11. Which among the following does not have a cell wall?
[A] Mycoplasma
[B] Paramecium
[C] Euglena
[D] Gonyaulax
Show Answer
Correct Answer: A [Mycoplasma]
Notes:
Mycoplasma are a mollicute genus of bacteria that lack a cell wall around their cell membranes. Mycoplasma species are the smallest bacterial cells yet discovered, can survive without oxygen, and come in various shapes.
12. Which among the following are female sex harmones?
[A] Estrogen
[B] Progesterone
[C] Testosterone
[D] Both a and b
Show Answer
Correct Answer: D [Both a and b]
Notes:
Estrogen and progesterone are the female sex harmones. Estrogen is responsible for the development of secondary sexual characteristics. Progesterone supports during pregnancy and controls the menstrual cycles in women.
13. Which branch of biology is known for the study of fruits?
[A] Pomology
[B] Agronomy
[C] Floriculture
[D] None of these
Show Answer
Correct Answer: A [Pomology]
Notes:
Pomology is a branch of botany that studies fruit and its cultivation.
14. Who was the father of DNA Fingerprinting?
[A] James Watson
[B] Hargobind Khurana
[C] Alec Jeffereys
[D] Nirenberg
Show Answer
Correct Answer: C [Alec Jeffereys]
Notes:
In 1984, Alec Jeffreys developed the technique of DNA fingerprinting. These techniques have revolutionised the way that the police solve crimes.
15. The most abundant biomolecule on earth is__?
[A] Minerals
[B] Salts
[C] Carbohydrates
[D] Vitamins
Show Answer
Correct Answer: C [Carbohydrates]
Notes:
Carbohydrate is a biomolecule that is found in the most abundance on earth. Carbohydrates are mostly produced by green plant cells, algae and some bacteria.
16. When is reverse transcriptase a useful enzyme?
[A] an RNA virus converts its RNA to DNA
[B] there are no host cells present
[C] nutrients are scarce
[D] spikes are forming in the new virus
Show Answer
Correct Answer: A [an RNA virus converts its RNA to DNA]
Notes:
Reverse transcriptase is a useful enzyme to have when an RNA virus converts its RNA to DNA. Reverse transcriptase converts RNA sequences into cDNA sequences that are capable of being inserted into different regions of the genome.
17. Which bacteria are used in production of biogas/gobar gas plants?
[A] Methanogens
[B] Ethanogens
[C] Propanogens
[D] N-butane
Show Answer
Correct Answer: A [Methanogens]
Notes:
Methanogens belong to the Euryarchaeota of the Archaebacteria. They convert inorganic organic compounds into methane and carbon dioxide.
18. Which of the following happens in Gram-positive cells?
[A] second outer membrane that helps to retain the crystal violet stain
[B] multiple layer of peptidoglycan that helps to retain the crystal violet stain
[C] thick capsule that traps the crystal violet stain
[D] periplasmic space that traps the crystal violet
Show Answer
Correct Answer: B [multiple layer of peptidoglycan that helps to retain the crystal violet stain]
Notes:
Multiple layer of peptidoglycan that helps to retain the crystal violet stain is happens in Gram-positive cells. Gram-positive organisms have a thicker peptidoglycan cell wall than Gram-negative bacteria.
19. What is Saprophytic nutrition?
[A] obtaining food and utilizing it to grow, stay healthy and repair any damaged body part
[B] digest the insects by secreting digestive juices and absorb the nutrients from them
[C] derive nutrition from dead and decaying plants and animals
[D] None of these
Show Answer
Correct Answer: C [derive nutrition from dead and decaying plants and animals]
Notes:
Saprophytic plants obtain nutrition from dead and decaying plants and animals, and they dissolve the dead and decaying matter and absorb its nutrients by secreting digestive juices.
20. Which of the following is located inside the embryo sac?
[A] Stigma
[B] Ovule
[C] Micropyle
[D] Style
Show Answer
Correct Answer: B [Ovule]
Notes:
The ovule is located inside the embryo sac. The embryo sac develops within the ovule surrounded by the nucellus, which in turn is surrounded by integuments.
