Tag: structure of ovule

Those ovules in which the funicle, chalaza and micropyle lie in one straight line are called orthotropous ovules. Example, Urticaceae.

Egg cell is inside the embryo sac in the ovule. The embryo sac is further enclosed by the parenchymatous tissue, nucellus, which provides nutrition to developing embryo. Nucellus is ultimately surrounded by integuments.

In seed plants, the ovule ("small egg") is the structure that gives rise to and contains the female reproductive cells. It consists of three parts: The integument(s) form its outer layer(s), the nucellus (or remnant of the megasporangium), and female gametophyte (formed from haploid megaspore) in its centre. Mature ovules i.e. megasporangia in angiosperms are mainly of five types. The principle of classification is based on the position of the micropyle, chalaza and hilum with regard to one another and also to the placenta.

The ovule is the structure that gives rise to and contains the female reproductive cells. The megaspore is produced inside the nucleus of the ovule. During megasporogenesis, the megasporocyte or megaspore mother cell, undergoes meiosis to produce initially four haploid cells (the megaspores). After megasporogenesis, the megaspore develops into the female gametophyte (the embryo sac) in a process called megasporogenesis

The carpel is one of the leaflike, seed-bearing structures that constitute the innermost whorl of a flower. The seeds of flowering plants are enclosed inside an ovary which contains ovule. The ovary is part of a flower's female reproductive structure called a carpel. A flower can have one or more carpels. If there are many carpels, they can be separate or fused together. Together, all the carpels are called a gynoecium, or a pistil.

The synergid cell wall forming an extremely thick structure at the micropylar end is called the filiform apparatus. It bears several finger-like projections into the structure of synergid cytoplasm. The function of filiform apparatus is to guide entry of pollen tube and release of sperm cells. 

A small opening formed by inner/both/outer integument and enclosed by ovule integument/s is called as micropyle. It serves as entry point of pollen tube into ovule. Option B is correct. Seed is a small embryonic plant that develops from fertilised ovule. A typical seed has seed coat, endosperm and embryo. Option A is incorrect. The basal swollen part of pistil represents ovary. It has ovarian cavity with one/more locules and a parenchymatous cushion, i.e., placenta that bear ovule. Option C is incorrect. The terminal receptive part of pistil is termed as stigma that serves as landing platform for pollens during pollination. Option D is incorrect. 

paddy, mango and wheat possess single ovule in each ovary whereas papaya, watermelon and orchids contain many