Q81. A plant that produces gametes is called a:
[A] Sporophyte
[B] Gametophyte
[C] Thallus
[D] Prothallus
Show Answer
Correct Answer: [B] Gametophyte
Explanation: A gametophyte is the haploid generation in the life cycle of plants that produces gametes (sperm and egg) through mitosis. The fusion of these gametes forms a diploid zygote, which develops into the sporophyte.
Q82. The first cell of the sporophytic generation is the:
[A] Spore
[B] Gamete
[C] Zygote
[D] Embryo
Show Answer
Correct Answer: [C] Zygote
Explanation: The sporophytic generation begins with the formation of a diploid zygote, which is the result of the fusion of male and female gametes. The zygote then undergoes mitosis to develop into the multicellular sporophyte.
Q83. The first cell of the gametophytic generation is the:
[A] Zygote
[B] Embryo
[C] Spore
[D] Gamete
Show Answer
Correct Answer: [C] Spore
Explanation: The gametophytic generation begins with a haploid spore, which is produced by the sporophyte through meiosis. The spore undergoes mitosis to develop into the multicellular haploid gametophyte.
Q84. Reduction division during the plant life cycle occurs in the:
[A] Gametes
[B] Zygote
[C] Spores
[D] Sporangia
Show Answer
Correct Answer: [D] Sporangia
Explanation: Reduction division (meiosis) occurs in the sporangia of the sporophyte to produce haploid spores. This marks the transition from the diploid sporophytic generation to the haploid gametophytic generation.
Q85. The multicellular sex organs in bryophytes are called:
[A] Gametes
[B] Spores
[C] Gametangia
[D] Sporangia
Show Answer
Correct Answer: [C] Gametangia
Explanation: Bryophytes have multicellular sex organs. The male sex organ is called the antheridium, which produces sperm, and the female sex organ is called the archegonium, which contains a single egg. These multicellular structures are collectively known as gametangia.
Q86. The multicellular spore-producing organs are called:
[A] Gametangia
[B] Sporangia
[C] Gametes
[D] Spores
Show Answer
Correct Answer: [B] Sporangia
Explanation: Sporangia are multicellular structures in plants where meiosis occurs to produce haploid spores. These spores are then released and develop into the gametophyte generation.
Q87. In angiosperms, the male gametophyte is highly reduced and confined to the:
[A] Ovule
[B] Embryo sac
[C] Pollen grain
[D] Endosperm
Show Answer
Correct Answer: [C] Pollen grain
Explanation: In angiosperms, the male gametophyte is highly reduced and is represented by the pollen grain. The pollen grain contains the vegetative cell and the generative cell, which divides to form two male gametes.
Q88. In angiosperms, the female gametophyte is called the:
[A] Pollen grain
[B] Embryo sac
[C] Ovule
[D] Endosperm
Show Answer
Correct Answer: [B] Embryo sac
Explanation: In angiosperms, the female gametophyte is called the embryo sac. It is located within the ovule and typically contains eight nuclei in seven cells, including the egg cell, central cell, and synergids.
Q89. The transfer of male gametes to the female gametes in bryophytes and pteridophytes is facilitated by:
[A] Wind
[B] Water
[C] Insects
[D] Animals
Show Answer
Correct Answer: [B] Water
Explanation: In bryophytes and pteridophytes, the male gametes (sperm) are flagellated and require water to swim to the female gametes (egg) for fertilization. This is why these plants are often found in moist environments.
Q90. Which of the following is a gymnosperm that resembles angiosperms in having vessels in its xylem?
[A] Pinus
[B] Cycas
[C] Gnetum
[D] Sequoia
Show Answer
Correct Answer: [C] Gnetum
Explanation: Most gymnosperms lack vessels in their xylem, but Gnetum is an exception. It possesses vessels, which are more efficient in water conduction, a feature commonly found in angiosperms.