Question: 100% NCERT covered from Particular Keyword.Explanations are 100% from NCERT | [Difficult level: Easy] From NCERT NEET Derived Question.
Which of the following statement(s) is/are true about
gemmae?
(i) These are specialised structures by which asexual
reproduction take place in liverworts.
(ii) They are green and multicellular.
(iii) They develop in small receptacles called gemma cups.
(iv) They detach from parent body and germinate to form
new individuals.
(a) (i) and (ii) (b) (ii) and (iii)
(c) (i), (ii) and (iii) (d) All of these
Answer:d
Liverworts
The liverworts grow usually in moist, shady habitats such as banks of
streams, marshy ground, damp soil, bark of trees and deep in the woods.
The plant body of a liverwort is thalloid, e.g., Marchantia. The thallus is
dorsiventral and closely appressed to the substrate. The leafy members
have tiny leaf-like appendages in two rows on the stem-like structures.
Asexual reproduction in liverworts takes place by fragmentation of
thalli, or by the formation of specialised structures called gemmae
(sing. gemma). Gemmae are green, multicellular, asexual buds, which
develop in small receptacles called gemma cups located on the thalli.
The gemmae become detached from the parent body and germinate to
form new individuals. During sexual reproduction, male and female sex
organs are produced either on the same or on different thalli. The
sporophyte is differentiated into a foot, seta and capsule. After meiosis,
spores are produced within the capsule. These spores germinate to form
free-living gametophytes.
