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. Which of the following bacteria is responsible for the formation of curd?
[A] Yeast
[B] Lycopodium
[C] Lacto-bacillus
[D] Fungus
Show Answer
Correct Answer: C [Lacto-bacillus]
Notes:
Lactobacillus Bacteria in Milk changes Milk to Curd. When milk is heated to a temperature of 30-40 degrees centigrade and a small amount of old curd added to it, the lactobacillus in that curd sample gets activated and multiplies. These convert the lactose into lactic acid.
14. The varieties of corn can be improved by which of the following methods?
[A] Dihybrid crosses
[B] Back cross
[C] Double cross
[D] Natural selection
Show Answer
Correct Answer: C [Double cross]
Notes:
Double-cross hybrid is the type of hybrid that is produced when two different single-cross hybrids are cross-pollinated.
15. Significantly higher level of urea in the blood is the indication of which of the following damages? (UPSC Prelims 1991)
[A] Liver damage
[B] Kidney damage
[C] Heart attack
[D] Spleen damage
Show Answer
Correct Answer: B [Kidney damage]
Notes:
Generally, a high blood urea nitrogen level means your kidneys aren’t working well. But elevated blood urea nitrogen can also be due to: Urinary tract obstruction, congestive heart failure or recent heart attack.
16. Which one of the following is a membrane that protects the developing embryo from desiccation? (UPSC Prelims 1995)
[A] Amnion
[B] Allantois
[C] Chorion
[D] Yolk sac
Show Answer
Correct Answer: A [Amnion]
Notes:
The amnion or amniotic sac protects everyone embryo from desiccation, it contains amniotic fluid which cushions the embryo from shocks.
17. Which one of the following statements is not correct? (UPSC Prelims 2003)
[A] Milk contains none of the B-vitamins
[B] Vitamin-A (retinal) deficiency leads to dry and scaly skin
[C] One of the symptoms of scurvy is pain in the joints
[D] Vitamin B1 (thiamine) deficiency can lead to heart failure
Show Answer
Correct Answer: A [Milk contains none of the B-vitamins]
Notes:
Milk contains the water soluble vitamins thiamin (vitamin B1), riboflavin (vitamin B2), niacin (vitamin B3), pantothenic acid (vitamin B5), vitamin B6 (pyridoxine), vitamin B12 (cobalamin), vitamin C, and folate. Milk is a good source of thiamin, riboflavin and vitamin B12.
18. Which of the following is a characteristic of the plant kingdom?
[A] contains cell walls and cellulose.
[B] are microscopic
[C] heterotrophic and multicellular organisms
[D] generally found in aquatic habitats
Show Answer
Correct Answer: A [contains cell walls and cellulose.]
Notes:
Plants that have a cell wall and are made of cellulose belong to the Plantae kingdom.
19. Which of the following is not an example of bryophytes?
[A] Marchantia
[B] Funaria
[C] Sphagnum
[D] Selaginella
Show Answer
Correct Answer: D [Selaginella]
Notes:
Selaginella is not an example of bryophytes. Selaginella, Equisetum, Pteris, etc.are examples of Pteridophyta.
20. A single polar flagellum is known as__?
[A] monotrichous
[B] lophotrichous
[C] amphitrichous
[D] none of these
Show Answer
Correct Answer: A [monotrichous]
Notes:
Monotrichous bacteria have a single flagellum. Lophotrichous bacteria have multiple flagella located at the same location on bacterial surfaces that work together to steer the bacteria in the same direction.
