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Assertion :- Inner mostlayerofmicrospora...

Assertion :- Inner mostlayerofmicrosporangium or pollen sac, tapetum is of physiological significance.
Reason :- All kindof nutritionof developingpollen grains go through tapetum.

A

A

B

B

C

C

D

D

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Read the following text and answer the following questions on the basis of the same: A typical anther is bilobed. It is a tetragonal structure consisting of four microsporangia. These microsporangia form pollen sac which on maturity gets filled with a pollen grains. Pollen grains represent the male gametophytes, their cell wall is very hard. Pollen grains of many species cause severe allergies which cause various diseases in human beings. Assertion (A) : The innermost layer of microsporangium is called tapetum. Reason (R) : Tapetum nourishes the develop into pollen grains.

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Consider the following statements and choose the correct option. I. Primary endosperm nucleus is triploid. II. In grass and water lily plant, pollination occurs through water. III. Tapetum nourishes the developing pollen grains. IV. Hilum represents the junction between ovule and funiculus.

Read the following statements and find out the incoorect statement. a. the number and length of stamens is variable in flowers of same species. b. A typical angiosperm anther is bilobed with each lobe having two theca. c. Often a longitudinal groove runs lengthwise separating the theca. d. The anther consists of four microsporangia located at the corners one in each lobe. e. the microsporangia develop further and become pollen sacs. They extend longitudinally all through the length of an anther and are packed with pollen grains.

Study the following lists {:("List-I",,"List-II"),("A. Endothecium",,"I. present between the pollen sacs"),("B.Tapetum",,"II. Fibrous thickenings"),("C.Stomium",,"III. Outer layer of microsporangium"),("D. Sporogenous tissue ",,"IV. Nourishes the pollen grains"),("",,"V. Centre of microsporangium"):}