Bryophyte short question

Q. 1. What is gemma cup ?

The most common method of the vegetative reproduction in some bryophytes take place by means of especially designed vegetative bodies, the gemma, which originated from the cup - like structure, the gemma cup, found on the dorsal surface of the thallus or at the rhizoidal portion . E.g. Marchantia sp .

Q. 2 . What are elaters ?

In some bryophytes like Marchentia , within capsule are found some exceptionally long , slender sterile cells known as elaters . They have double spiral thickening, the mature elaters lack protoplasm and function in spore dispersal .

Q. 3. What is air channel ?

In Riccia's photosynthetic zone there present green or chlorenchymatous cells which are arranged in vertical rows or column. Between the columns of green cells very narrow, deep, vertical slits are formed. These slits are called air channels.

Q. 4 . What is nurse cells ?

Pagan (1932) reported the sterility of some spore mother cell in Riccia crystalina, such sterile cells are called nurse cells .

Q. 5. What is blepharoplast ?

Riccia's androcyte possesses a big prominent nucleus and an extra nuclear granule. This granule is called blepheroplast. Two flagella arise from the anterior end of the blepheroplast .

Q. 6. What do you mean by involucre ?

In archegonia of some bryophytes like Porella develop on thallus in a group. A delicate membrane arising from the top of the ridge, covers the archegonia as in a pocket. This membranous cover is known as involucre.

Q. 7. What is amphigastria ?

In incubous arrangment of leaves on stem of some bryophytes like Porella - the small leaves of the ventral row are amphigastria.

Q. 8. What do you mean by incubous arrangement ?

Stem of some mosses like Porella bears three rows of leaf. There are two rows of dorsal leaf and one row of ventral leaf. The dorsal leaves closely overlap each other and this way they cover the stem from above. The anterior edge of the leaf cover the posterior edge of the leaf next above it, when seen from the above. Such an overlapping arrangement of the leaves is knows as incubous arrangement.

Q.9 . What is protonema ?

In bryophytes capsule spore germinates under suitable condition to give rise to main gametophyte plant directly or firstly to a juvenile, filamentous stage called protonema from which later arise the main gametophyte .

Q. 10. Why bryophytes are amphibians of plant kingdom ?

Bryophytes grow in water, land and swamps, the area where the water and land meet. They are dependent on both water and land for completion of there like cycle. So this group is called amphibian non - vascular group of plant .

Q 11. What do you mean by juvenile stage ?

In leafy gametophore the meiospore germinates and forms a slender, green branching system of filaments called protonema. This stage is called juvenile stage. The protonema further forms the gametophytE

Q. 12. Name an epiphytic bryophytes.

Dendroceros sp .

Q. 13. Name a Riccia's species where scales are absent.

Riccia crystallina .

Q. 14. Name the bryophyte which grows the highest altitude.

A moss Aongstroemia julacea has been recorded from an altitude of 19,800 ft of Himalayas .

Q. 15. Name a saprophyte bryophyte.

Buxbaumia aphylla grow upon rotted wood .

Q. 16. Name a fossil bryopsida.

Muscites bertrandi.

Q. 17. Name a monoceious and dioccious species of Riccia.

Monoccious species - Riccia crystallina.

Dioceious species - Riccia discolor.

Q. 18 . Which bryophyte has lowest chromosome number ?

Takakia sp ( 2n = 8 ) .

Q. 19. What is Madotheca ?

Porella is known as Madotheca .

Q. 20. Name the aquatic species of bryophytes.

Riccia fluitans , Ricciocarpus natans.

Q. 21. Where peristome teeth are found ?

Funaria , Polytrichum

Q. 22. Name a moss where peristome teeth are absent.

Sphagnum sp.

Q. 23. What is calyptra ?

In bryophytes the embryo remains within the venter of the female reproductive structure, i.e. archegonium. The venter wall enlarges along with the developing embryo to form the protective envelope known as calyptra .

Q. 24 . What is claterophore ?

In some bryophytes, inside the capsule wall are present elaterophore which consisted of a bundle of 20 to 100 stout, erect, fixed elaters. The lower end of the cell of elaterophore remain attach to the floor of the capsule cavity. E.g. Pellia .

Q. 25. In which bryophytes, are present parasitic algae ?

In intercellular mauilage cavity of gametophytic plant body of Anthoceros are found Cyanophycean algae Nostoc.