11. Cycas, Pinus, Ephedra are examples of which of the following?
[A] Gymnosperms
[B] Angiosperms
[C] Pteridophyta
[D] None of these
Show Answer
Correct Answer: A [Gymnosperms]
Notes:
Cycas, Pinus, Ephedra are examples of Gymnosperms. Gymnosperms have a well differentiated plant body and vascular tissue. They bear naked seeds, (the seeds are not enclosed within a fruit).
12. In bryophytes and pteridophytes, male gametes are transported through which of the following?
[A] Air
[B] Water
[C] Birds
[D] Insects
Show Answer
Correct Answer: B [Water]
Notes:
In plants, water acts as the channel through which gamete transfer takes place.
13. Where is teichoic acid commonly found?
[A] cell walls of gram positive bacteria
[B] outer membranes of gram positive bacteria
[C] cell walls of gram negative bacteria
[D] outer membranes of gram negative bacteria
Show Answer
Correct Answer: A [cell walls of gram positive bacteria]
Notes:
Teichoic acid is found within the cell wall of most Gram-positive bacteria. It appears to extend to the surface of the peptidoglycan layer, and species in the genera Staphylococcus, Streptococcus, Bacillus, Clostridium, Corynebacterium and Listeria.
14. Fungi that get their food directly from dead organic matter are called?
[A] Predators
[B] Decomposers
[C] Mutualists
[D] Parasitic fungi
Show Answer
Correct Answer: B [Decomposers]
Notes:
Fungi that get their food directly from dead organic matter are called Decomposers.
15. Which of the following is not a characteristic of Bryophyta?
[A] Motile sperms
[B] Presence of archegonium
[C] Presence of archegonium
[D] Photosynthetically independent sporophyte
Show Answer
Correct Answer: D [Photosynthetically independent sporophyte]
Notes:
Motile sperms, the Presence of archegonium, and the Presence of archegonium are characteristics of Bryophyta.
16. Which of the following tissue provides strength to the plant?
[A] Intercalary
[B] Parenchyma
[C] Sclerenchyma
[D] Collenchyma
Show Answer
Correct Answer: C [Sclerenchyma]
Notes:
Sclerenchyma provides strength to the plant. It is found in the covering of seeds and nuts, around the vascular tissues in stems and the veins of leaves.
17. Which is the innermost tissue and gives rise to the xylem and phloem?
[A] Protoderm
[B] Procambium
[C] Ground Meristem
[D] Promeristem
Show Answer
Correct Answer: B [Procambium]
Notes:
Procambium is the innermost tissue and gives rise to the xylem and phloem. It helps in transporting water and nutrients to different parts of the plant.
18. The increase in shoot and root length is called which of the following?
[A] Primary growth
[B] Secondary growth
[C] Little growth
[D] None of these
Show Answer
Correct Answer: A [Primary growth]
Notes:
The increase in the length of shoot and root is called primary growth. This shoot is the result of cell division in the apical meristem.
19. Which hormones are responsible for cell elongation in phototropism and gravitropism?
[A] Gibberellins
[B] cytokinin
[C] Auxins
[D] Abscisic Acid
Show Answer
Correct Answer: C [Auxins]
Notes:
The hormones responsible for cell elongation in phototropism and gravitropism are auxins. It also controls the differentiation of meristems into vascular tissue and promotes leaf development and arrangement.
20. Which is used as Weedicide?
[A] Indole-3-butyric acid
[B] 2,4-dichlorophenoxyacetic acid
[C] Indole-3-Acetic Acid
[D] None of these
Show Answer
Correct Answer: B [2,4-dichlorophenoxyacetic acid]
Notes:
2,4-dichlorophenoxyacetic acid is used as Weedicide. It is this auxin that is produced synthetically. It mostly affects the foliage of the plant and is widely used in the treatment of weeds.
