Question

Write about Angiosperm .

Answer 1

Hi.



here is your answer. ..





Unlike the gymnosprm where the ovules are naked, in the angiosperm or flowering plants, the pollen grains and ovules are developed in specialised structure called flowers. In angiosperm the seeds are enclosed by fruits. The angiosperm are in exceptionally large group of plants occurring in wide range of habitats. They range in size from tiny, almost microscopic wolfia to all tsll trees of eucalyptus. they provide us with the food, fooder , fuel, medicines and several other commercially important products.



They are divided into two groups :---

●Dicotyledons

● Monocotyledon.



Dicotyledons having 2 cotyledon in their seeds while the Monocotyledon have 1 seed in their.
The male sex organ in flower is the stamen. Each stamens consists of a slender filament with an anther at the tip.The anthers following meiosis produces pollen grains. The female sex organs are carpel. and pistil .Pistil consists of an ovary enclosing one to many ovules. Within ovules are present highly reduced female gametophyte term embryo sacs.


The embryo sac formation produced by meiosis. hence each cells of the embryo is haploid.



hope it helps you ☺

Answer 2

Here is answer about your question


* ANGIOSPERMS are flowering plants.

* It's ovules and pollen grains are developed into a special structure called flower.

* It's seeds are enclosed by fruits.

~ Types of angiosperms are :-
I. Monocotyledons.
2. Dicotyledons.

1. Monocotyledons :- flower having single cotyledons are known as monocotyledons.

2. Dicotyledons :- flowers having double cotyledons are known as dicotyledons.

In flower female parts consists of stigma, style and ovary. Ovary contains ovule.
Male parts consists of long stalk part filament and the upper broad portion called anther. Anther contains pollen grain.
During pollination when anther fuse on stigma it releases two pollen grains (male gamates). Pollen grains on reaching stigma secrete some liquid substance. Stigma absorb this substance and grow longer and longer and form Pollen tube. This pollen tube ultimately reach the ovule.
Two Pollen grains (male gamates) travel through Pollen tube to ovule.
Ovule contains egg. When male gamate fuse with egg then it forms zygote.
Another male gamate fuse with two polar nuclei this fussion is known as triple fussion. Then it forms triploid primary endosperm nucleus.
Since, the fussion occurs two times. So, it is known as DOUBLE FERTILIZATION.
After this zygote develops into embryo and triploid primary endosperm nucleus into endosperm which provide nourishment (food) to developing embryo.
After this ovary develop into fruit and ovule into seed.

* Life cycle of angiosperm :-

Plants have both sporophytic and gametophytic generations which ulternate with each other to complete the life cycle. Ulternation of spore producing diploid sporophyte with the haploid gametophyte is called ulternation of generation.


Hope it helps you.