Pollination by bees is called mellitophily.

A diploid embryosac is formed from megaspore mother cell without a regular meiotic division
Example:
Eupatorium, Aerva

Individuals formed by asexual reproductive methods are morphologically and genetically identical and are called clones.

Sucker - chrysanthemum
Stolon - jasmine

Reproduction is a biological process in which an organism give rise to offsprings. This helps to maintain continuity of its species.

Supplies nutrition to the developing microspores contributes sporopollenin through, ubisch bodies. This plays an important role in pollen wall formation. The pollen kit material is contributed by tapetal cells, and is later, transferred to the pollen surface. Exine protein responsible for rejection reaction are derived from tapetal cells.

In some species (unitegmic, tenuinucellate) the inner layer of integument becomes specialized, The layer is nutritive in function for the embryosac. This layer is called endothelium or integumentary tapetum.
Example:
Asteraceae.

Mound Layering	Air Layering
A lower flexible branch of the plant is selected.	A healthy, stiff branch of the plant is selected.
The branch is bent to the ground.	The stem is girdled at the nodal region hormones applied.
A part of the branch is buried in the soil leaving the tips exposed and allowed for rooting	The girdled portion is covered with Damp or moist soil and allowed for rooting.

  Grafting Layering Types Types of grafting Bud/Approach/Tongue
Crown/Wedge Types of layering mound / Air Benefits More useful to get more varieties from a single Plant Can get only one type of offspring Usage More useful in horticultural filed Less useful technique in horticultural field Result Can get highly desirable characters from parent stock to different scion Can get same characteristics from parent to offspring

Dicot Seed	Monocot Seed
Seed coat differentiated into outer hard testa, inner thin membranous tegmen.	Seed coat brownish membranous unilayer closely adhered to the grain
Two cotyledons, laterally attached to the embryonic axis	Embryo consists of one shield shaped cotyledon, the scutellum
The reserve food materials stored either in cotyledon or in endosperm	The reserve food materials stored in the endosperm.
Embryonic axis is differentiated into radicle and plumule but not protected by any sheath	Embryonic axis is differentiated into radicle and plumule Radicle is protected by Coleorhiza Plumule is protected by Coleoptile
Example - Cicer arientinum	Example - Oryza sativa

(i) A mature ovule (megasporangium) consist of a stalk and a body
(ii) Funicle - The stalk of the ovule by which it attaches the ovule to the placenta.
(iii) Integuments - one or two protective covering around the nucellus
(iv) Micropyle - Pore present at the tip of the ovule where the integument is absent
(v) Chalaza - The basal region of the body of the ovule where the nucellus, the integument and funicle meet or merge
(vi) Embryosac- The female gametophyte oval sac like structure in the nucellus, toward the micropylar end.

 

Advantages of modern methods
(i) Plants with desired characteristics can be multiplied rapidly in a short duration.
(ii) Plants produced are genetically identical.
(iii) Tissue culture can be carried out in any season.
(iv) Plants which do not produce viable seeds and seeds that are difficult to germinate can be propagated. 
(v) Rare and endangered plants can be propagated. Disease-free plants can be produced cells can be genetically modified and transformed.