Question
Question: A plant shows the thallus level of the organization. It shows rhizoids and is haploid. It needs wa...
A plant shows the thallus level of the organization. It shows rhizoids and is haploid. It
needs water to complete its life cycle because the male gametes are motile. It may belong to
A. Pteridophytes
B. Gymnosperms
C. Monocots
D. Bryophytes
Solution
The plants or groups which have these features have very simple organization and are haploid. Water is required for sexual reproduction by these plants and commonly known as amphibians of the plant kingdom.
Complete answer:
In option -A- Pteridophytes, these are vascular plants and their body is differentiated into root, stem, and leaves. They reproduce by spores. There is no thallus body, presence of roots.
In option -B- Gymnosperms, these are known as naked seed plants. Their body is well-differentiated into roots, stem, and leaves, and therefore no thallus appearance. Their gametes need no water instead they grow via seeds.
In option -C- Monocots, these come under angiosperms and have seed covered with flowers i.e. seeds are not naked and have a single cotyledon. These plants also have good differentiation. Also, they do not need water for their gametes. They have roots and no rhizoids.
In option -D- Bryophytes, the general features of this group are mainly these plants are haploid i.e. the main plant body is haploid. In these plants, true differentiation is absent i.e. they have a thallus-like body. They lack roots, stem, and leaves instead they have rhizoids that attach them to the ground. Bryophytes are called amphibians of the plant kingdom as their sexual reproduction is dependent on water i.e. their male gametes are ciliated/flagellated and need water to reach the female gamete for fertilization.
So, the correct answer to this question is the option” D” Bryophytes
Note: The plant kingdom is divided into Algae, Bryophytes, Pteridophytes, Gymnosperms, Angiosperms. These all are multicellular, eukaryotic, and are divided into these groups on their features morphological and their body functions.