11. Which of the following is the smallest known prokaryotic organism?
[A] Mycoplasma
[B] Bacteria
[C] Chlorella
[D] Microcystis
Show Answer
Correct Answer: A [Mycoplasma]
Notes:
Mycoplasma genitalium, a parasitic bacterium which lives in the primate bladder, waste disposal organs, genital, and respiratory tracts, is thought to be the smallest known organism capable of independent growth and reproduction.
12. Which of the following is a non-poisonous snake?
[A] Python
[B] Hognose snake
[C] Garter snake
[D] Ribbon snake
Show Answer
Correct Answer: A [Python]
Notes:
Python is a non-poisonous snake. Pythons are large muscular snakes which grow up to 35 feet and weigh as much as 300 pounds. Pythons are well known for the way they kill their preys by squeezing then to death and then swallowing them all at once.
13. Nereis, Pheretima (Earthworm) and Hirudinaria (blood sucking leech) are examples of which Phylum?
[A] Aschelminthes
[B] Coelenterata
[C] Arthropoda
[D] Annelida
Show Answer
Correct Answer: D [Annelida]
Notes:
The annelids (Annelida, from Latin anellus, “little ring”), also known as the ringed worms or segmented worms, are a large phylum, with over 22,000 extant species including ragworms, earthworms, and leeches.
14. Which of the following is the most common wheat disease in India?
[A] Green ear
[B] Smut
[C] Loose smut
[D] Rust
Show Answer
Correct Answer: D [Rust]
Notes:
Wheat leaf rust is a fungal disease that affects wheat, barley and rye stems, leaves and grains. Its infections can lead up to 20% yield loss, which is exacerbated by dying leaves, which fertilize the fungus. The pathogen of rust is Puccinia rust fungus.
15. Due to which of the following reasons the scratching eases itching? (UPSC Prelims 1993)
[A] it removes the outer dust in the skin
[B] it kills the germs
[C] it stimulates certain nerves which direct the brain to increase the production of antihistaminic chemicals
[D] it suppresses the production of enzymes which cause itching
Show Answer
Correct Answer: C [it stimulates certain nerves which direct the brain to increase the production of antihistaminic chemicals]
Notes:
Scratching helps to relieve an itch because it reduces the sensations of pain sent to the brain, a new study has found. Scientists found that skin cells in that part of the body tended to respond more to itchy substances than those in other areas.
16. 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.
17. Which tissue of plant is used to transport food to various parts?
[A] Xylem
[B] Parenchyma
[C] Sclerenchyma
[D] Phloem
Show Answer
Correct Answer: D [Phloem]
Notes:
Phloem, also called bast, are tissues in plants that conduct foods made in the leaves to all other parts of the plant. This transport process is called translocation. Phloem is composed of various specialized cells called sieve tubes, companion cells, phloem fibres, and phloem parenchyma cells.
18. Which of the following was discovered by Alexander Fleming?
[A] DNA
[B] Vaccination
[C] penicillin
[D] blood circulation
Show Answer
Correct Answer: C [penicillin]
Notes:
Alexander Fleming discovered penicillin, whose use as an antibiotic has saved millions of lives.
19. Hugo de Vries is related to which of the following theory of biology?
[A] aquatic ape theory
[B] modern anatomy
[C] Mutation Theory
[D] theory of evolution
Show Answer
Correct Answer: C [Mutation Theory]
Notes:
Hugo de Vries is a Dutch botanist and geneticist who pioneered the experimental study of biological evolution. His rediscovery of Gregor Mendel’s principles of heredity and his theory of biological mutation in 1900.
20. What are cryptogamous plants?
[A] Flowerless plant
[B] Seedless Plant
[C] Reproduce by spores
[D] All of the above
Show Answer
Correct Answer: D [All of the above]
Notes:
Cryptogamic plants include Algae, mosses, liverworts, lichens, ferns and fungi and they reproduce by spores and not producing flowers or seed.
