Chapter 22:

Plant Diversity

Adapted from Prentice Hall

Goal 1: What are Plants?

A. Structure:

–multicellular –eukaryotes –cell walls made of

cellulose

–Use

sugar photosynthesis to make

B. Need to Survive

• Sunlight (for energy) – enters leaves • water

and minerals (nitrogen, etc.)

– enters roots • gas exchange (

need CO 2 & give off O 2 )

– through leaves

C. Groups

1. Seedless a. green algae b.bryophytes

c. Vascular plants (Ferns) 2. Seed a. Gymnosperm (cones) 3. Flowers a. Angiosperms (fruits)

D. Groups Based on: 1. these features: a. water-conducting tissues b. seeds c. flowers 2. also classified by: a. reproductive structures b. body plan

Evolution of the Plant Kingdom Mosses and their relatives Ferns and their relatives Flowering plants Cone-bearing plants Flowers; Seeds enclosed in fruit Seeds Water-conducting (vascular) tissue Green algae ancestor

Goal 2: Seedless Plants

Bryophytes Moss & Fern

A. Bryophytes 1. Also called nonvascular plants

•

do NOT have vascular tissues

•

Vascular tissues = transport water and nutrients through plant

• Examples: mosses

2. depend on water for reproduction 3. draw up water by osmosis

4.

cannot grow taller than inch above the ground an

B. Seedless Vascular Plants A. Have vascular tissue 1. Two types: a. XYLEM plant B. Example: Ferns -

carries water

b. PHLOEM – carries sugar from the roots to every part of a from leaves to every part of a plant

Xylem (H 2 O) Vascular Tissue CO 2 O 2 Light H 2 O Sugar Phloem (sugars) H 2 O Minerals

Goal 3: Seed Plants

I. Seeds

A. an embryo of a plant

– embryo = organism in its early stage of

development. (“baby” plant) B. Embryo is surrounded by a food supply and protective covering

– Protected by a

seed coat surrounds and protects the embryo

Internal Structures of a Seed

C. Two plant groups:

•Gymnosperms – seeds on the surfaces of

cones

– Examples: cycads, ginkgoes, conifers •Angiosperms – seeds within a layer of

tissue (fruit) that protects the seed

Conifers – Cone Bearers

Goal 4: Angiosperms— Flowering Plants

A. Flowers and Fruits 1. flower = reproductive organ for plant a. attract animals, insect, etc.

i. animals transport pollen from flower to flower

» Pollen – male sperm

Flowers and Fruits ii. contain ovaries

• Holds female egg • surrounds and protect the seeds

after pollen reaches egg

• ovary turns into a

seed.

»

transport seed fruit = a wall of tissue that surrounds a protects the seed and helps

Flower Anatomy

B. Groups of Angiosperms

– can belong to

more than one category 1. Monocots & Dicots a. Monocots = one seed leaf, parallel leaf veins, flower petals in 3 or 6, tissues scattered in stem, fibrous root b. Dicots = two seed leaves, branched veins, flower petals in 4 or 5, tissues in ring, taproots

Diversity of Angiosperms

2. Woody and Herbaceous Plants:

• herbaceous

stems = smooth, green

• woody plants

= brown bark

– Ex:

vines trees, shrubs, and .

3. Annuals, Biennials, and Perennials

•Represents how long the plant lives •determined by

genetic and environmental factors .

a. Annuals = live only one year

b. Biennials = live for two years

c. Perennials =

•live for more than two years