What is the number of microsporangia in each lobe of an angiosperm anther?
Which among the following extend longitudinally to become pollen sac?
(2) Filament of anther
Which among the following is not a feature of anther?
Which among the following is not a wall layer of microsporangium?
(4) Middle layers
All of the following statements are correct except:
(1) The proximal end of the filament is attached to the thalamus or the petal of the flower.
(2) The anther is a four-sided structure consisting of four microsporangia, two in each lobe.
(3) The number and length of stamens are variable in flowers of different species.
(4) In a longitudinal section, a typical microsporangium appears near circular in outline.
Which among the following statement is incorrect with respect to tapetum?
(1) It nourishes developing pollen grains.
(2) It has dense cytoplasm.
(3) It is the innermost wall layer of microsporangia.
(4) Cells have single nucleus only.
How tapetal cells become binucleate?
Which among the following is incorrect with respect to microsporogenesis?
(1) The cells of the sporogenous tissue undergo mitotic divisions to form microspore tetrads.
(2) Each cell of the sporogenous tissue is capable of giving rise to a microspore tetrad. Each one is a potential pollen or microspore mother cell (PMC).
(3) The microspores are arranged in a cluster of four cells called as the microspore tetrad.
(4) Inside each microsporangium several thousands of microspores or pollen grains are formed that are released with the dehiscence of anther.
The inner wall of pollen grains is made up of
(2) Cellulose and pectin
(4) Cellulose only
The pollen grains are shed at two-celled stage in
(1) 80% angiosperms
(2) 40% angiosperms
(3) 30% angiosperms
(4) 60% angiosperms