Which of the following is responsible for peat formation?
Male gametophyte with least number of cells is
Select the wrong statement.
(1) Isogametes are similar in structure, function and behaviour
(2) Anisogametes differ either in structure, function and behaviour
(3) In oomycetes female gamete is smaller and motile, while male gamete is larger and non-motile
(4) Chlamydomonas exhibits both isogamy and anisogamy and Fucus shows oogamy
Isogamous condition with non-flagellated gametes is found in
Besides paddy fields, cyanobacteria are also found inside vegetative part of
Read the following statements (IV) and answer the question which follows them
I. In liverworts, mosses and ferns gametophytes are free living.
II. Gymnosperms and some ferns are heterospores.
III. Sexual reproduction in Fucus, Volvox and Albugo is oogamous.
IV. The sporophyte in liverworts is more elaborate than that in mosses.
How many of the above statements are correct?
Meiosis takes place in
Cycas and Adiantum resemble each other in having
(2) motile sperms
Which one of the following is a correct statement?
(1) Pteridophyte gametophyte has a protonemal and leafy stage
(2) In gymnosperms female gametophyte is free-living
(3) Antheridiophores and archegoniophores are present in pteridophytes
(4) Origin of seed habit can be traced in pteridophytes
Gymnosperms are also called soft wood spermatophytes because they lack
(2) phloem fibres
(3) thick-walled tracheids
(4) xylem fibres