Biology Lessons Part 2: Population Biology

Lesson 2.6 Glossary: How Do Flowering Plants Reproduce?

angiosperms - flowering plants.

anther - in flowers, the end part of the male stamen that produces grains of pollen.

carpel - a structure that encloses an egg in angiosperms, composed of ovary, style, and stigma.

cotyledon - the endosperm in a seed that develops into a seedling.

cross-fertilization - the fertilization of a female egg by pollen which did not come from the same plant.

dicot - the larger of the two classes of angiosperms characterized by having two cotyledons, floral parts that occur in multiples of four or five, and net-veined leaves. Examples of dicots are maple trees and tomato plants.

egg - the female gamete (haploid sex cell derived by meiotic division).

endosperm - triploid (containing three sets of chromosomes) nourishing tissue in the seeds of angiosperms.

filament - the long shaft of a stamen atop which the anther is attached.

fruit - the ripe, mature ovary containing seeds.

gametes - specialized sex cells in plants, such as eggs and pollen. Gametes are haploid. A male gamete and a female gamete fuse and give rise to a diploid zygote, which develops into a new individual.

imperfect flowers - flowers containing either male or female parts, but not both; therefore, imperfect flowers are incapable of self-fertilization. The same plant may contain both male and female flowers, however. The corn flower is an example of an imperfect flower.

monocot - the smaller of the two classes of angiosperms characterized by having one cotyledon, floral parts which occur in multiples of three, and leaves that are parallel veined. Examples of monocots include lilies and trillium flowers.

ovary walls - the tough walls surrounding the egg in a developing fruit or vegetable.

perfect flowers - flowers containing both male and female parts. Examples of perfect flowers are tulips and hybiscus.

petals - specialized leaf structures that protect the sex organs of a flower and direct insects and birds to assist in fertilization.

pistil - a single carpel or a group of fused carpels; the female parts of a flower composed of ovary, stigma, and style.

pollen - the male gamete of a flowering plant which typically contains two sperm nuclei capable of fertilizing an egg.

receptacle - structure at the base of a flower which attaches the flower style to the stem. The receptacle will often break down in a fertilized, mature flower to aid in dispersal of seeds.

seed - the product of a fertilized egg of a seed plant, generally consisting of an embryo with its food reserves encased in a protective coat.

self-fertilization - the fertilization of a female egg by pollen which come from the same flower.

sepal - the green leaf-like structures that cover a bud and later open up to reveal the petals of a flower.

sperm nuclei - haploid male nuclei which are encased in a pollen grain.

stamen - the male reproductive structure in a flower; consists of anther and filament.

stigma - the sticky top of a carpel or a pistil that serves as a pollen receptacle.

style - a structure leading from the ovary of flowering plants to the stigma.

zygote - the diploid cell that results from the fusion of an egg and a pollen cell.