Prepare for NEET Biology Plant Kingdom with MCQs & PYQs on NEET.GUIDE. Access free practice, previous year questions, and expert solutions to understand plant diversity and groups.
The haplontic life cycle is dominant in which algal group, where the zygote is the only diploid stage?
Fucus
Ectocarpus
Polysiphonia
Volvox
Which algal division is characterized by the presence of a 'peculiar' type of nuclear division and the absence of flagellated stages in its life cycle?
Chlorophyta
Phaeophyta
Rhodophyta
Xanthophyta
In the life cycle of Polysiphonia, a complex Rhodophycean alga, what unique characteristic distinguishes it from most other algal groups?
Presence of a dominant sporophyte generation
Lack of motile gametes
Three multicellular phases: carposporophyte, tetrasporophyte, and gametophyte
Production of non-motile spores
Which of the following features is NOT characteristic of floridean starch, the storage carbohydrate found in Rhodophycea?
Branched structure similar to amylopectin
Stored in the cytoplasm
Amylose with ฮฑ-1,4 linkages
Absence of plastids within the pyrenoids
Which specific characteristic of Rhodophycean cell walls contributes significantly to their flexibility and allows them to withstand strong water currents?
High cellulose content
Presence of lignin
Sulfated galactans like agar and carrageenan
Deposition of silica
Which specific characteristic of Selaginella leads to its classification as a heterosporous pteridophyte?
Presence of rhizophores
Production of megaspores and microspores within the same strobilus
Homosporous nature with a single type of spore
Lack of a distinct strobilus
Which feature distinguishes the prothallus of Psilotum from that of most other pteridophytes?
Photosynthetic and above ground
Subterranean and saprophytic nature
Presence of distinct antheridia and archegonia on the same prothallus
Heart-shaped and free-living
In which pteridophyte does the stem have a distinct 'siphonostele' with a central pith surrounded by vascular tissue?
Psilotum
Selaginella
Equisetum
Lycopodium
Which of the following statements regarding the development of the male gametophyte in Pinus is INCORRECT?
Microspore is the first cell of the male gametophyte.
The prothallial cell eventually degenerates.
The generative cell directly develops into the sterile cell and two male gametes.
A tube cell and a generative cell are formed after the first mitotic division of the microspore.
In gymnosperms, the ovule is considered naked because:
It lacks an integument.
It is not enclosed within an ovary.
It is exposed before fertilization.
It lacks a megasporangium.
