21. Consider the following statements regarding Typhoid:
- Typhoid is caused by the bacterium Salmonella typhi.
- BCG immunization is used to prevent Typhoid.
Which of the above statements is/are correct?
[A] Only 1
[B] Only 2
[C] Neither 1 nor 2
[D] Both 1 and 2
Show Answer
Correct Answer: C [Neither 1 nor 2]
Notes:
The first statement is correct as Typhoid is caused by Salmonella typhi. The second statement is incorrect since BCG vaccine prevents Tuberculosis, not Typhoid. Typhoid prevention uses Typhoid-specific vaccines such as Vi polysaccharide and conjugate vaccines, not BCG. Thus, neither statement 1 nor 2 is entirely correct.
22. Consider the following plants:
- Bougainvillea
- Carnations
- Cocoa
- Grapes
Which of the above plants are propagated by stem cuttings?
[A] Only 1 and 2
[B] 2, 3 and 4
[C] 1, 2, 3 and 4
[D] 1, 3 and 4
Show Answer
Correct Answer: C [1, 2, 3 and 4]
Notes:
Stem cutting is a common method of vegetative plant propagation. Bougainvillea, carnations, cocoa, and grapes all can be propagated by stem cuttings due to their capacity to develop roots from stems, enabling clonal reproduction. This technique is widely used in horticulture for mass multiplication of these plants.
23. Which of the following statements regarding ponds is/are correct?
- A pond is an area filled with water, either natural or artificial, that is smaller than a lake.
- Ponds created by animals are called beaver ponds.
- Vernal ponds are ponds flowing throughout the year.
Select the correct answer from the codes given below:
[A] Only 1 & 3
[B] Only 1 & 2
[C] 1, 2 & 3
[D] None of the above
Show Answer
Correct Answer: B [Only 1 & 2]
Notes:
A pond is a small body of standing water, smaller than a lake, formed naturally or artificially. Ponds created by animals, like beavers, are called beaver ponds. Vernal ponds do not flow throughout the year; they are temporary and dry up seasonally.
24. Which among the following fertilizers is the least traded fertilizer in the international market?
- Nitrogen
- Phosphate
- Potash
Select the correct code from the options given below:
[A] Only 1
[B] Only 2
[C] Only 3
[D] 1, 2 & 3
Show Answer
Correct Answer: A [Only 1]
Notes:
Though a bulky and rather low priced commodity, chemical fertilisers enter international trade in large amount. Nitrogen
is the least traded among the three nutrients with less than one-fifth of the total production entering international trade.
25. Which of the following statements regarding Gymnosperms are correct?
- They are the naked-seeded plants.
- There is no ovary, style, or stigma present.
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: C [Both 1 & 2]
Notes:
Gymnosperms are called naked-seeded plants as their seeds are not enclosed within an ovary. They lack floral structures such as ovary, style, and stigma. Examples include Cycas, Pinus, and Gnetum. These features distinguish them from angiosperms, which possess enclosed seeds and true flowers.
26. Which of the following pairs of autoimmune diseases and affected organs are correctly matched?
- Hashimoto disease – Thyroid
- Addison disease – Small Intestine
- Sjogren syndrome – Tear Glands
- Celiac disease – Adrenal Glands
Select the correct answer using the codes given below:
[A] Only 1 & 4
[B] Only 1 & 2
[C] Only 3 & 4
[D] Only 1 & 3
Show Answer
Correct Answer: D [Only 1 & 3]
Notes:
Hashimoto disease is an autoimmune disorder affecting the thyroid gland. Addison disease impacts the adrenal glands, not the small intestine. Sjogren syndrome targets tear and salivary glands, causing dryness. Celiac disease damages the lining of the small intestine, not the adrenal glands. Thus, only pairs 1 and 3 are correctly matched.
27. Consider the following statements:
- Almost all birds and mammals are capable of thermoregulation and osmoregulation.
- Nearly all plants cannot maintain a constant internal environment.
- Aquatic animals and mostly all plants are conformers.
Which of the above statements is / are correct?
[A] Only 1 and 2
[B] Only 2 and 3
[C] All of the above
[D] Only 1 and 3
Show Answer
Correct Answer: D [Only 1 and 3]
Notes:
Birds and mammals are capable of physiological regulation for temperature and osmosis, while a vast majority of animals and nearly all plants cannot maintain internal constancy, making them conformers. Statement 1 and 3 are therefore correct. Statement 2 is incorrect because although most, but not nearly all, plants lack homeostasis mechanisms for maintaining a constant internal environment.
28. Consider the following:
- Pacific salmon fish
- Bamboo
- Birds
- Mammals
Which of the above species breed only once in their lifetime?
[A] Only 1, 2, and 4
[B] Only 2, 3, and 4
[C] Only 1 and 2
[D] All of the above
Show Answer
Correct Answer: C [Only 1 and 2]
Notes:
Populations evolve to maximise their reproductive fitness, also called Darwinian fitness in the habitat in which they live. Some organisms breed only once in their lifetime (Pacific salmon fish, bamboo) while others breed many times during their lifetime (most birds and mammals).
29. Consider the following statements:
- The food relationship between organisms at different trophic levels is triangular shaped.
- The base of each energy pyramid represents the tertiary or top level consumer.
Which of the above is / are correct?
[A] Only 1
[B] Only 2
[C] Both 1 and 2
[D] None of the above
Show Answer
Correct Answer: B [Only 2]
Notes:
The food or energy relationship between organisms at different trophic levels is pyramid shaped i.e. broad at its base and narrows towards the apex. This, relationship is expressed in terms of number, biomass or energy. The base of each pyramid represents the producers or the first trophic level while the apex represents tertiary or top level consumer.
30. Which of the following pairs are correctly matched?
- Milk – Minerals
- Carrot – Vitamins
- Fish – Carbohydrates
Select the correct answer from the codes given below:
[A] Only 1 and 2
[B] Only 2 and 3
[C] Only 1 and 3
[D] 1, 2 and 3
Show Answer
Correct Answer: A [Only 1 and 2]
Notes:
Milk is a good source of minerals like calcium and phosphorus. Carrots are rich in vitamins, especially vitamin A. Fish is primarily a source of protein and fats, not carbohydrates. Therefore, only statements 1 and 2 are correctly matched; statement 3 is incorrect.
