Seed Plants and Angiosperms Overview

Angiosperms

Flowering plants that produce seeds enclosed within a fruit.

Gymnosperms

Seed plants that do not form flowers; their seeds are exposed on cones.

Double Fertilization

A process in angiosperms where one sperm fertilizes the egg and the other fuses with two polar nuclei to form triploid endosperm.

Endosperm

Tissue that nourishes the developing embryo in seeds, formed from the triploid cell during double fertilization.

Heterospory

The production of two distinct types of spores (microspores and megaspores) by seed plants.

Pericarp

The outer layer of a fruit, developed from the ovary wall; consists of exocarp, mesocarp, and endocarp.

Monocots

Angiosperms with one cotyledon (seed leaf), including grasses and lilies.

Eudicots

Angiosperms characterized by two cotyledons; they include most flowering plants.

Inflorescence

A cluster of flowers arranged on a stem.

Perfect Flowers

Flowers that contain both stamens and carpels.

Imperfect Flowers

Flowers that are either male (only stamens) or female (only carpels).

Aggregate Fruits

Fruits formed from a single flower with multiple carpels, such as raspberries.

Multiple Fruits

Fruits that develop from a cluster of separate flowers, like pineapples.

Monoecious Plants

Plants that have both male and female flowers on the same individual.

Dioecious Plants

Plants that have either male or female flowers, but not both, on separate individuals.

Central Cell

Cell in the female gametophyte that participates in double fertilization, leading to endosperm formation.

Floral Organs

Structures of a flower, including sepals, petals, stamens, and carpels.

Calyx

Collective term for all the sepals of a flower.

Corolla

Collective term for all the petals of a flower.

Stamen

Flower structure that produces pollen, consisting of a filament and anther.

Carpel

The female reproductive part of a flower, containing the ovary, style, and stigma.