Sexual Reproduc...

Which of the following statements regarding the structure of microsporangium are correct?
(i) Microsporangium is generally surrounded by four wall layers-epidermis, endothecium, middle layers, and tapetum.
(ii) Outer three layers perform functions of protection and dehiscence of anthers.
(iii) Cells of tapetum undergo meiosis and produce microspore tetrads.

Read the given statements.
(i) Outer exine is made up of sporopollenin.
(ii) Inner intine is pecto-cellulosic in nature.
(iii) Generative cell is bigger and contains abundant food reserve.
(iv) Vegetative cell is small and floats in the cytoplasm of the generative cell.
Which of the given statements are not true regarding structure of pollen grain?

Select the mismatched pair.

A dithecous anther consists of ____(i)_______microsporangia, _____(ii)_______ in each lobe.

A typical angiospermous ovule is attached to the placenta by means of a stalk called X. Body of the ovule fuses with X in the region called Y. Identify X and Y.

Select the correct option regarding the ploidy level of different structures of an angiospermous ovule.

Which of the following options is correct?

Refer to the given characteristics of some flowers.
(i) Light and non-sticky pollen grains
(ii) Exserted stigmas and anthers
(iii) Large, often feathery stigmas
(iv) Flowers colourless, odourless and nectarless
(v) Common in grasses

Above features are the characteristics of 

Spiny or sticky pollen grains and large, attractively coloured flowers are associated with

In (i) condition, both male and female flowers are borne on the same plant; an example of such plants is (ii).

Refer to the given statements.
(i) Both wind and water pollinated flowers are not very colourful and do not produce nectar.
(ii) Entomophilous flowers are large, colourful, fragrant and rich in nectar.
(iii) Kigelia pinnata is an insect pollinated flower.
Which of the above statements is/are incorrect?

Flowering plants have developed certain outbredding devices to discourage self-pollination and encourage cross-pollination. One of these is not an examples of such outbreeding device.

______ of the pollen grain divides to form two male gametes.

Growth of pollen tube towards embryo sac is

What is the function of filiform apparatus in an angiosperm embryo sac?

The part of gynoecium that determines the compatible nature of pollen is?

The three cells found in a pollen grain when it is shed at 3-celled stage are

How many pollen mother cells should undergo meiotic division to produce 64 pollen grains? 

The inner most wall layer of anther is tapetum, the main function of tapetum is

Mature ovules are classified on the basic of funiculus. If micropyle comes to lie close to the funiculus the ovule is termed as

When micropyle, chalaza and hilum lie in a straight line, the ovule is said to be

One of the most resistant biological material present in the exine of pollen grain is

In angiosperms various stages of reductional division can best be studied in

Feathery stigma occurs in

Fragrant flowers with well developed nectaries are anadaptation for

What is the function of germ porę?

Which function of tapetum is correct?

The given diagram shows two plants of the same species. Identify the types of pollination indicated at P₁, P₂ and P₃
 .

How many meiotic divisions are required for the formation of 100 pollen grains?

How many meiotic divisions are necessary for formation of 100 functional megaspores.

During the process of fertilization the pollen tube of the pollen grain usually enters the embryo sac through

Study of pollen grains is called

Pollen kitt is generally found in

Identify the parts labelled A, B, C and D in the given figure and select the correct option.

Heterostyly as a contrivance for cross-pollination is found