Plant Diversity

Page
5

Slide 45

Angiosperms—Flowering Plants

Slide 46

Flowers and Fruits

Flowers and Fruits

Angiosperms develop unique reproductive organs known as flowers.

Slide 47

Flowers and Fruits

Flowers are an evolutionary advantage because they attract animals, which then transport pollen from flower to flower.

Flowers contain ovaries, which surround and protect the seeds.

After pollination, the ovary develops into a fruit.

A fruit is a wall of tissue that surrounds a seed. A fruit protects the seed and aids in its dispersal.

Slide 48

Flower Anatomy

Slide 49

Diversity of Angiosperms

Angiosperms are categorized in many ways:

monocots and dicots

woody and herbaceous plants

annuals, biennials, and perennials

An angiosperm can belong to more than one category.

Slide 50

Diversity of Angiosperms

Monocots and dicots are named for the number of seed leaves, or cotyledons, in the plant embryo. Monocots have one seed leaf, and dicots have two.

A cotyledon is the first leaf or the first pair of leaves produced by the embryo of a seed plant.

Slide 51

Diversity of Angiosperms

Slide 52

Slide 53

Diversity of Angiosperms

Woody and Herbaceous Plants:

Plant stems that are smooth and nonwoody are characteristic of herbaceous plants.

Woody plants include trees, shrubs, and vines.

Slide 54

Annuals, Biennials, and Perennials

There are three categories of plant life spans

Annual

Biennial

Perennial

Plant life span is determined by genetic and environmental factors.

Slide 55

Diversity of Angiosperms

Annuals are plants that complete a life cycle in one growing season.

Slide 56

Biennials complete their life cycle in two years.

In the first year, they germinate and grow roots, short stems, and sometimes leaves.

In the second year, they grow new stems and leaves, produce flowers and seeds, and die.