The Plant KingdomThe Plant Kingdom

Chapter 1Chapter 1

Evolution of Plants• 3.5 billion years ago = bacteria &

blue/green algae.• 1 billion years ago = green algae• 600 million years ago = 02 could

support life.• 400 million years ago = land

plants.• 350 million years ago = seed

plants.

Geographical Distribution

• All over the earth with few limiting factors which are:

• Climate– Water– Temperature

Roles of Plants

• Photosynthetic Process

• Autotrophs

• C02 and H20

• Sunlight & Chlorophyll

• Glucose, O2, & H20

• Energy Capture

Food (Edible Plants)

• What parts of a plant do we eat?• Roots • Stems• Leaves• Flowers• Seeds (Cereal Grains)• Fruits• Tubers

Edible Plants

• Sugar• Angiosperms

– Largest amount of plants we eat come from this classification.

Industrial Uses

• Wood– Houses, furniture, turpentine

• Fibers– Cotton, flax, hemp,

• Oils– Soybean, coconut, cottonseed,..

• Rubber

Medicinal Uses

• Health benefits• Most pharmaceuticals• Antibiotics

Other Uses

• Fossil Fuels• Prehistoric Plants-captured solar

energy• Oil and Gas• Buried Plant material that has

undergone chemical changes

Animal –vs- Plant Kingdoms

• Mobile• Need to feed

themselves • Lack a cell wall of

cellulose (flaccid)• Cellulose not

synthesized• Growth is limited

• Generally not mobile• Contain chlorophyll

to make own food• Cell walls made of

cellulose• Cellulose

synthesized by cells• Growth is unlimited

Kingdom Plantae• 500,000 kinds of plants exist.• Many don’t fit well.• Recent trends based on evolutionary

origins & Relationship.– Monera; the bacteria & blue green algae.– Protista; all other algae & the protozoans.– Mycota, fungi; such as mushrooms &

molds– Plantae; mosses, ferns, seed plants &

several minor groups.

Taxonomy

• Theophrastus (370-285 B.C) started to record names.

• Used Common Names.

• Cause confusion

Plant Classification

• There must be a systematic method to evaluate the species of the planet consistently. There are many ways.

• Nomenclature is the system of assigning names.

Nomenclature

• Scientific communities use Latin,Greek, and Arabic to name

• Names are use to signify origins or characteristics

• For example: names for leaves are phylla, follia, phyllon, folius

• Prefixes are also used: micro-small macro-large

• Microphylla, Magnolia grandiflora

Classification

• Carl von Linne is the creator of the classification system by the publication of Hortus in 1732

• Binomial – Two names the Genus and the species. Genus always capitalized and species lower case and both should be italicized.

How to Classify Plants

• Phylogenetic = How they look• Environmental = where they grow

(climate regions)• Agricultural = What use they are

grown for• Natural/morpholigal = how their

structures compares

Artificial Classification Systems

• Climatic• Agricultural

Botanical Systems

• Structure of the plants

Example of a complete classification of an Onion

plant.Kingdom: Plantae Division: Anthophyta Class: Monocotyledonae Order: Liliales Family: Amaryllidaceae Genus: Allium Species: Allium cepa L

Divisions or phylla• Thallophyta - algae, and fungi no

tissue differentiation.• Bryophyta – green plants w/o true

roots or flowers. Mosses & liverworts • Pteridophyta - green plants with

vascular system, true roots, usually distinct leaves & stems but no true flowers or seeds, has spores

• Spermatophyta – plants with true flowers producing seeds.

Further Separation

• Spermatophyta-further divided: gymnosperms & angiosperms– Gymnospermae = naked seed (in

cones)– Angiospermae = seed protected

• Subclasses-Angiosperms: Mono & dicotyledons

Class

• Monocotyledoneae = one cotyledon, generally parallel veins, flower parts in 3’s & 6’s.

• Dicotyledoneae = two cotyledon, net-veined leaves, flower parts

in 4’s & 5’s or multiples of 4’s & 5’s

Lower Subdivisions

• Order• Family• Genus• Species

• Form• Variety/Cultivar/Clone

Sub specific Categories

• Botanical Variety-different from wild hence var..

• Cultivar-little genetic variation “cv”

• Hybrid-crossbreeding use an “x”

• Family-closely related genera nightshade, sunflower

New Taxonomic Tools

• Chemical analysis – composition of the plant

• Protein analysis• DNA analysis – genetic finger

printing.