Angiosperms: Unit 5, Chapter 31

Angiosperms

Flowering plants that have evolved specialized structures called flowers and fruits.

Flower

A reproductive structure in angiosperms that consists of modified leaves (sporophylls) arranged around a central receptacle.

Perianth

The outermost part of a flower, consisting of sepals and petals.

Sepals

Leaf-like structures at the base of a flower that enclose the unopened floral bud.

Petals

The inner whorl of sepals in a flower that are often brightly colored and attract pollinators.

Gynoecium

The female part of a flower, which includes one or more carpels.

Pistil

The collective term for multiple carpels in a flower.

Stigma

The receptive surface of the pistil where pollen is deposited.

Style

The structure that connects the stigma to the ovary and through which the pollen tube grows.

Ovary

The part of the flower that houses the ovules.

Androecium

The male part of a flower, which includes multiple stamens.

Stamen

The male reproductive structure in a flower, consisting of a stalk (filament) and an anther (pollen sac).

Angiosperm Reproduction

The process of sexual reproduction in angiosperms, involving the fusion of male and female gametes.

Life Cycle of an Angiosperm

The sequence of events from the formation of a zygote through the development of a mature plant.

Double Fertilization

A unique process in angiosperms where one sperm fertilizes the egg to form a zygote, while another sperm fuses with the central cell to form endosperm.

Embryo

The young, developing plant within a seed, consisting of a radicle (small root) and cotyledons (leaf-like organs).

Fruits

Mature ovaries that develop after fertilization, often aiding in seed dispersal.

Ovary Wall

The thickened wall of the ovary that becomes the fruit after fertilization.

Fleshy Fruits

Fruits that have a soft, juicy texture, often consumed by animals for seed dispersal.

Dry Fruits

Fruits that have a hard, dry texture, often dispersed by wind or other means.

Diversity of Angiosperms

The wide range of angiosperm species, classified into different groups based on their characteristics.

Anthophyta

The single phylum of angiosperms, encompassing all flowering plants.

Basal Angiosperms

A group of angiosperms belonging to the magnoliidae subclass, including magnolias, laurels, and peppers.

Monocots

Angiosperms with a single cotyledon, scattered vascular tissue, and no tap root, including lilies, orchids, and grasses.

Dicots

Angiosperms with two cotyledons, flowers in multiples of 4 or 5, and a main tap root, including herbaceous and woody plants.