Botany MCQs
Topic Notes: Botany
MCQs and preparation resources for competitive exams, covering important concepts, past papers, and detailed explanations.
Plato
- Biography: Ancient Greek philosopher (427–347 BCE), student of Socrates and teacher of Aristotle, founder of the Academy in Athens.
- Important Ideas:
- Theory of Forms
- Philosopher-King
- Ideal State
1
Which structures are found alongside spores within the capsule of Anthoceros?
Answer:
Elaters
In the capsule of Anthoceros, pseudo-elaters are present along with the spores. These multicellular, hygroscopic structures assist in the gradual dispersal of spores by reacting to changes in humidity, ensuring efficient propagation of the species.
2
What is the name of the thick outer wall layer of a spore in Anthoceros?
Answer:
Exosporium
The spore wall in Anthoceros is differentiated into two layers: the outer, thick, and often ornamented layer called the exosporium, and the inner, thinner layer called the endosporium. The exosporium provides protection against environmental stress.
3
How many cells are produced in Anthoceros following the vertical division of the apical cell?
Answer:
Four
During the early development of the Anthoceros sporophyte or gametophyte, specific cell divisions occur. In the context of the apical cell development, vertical divisions typically result in the formation of four quadrant cells. This pattern is a fundamental aspect of the early embryological development in this hornwort genus.
4
To which taxonomic genus does the plant Anthoceros belong?
Answer:
Anthoceros
The question asks for the genus of the plant. Anthoceros is the genus name itself. Anthocerotopsida is the class, Antherocerotales is the order, and Antherocerotaceae is the family to which this genus belongs. Therefore, Anthoceros is the correct genus classification.
5
To which taxonomic division does the genus Anthoceros belong?
Answer:
Bryophyta
Anthoceros is a well-known genus of hornworts. In the plant kingdom classification, hornworts are classified under the division Bryophyta, which also includes liverworts and mosses. Anthocerotopsida is the class, while Antherocerotales is the order.
6
What is the common name for plants belonging to the class Anthocerotopsida?
Answer:
Horn worts
The class Anthocerotopsida is commonly referred to as hornworts. This name is derived from the characteristic long, horn-like sporophytes that grow from the thalloid gametophyte, distinguishing them from liverworts and mosses.
7
What is the characteristic shape of the foot in a mature Anthoceros sporangium?
Answer:
Cup like
In the genus Anthoceros, the sporophyte is differentiated into a foot, an intermediate zone (meristematic region), and a capsule. The foot is bulbous and functions as an anchor and absorptive organ, often described as cup-like or bulbous, which embeds the sporophyte into the gametophytic tissue to facilitate nutrient uptake.
8
What is the phenomenon where sporophytic cells develop directly into a gametophyte?
Answer:
Apospory
Apospory is the development of a gametophyte directly from the vegetative cells of a sporophyte without the formation of spores. This bypasses the normal alternation of generations and is observed in various bryophytes, including Anthoceros under specific conditions.
9
How many vertical divisions occur during the initial development of the Anthoceros embryo?
Answer:
A and b both
In the early embryogeny of Anthoceros, the zygote undergoes two successive vertical divisions at right angles to each other. This results in a four-celled stage (quadrant stage). Therefore, both the first and second divisions are vertical, making 'A and B both' the correct description of the initial division pattern.
10
In the development of reproductive structures, what does the inner daughter cell differentiate into?
Answer:
Antheridium
During the development of the male reproductive organ in various bryophytes and pteridophytes, the inner daughter cell resulting from the initial division of the antheridial initial undergoes further mitotic divisions to eventually form the mature antheridium, which produces the male gametes.