Gymnosperms vs. Angiosperms

Exposed Seed Plants (Gymnosperms) vs. Flowering Plants (Angiosperms) Gymnosperms – bear seeds directly on surfaces of cones (conifers such as pines and spruces) Angiosperms – bear seeds within a layer of protective tissue (grasses, trees, flowers)

Comparing Features of Seed Plants Seeds Reproduction Examples Gymnosperms Angiosperms Bear their seeds on cones Can reproduce without water; male gametophytes are contained in pollen grains; fertilization occurs by pollination Conifers, cycads, ginkgoes, gnetophytes Bear their seeds within flowers Can reproduce without water; male gametophytes are contained in pollen grains; fertilization occurs by pollination Grasses, flowering trees and shrubs, wildflowers, cultivated flowers

Seeds Seed plants can live just about anywhere due to the seeds A seed is an embryo of a plant encased in a protective covering surrounded by food Seed coat protects embryo and prevents the seed from drying out Seed coat Embryo Stored food supply Seed Wing B A

Seed Dispersal Seed dispersal is varied Some seeds stick to fur/hair/clothing Some seeds have “wings” for “flying” in the wind or floating on water Other seeds are surrounded by fruit (ovary of the plant) to help the seed to be eaten and ultimately dispersed somewhere else

Gymnosperm (“naked seed”) Reproduce with seeds that are exposed No flowers and are pollinated by wind or water Typically produce cones Include cycads (palm-like plants), ginkgo, conifers (pines, spruce, cedar trees)

Examples of Gymnosperms

Angiosperms (“enclosed seed”) Flowering plants – vast majority of plants reproduce with flowers Flowers attract pollinators that transport pollen from flower to flower Colorful and fragrant flowers are pollinated by animals Flowers are reproductive organs that contain ovaries which surround and protect the seeds After pollination, the ovary develops into a fruit Seeds inside the fruit are dispersed by the animals that eat them

The Structure of a Flower Filament Anther Stigma Style Ovary Carpel Petal Sepal Ovule Stamen

Apple Fruit Development

Comparing Wind-pollinated and Animal-pollinated Plants Characteristics Pollination method Relative efficiency of pollination method Plant types Reproductive organs Adaptations that promote pollination Wind-pollinated Plants Wind pollination Less efficient Mostly gymnosperms and some angiosperms Cones Pollination drop Animal-pollinated Plants Vector pollination More efficient Angiosperms Flowers Bright colors, sweet nectar

Diversity of Angiosperms Many different categories Monocots and dicots Woody and herbaceous Annuals, biennials, and perennials Some categories can overlap

Monocots vs. Dicots Monocots - one seed leaf (cotyledon) Parallel veins, flower parts in multiples of three, fibrous roots Ex. Corn, wheat, lilies, orchids, palms

Monocots vs. Dicots (continued) Dicots – two seed leaves Branched veins, flower parts in multiples of four or five, taproot Ex. Daisies, clover, oak trees, tomatoes, roses

Monocots vs. Dicots Monocots Dicots Single cotyledon Parallel veins Floral parts often in multiples of 3 Vascular bundles scattered throughout stem Fibrous roots Two cotyledons Branched veins Floral parts often in multiples of 4 or 5 Vascular bundles arranged in a ring Taproot Seeds Leaves Flowers Stems Roots

Monocots vs. Dicots Seed Germination in Monocots Dicots have have 1 Cotyledon 2 Cotyledons that that Remains with the seed Emerge above ground Remain below ground

Monocots vs. Dicots

Woody vs. Herbaceous Woody – strong stems like those of trees, shrubs, and vines Herbaceous – non-woody stems such as those of dandelions and sunflowers

Annuals, Biennials, and Perennials Annuals – complete their life cycle in one year (many summer garden plants) Biennials – complete their life cycle in two years (some summer garden plants) Perennials – live for more than two years (shrubs, trees, grass, etc.)