
Show Answer
Correct Answer: D [Sequoia]
Notes:
The redwood tree is Sequoia. Redwoods are coniferous trees (gymnosperms) and are known as the tallest trees in the world. They can live for thousands of years and prefer to live in mountainous areas.
19. Which of the following performs an important function of flowers?
[A] They help in the process of reproduction
[B] They produce diaspores without fertilization
[C] The gametophytes develop inside the flower
[D] All of the above
Show Answer
Correct Answer: D [All of the above]
Notes:
Flowers perform the following important functions: they help in the process of reproduction, they produce diaspores without fertilization, gametophytes develop inside the flower, flowers attract insects and birds which then transfer pollen from one’s anther act as a medium to Flowers till the stigma of another flower, the ovary of the flower develops into a fruit that contains the seed.
20. Name the plant tissue which helps in the transport of food.
[A] Xylem
[B] Aerenchyma
[C] Phloem
[D] Chlorenchyma
Show Answer
Correct Answer: C [Phloem]
Notes:
Phloem tissue helps in the transport of food throughout the plant. The diverse elements of phloem include phloem fibers, sieve tubes, phloem parenchyma, and companion cells.
