11. Which of the following plants is biennial? (UPSC Prelims 1989)
[A] Banana
[B] Pineapple
[C] Jack fruit
[D] Carrot
Show Answer
Correct Answer: D [Carrot]
Notes:
The Carrot plant is biennial and develops, in its second year.
12. Natural rubber is a plant product which is chemically known by which of the following names? (UPSC Prelims 1992)
[A] Mucilage
[B] Gum
[C] Latex
[D] Resin
Show Answer
Correct Answer: C [Latex]
Notes:
The word latex means only natural rubber. Natural rubber is made from the white sap of some trees such as the Hevea brasiliensis (Euphorbiaceae). Other elastomers, called synthetic rubbers, are made by chemical processes.
13. 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.
14. Which gas is released during the process of photosynthesis in plants?
[A] Carbon dioxide
[B] Methane
[C] Oxygen
[D] Nitrogen
Show Answer
Correct Answer: C [Oxygen]
Notes:
Inputs of photosynthesis are carbon dioxide and water and outputs are glucose and oxygen. Photosynthesis occurs in the presence of sunlight.
15. Which gland acts as thermostat of human body?
[A] Pancreas
[B] Pituitary
[C] Thyroid
[D] Hypothalamus
Show Answer
Correct Answer: D [Hypothalamus]
Notes:
Hypothalamus acts as the thermostat of human body as it regulates the body temperature as the same way a thermostat controls the room temperature. It is located in the skull of the human body.
16. 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.
17. Which modern concept was pioneered by Rudolf Virchow?
[A] pathological processes
[B] process of fermentation
[C] isotopes as tracers to study chemical and biological processes
[D] None of these
Show Answer
Correct Answer: A [pathological processes]
Notes:
Rudolf Virchow was a German pathologist and politician who pioneered the modern concept of disease processes by his application of cell theory to explain the effects of disease in body organs and tissues.
18. Who among the following is considered to be the father of DNA?
[A] James Watson
[B] Hargobind Khurana
[C] Alec Jeffereys
[D] Leslie Orgel
Show Answer
Correct Answer: A [James Watson]
Notes:
James Dewey Watson is an American molecular biologist, geneticist, and zoologist. In 1953, he co-authored with Francis Crick the academic paper proposing the double helix structure of the DNA molecule.
19. Which of the following is true for chromatin?
[A] These are highly condensed DNA
[B] It is found in the nucleus
[C] It contains a single dsDNA
[D] All of the above
Show Answer
Correct Answer: D [All of the above]
Notes:
Chromatin is a complex of DNA and proteins that make up chromosomes within the nucleus of eukaryotic cells.
20. 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.
