Given below are two statements: [2023]
One is labeled as Assertion (A) and the other is labeled as Reason (R).
Assertion (A): The first state of gametophyte in the life cycle of moss is protonema stage.
Reason (R): Protonema develops directly from spores produced in capsule.
In the light of the above statements, choose the most appropriate answer from the options given below:
(A) is correct but (R) is not correct.
(A) is not correct but (R) is correct.
Both (A) and (R) are correct and (R) is the correct explanation of (A).
Both (A) and (R) are correct but (R) is not the correct explanation of (A).
(3)
The predominant stage of the life cycle of a moss is the gametophyte, which consists of two stages – protonema stage and leafy stage. The first stage is the protonema stage, which develops directly from a spore. The spores are formed after meiosis in the capsule.
Gemmae are present in [2021]
some liverworts
mosses
pteridophytes
some gymnosperms
(1)
In some liverworts like Marchantia, special structures called gemmae are present for asexual reproduction.
Which one is wrongly matched? [2018]
Uniflagellate gametes – Polysiphonia
Biflagellate zoospores – Brown algae
Gemma cups – Marchantia
Unicellular organism – Chlorella
(1)
A non-motile male gamete or spermatium is the characteristic feature of Polysiphonia.
Which of the following is responsible for peat formation? [2014]
Marchantia
Riccia
Funaria
Sphagnum
(4)
Among the bryophytes, Sphagnum accounts by far the most important place economically. It is popularly called bog moss or peat moss. It is perennial, and its growth continues year after year. Older portions undergo death but do not decompose due to the secretion of acid that accounts for the antibacterial and antifungal actions. The increasing mass of dead remains accumulates year after year and forms a compact dark-colored mass rich in carbon, which is called peat. Peat is used as fuel. Paraffin, acetic acid, peat tar, and ammonia are formed as by-products of peat obtained for industrial uses.
