What are chasmogamous flowers? Can cross-pollination occur in cleistogamous flowers? Give reasons for your answer.  

What is meant by monosporic development of female gametophyte?

The probability of fruit set in a self-pollinated bisexual flower of a plant is far greater than a dioecious plant explain

What is fruit production without fertilisation called?

Why do you think that the zygote is dormant for sometime in a fertilised ovule?

Name the parts of an angiosperm flower in which development of male and female gametophyte takes place.

Devices for self-pollination are

Pick the odd one out

In angiosperms, pollen tubes liberate their male gametes into the

Egg apparatus consists of

All flowering plants show sexual reproduction. In the flowering plant male, the reproductive part is androecium while the female reproduction part is gynoecium. The male reproduction part consists of filament and anther. the proximal end of the filament attached to the thalamus. A typical end of the filament is attached to the thalamus. A typical angiosperm anther is bilobed. The anther is a four

sided structure consisting of 4 microsporangia appear near-circular in outline. It is surrounded by 4 layers. calls of the sporogenesis anther mature and dehydrated, the microspores dissociate from each

other and develop in the pollen grain. pollen grain Tepresents the male gametophytes. pollen grain made up of two-layer.
1.Wite accessory and essential parts of a flowers.
2.List out four layers of anther wall write its functions
3.Defincd micro sprogcnesis

4.Differentiatc Cxine and intinc

Read the following and answer any four questions from (v) to (v) given below:
A typical angiospermic ovule is a small structure attached to the placenta by means of a stalk called funicle. The body of the ovule fuses with funicle in the region called hilum. Each ovule has one or two protective envelopes called integuments. Integuments encircle the nucellus except at the tip where a small opening called the micropyle is formed. Mature ovules are classified on the basis of funiculus. It can be orthotropous, anatropous, hemitropous, campylotropous, etc.
(i) The body of the ovule consists of a mass of parenchymatous cells called

(ii) Refer to the given figure and select the correct statement regarding it.

(a) This type of ovule is found in cactus.
(b) The micropyle comes to lie close to the funiculus due to unilateral growth of ovule.
(c) It is most common type of ovule found in the members of Chenopodiaceae
(d) It is half inverted ovule.

(iii) Identify the parts labelled as A, B, Cand D in the given figure and select the correct option

(iv) Mature ovules are classified on the basis of funiculus. If micropyle lie close to the funiculus, the ovule is termed as

(v) In Asphodelus, ovule is

The diagram of an anatropous ovule is presented above.
(a) Give the technical term for ovule.
(b) Identify and name the part that
(i) attaches the ovule to the placenta
(ii) remains as perisperm in some seeds.
(iii) forms the testa of seed.
(iv) represents the basal part of the ovule.
(v) represents the female gametophyte.

The pollen grains may be shed at the two-celled stage (as in 60 per cent of angiosperms) or in the three-celled stage (as in the remaining species). When once shed, the pollen grains must land on the correct type of stigma before they lose viability, to effect fertilisation.
(a) The period for which the pollen grains remain viable is highly variable depending on the species. Substantiate the statement with two examples.
(b) Mention two environmental factors, which affect the pollen viability.