Prepare for NEET with Botany-specific practice questions. Covering all major Botany chapters, this is perfect for your NEET Biology needs.
In gymnosperms, the megaspore mother cell undergoes:
Mitosis to form two megaspores, both of which are functional.
Meiosis to form four megaspores, all of which are functional.
Meiosis to form four megaspores, of which one is functional.
Mitosis to form four megaspores, of which three are functional.
In heterosporous pteridophytes, the development of the male gametophyte predominantly occurs:
Within the megaspore wall
Outside the spore wall
Partially inside and outside the spore wall
Within the microspore wall
Which of these characteristics is NOT associated with the evolution of heterospory in pteridophytes?
Reduction in the number of megaspores
Increased protection of the female gametophyte
Development of endosporic gametophytes
Increased dependence on water for fertilization
Which of the following pteridophytes is heterosporous?
Dryopteris
Pteris
Selaginella
Adiantum
In a plant species with a diploid number of 12, a mutation causes complete failure of cytokinesis following telophase II of meiosis. What would be the ploidy of the resulting megaspore?
Haploid (n=6)
Diploid (2n=12)
Triploid (3n=18)
Tetraploid (4n=24)
A plant species exhibits diplospory. Which of the following statements accurately describes the origin of the embryo sac in this species?
The embryo sac develops directly from the megaspore mother cell without meiosis.
The embryo sac develops from a haploid megaspore after meiosis.
The embryo sac develops from a nucellar cell.
The embryo sac develops from an integumentary cell.
In gymnosperms one of the megaspores develops into multicellular structure called multicellular …… that bears two or more archegonia
Male gametophyte
Female gamete
Female gametophyte
Male gamete
Consider the following statement regarding heterospory
I. Genera like Selaginella and Salvinia which produce two kinds of spores, macro (large) and micro (small) spores, are known as heterosporous
II. The megaspores and microspores germinate and give rise to female and male gametophyte respectively
III. The female gametophytes in these plants are retained on the parent sporophytes for variable periods
IV. The development of the zygotes into young embryos takes place within the female gametophytes
V. This event is a precursor to the seed habit considered an important step in evolution
I, II and III
II, IV and V
III, IV and V
I, II, III, IV and V
Functional megaspore develops into …A… also called …B…
A and B in the above sentence is
A-Female gametophyte; B-Embryo sac
A-Embryo sac; B-Female gametophyte
A-Endosperm; B-Nucellus
A-Microsporangium; B-Megasporangium
Megasporogenesis is
The process of formation of megaspores from the megaspore mother cell.
The development of the pollen grain in the anther.
The fusion of male and female gametes in plants.
The development of the fruit after fertilization.
