Sexual Reproduction in Flowering Plants

These flashcards cover key terms and definitions related to sexual reproduction in flowering plants, as outlined in the class notes.

Angiosperms

Flowering plants that show sexual reproduction.

Androecium

The male reproductive whorl of a flower, composed of stamens.

Gynoecium

The female reproductive whorl of a flower, consisting of carpels.

Microsporogenesis

The process of formation of microspores from microspore mother cells through meiosis.

Megasporogenesis

The formation of megaspores from the megaspore mother cell, leading to the development of the female gametophyte.

Pollination

The transfer of pollen grains from the anther to the stigma.

Self-pollination

Transfer of pollen from the anther to the stigma of the same flower.

Cross-pollination

Transfer of pollen between different flowers, leading to genetic variation.

Double fertilization

A unique angiosperm process where one male gamete fuses with the egg cell and another with the central cell to form the primary endosperm nucleus.

Endosperm

Nutritional tissue supporting the developing embryo in seeds.

Pollen tube

A tube formed from a pollen grain that carries male gametes to the ovule.

Apomixis

Asexual reproduction that mimics sexual reproduction, allowing for seed formation without fertilization.

Cleistogamous flowers

Flowers that never open and achieve self-pollination.

Filiform apparatus

Special cellular thickenings in synergids that help attract and guide pollen tubes.

Nucellus

Tissue in the ovule that provides nutrition to the developing embryo sac.

Sporopollenin

A resistant substance forming the outer wall of pollen grains.

Viability of pollen grains

The period during which pollen remains capable of fertilizing an ovule.

Microgametophyte

The male gametophyte represented by the pollen grain.

Megagametophyte

The female gametophyte within the embryo sac.

Filament

The stalk of the stamen that holds up the anther.

Stigma

The part of the gynoecium that receives pollen during pollination.

Ovary

The swollen base of the carpel that contains ovules.