11. At which of the following stages the sex of the offspring is determined?
[A] The conception takes place
[B] The sperm fertilises the ovum
[C] The embryo is partially developed
[D] The end of gestation period is near
Show Answer
Correct Answer: A [The conception takes place]
Notes:
Biological sex is determined by a pair of sex chromosomes: XY in males and XX in females. Genes on the X chromosome are said to be X-linked. X-linked genes have distinctive inheritance patterns because they are present in different numbers in females (XX) and males (XY).Thus usually occurs as soon as conception takes place.
12. Which one of the following is cultivated by transplanting seedlings? (UPSC Prelims 1997)
[A] Maize
[B] Sorghum
[C] Onion
[D] Soyabean
Show Answer
Correct Answer: C [Onion]
Notes:
Onions can be grown from seeds, seedlings and bulblets. Proper nursery management and transplanting are important operations in the onion crop. About 0.05 hectare nursery bed area is enough for getting seedlings to transplant in one hectare.
13. Which is the world’s smallest bird?
[A] Red-cheeked Cordon-Bleu
[B] Costa’s Hummingbird
[C] Bee Hummingbird
[D] Goldcrest
Show Answer
Correct Answer: C [Bee Hummingbird]
Notes:
Bee Hummingbird is the smallest bird in the world. It is only 2 to 2.4 inches long and weighs 0.056 to 0.071 ounces. This bird is also known as zunzuncito or Helena Hummingbird. This bird is native to Cuba. It is endemic to the entire Cuban archipelago. It is “Nearly Threatened” bird species according to IUCN Red List of Threatened Species.
14. 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.
15. Who among the following discovered Vitamin C?
[A] Albert Szent-Györgyi
[B] Funk
[C] Evans and Bishop
[D] Henrik Dam
Show Answer
Correct Answer: A [Albert Szent-Györgyi]
Notes:
Albert Szent-György is the scientist who discovered Vitamin C. Vitamin C is a water-soluble vitamin. The chemical name is Ascorbic acid.
16. On which of the following criteria is the five-state system done?
[A] Structure of the nucleus
[B] Structure of cell wall
[C] Asexual Reproduction
[D] Mode of Nutrition
Show Answer
Correct Answer: D [Mode of Nutrition]
Notes:
The main criteria of the five kingdom classification were cell structure, body organisation, mode of nutrition and reproduction, and phylogenetic relationships.
17. Classification is based on the following criteria?
[A] Plant body
[B] Vascular system
[C] Seed formation
[D] All of the above
Show Answer
Correct Answer: D [All of the above]
Notes:
Classification is based on the following criteria: Plant body, Vascular system and Seed formation
18. What does Prothallus represent?
[A] sporophytic phase in a fern
[B] gametophytic phase in a fern
[C] sporophytic phase in a gymnosperm
[D] gametophytic phase in a gymnosperm
Show Answer
Correct Answer: B [gametophytic phase in a fern]
Notes:
Prothallus represents the gametophytic phase in a fern. The diploid sporophyte represents a major, independent, photosynthetic, and vascular plant body.
19. A compound leaf is a leaf made up of ___?
[A] two or more leaflets
[B] one leaflets
[C] No leaflets
[D] None of these
Show Answer
Correct Answer: A [two or more leaflets]
Notes:
A compound leaf is made up of two or more leaflets. In a compound leaf, the central vein of the leaf splits into individual leaves and is attached to a single stalk. For example, peas, palm leaves.
20. Which plant tissue consists of phloem and xylem?
[A] Complex Permanent Tissue
[B] Simple Permanent Tissue
[C] Parenchyma Tissue
[D] Collenchyma Tissue
Show Answer
Correct Answer: A [Complex Permanent Tissue]
Notes:
Complex Permanent Tissue tissues include phloem and xylem. Xylem helps in the transport of water and soluble components.
Phloem helps in the transportation of food particles.
