PlantsStd: 6Sb.3, 6Sb.4January 2013Ms. Butler

Plant Characteristics• Size varies • Most have a root like structure• Adapted to every environment on

Earth• All need water•Some require to be submerged•Either saltwater or freshwater

Plant Cell• Membrane • Nucleus• Other cellular structure•Provide structure•Protection

• Many contain green pigment chlorophyll•Found in structure called chloroplast•Use to make food through a process called photosynthesis

Origin and Evolution of Plants

Green Algae• Probably originated from one-celled ancient green

algae from the sea.• One celled and/or many celled organism• Have some types of chlorophyll and carotenoids• Carotenoids• red, yellow, or orange pigments • used for photosynthesis• Algae BrainPop

Life on Land

Protection and Support• Cuticle• Secreted by cells onto the surface of the plant• Slows loss of water which enables the plant to live on land• Chemical compound

• Cellulose• Long chains of cellulose molecules form tangled fibers in

plant cell walls provide structure and support

• Other cell wall substances• Wood used for construction because of strong cell walls• Each plant cell is surrounded by water

Reproduction

• Water resistant spores helped plants reproduce successfully

• Others adapted by producing water – resistant seed in cones or in flowers that developed into fruit

Classification of Plants

• Into major groups called divisions

• Another way to group is vascular or nonvascular

• Naming plants• Binomial nomenclature• Unique two word name

• Phylogeny- the evolutionary history of an organisms on how it has changed over time• Kingdom – 1st and

largest• Phylum• Class • Order• Family• Genus• Species

Classification

Seedless Plants BrainPop

Seedless Plants

NonVascular

Vascular

Plants

No-Seeds

Mosses

Lichens

Not A Plant

Fungi / Lichen, Mushrooms

No Seeds

Ferns

Horsetails

Seeds

Gymnosperms

Conifers

Angiosperms

Monocots

Dicots

Seedless Nonvascular Plants

• Very small plants• Have rhizoid instead of roots• Water absorbed directly into the cells • Grow in damp environments• Reproduce by spores•Ex. Mosses, liverworts, hornworts

Seedless Vascular (SLV)• Reproduce by spores, but have vascular tissue• Can grow bigger and thicker than nonvascular

plants (NV)• Ferns are the largest group • Have stems, leaves and roots• Leaves called fonds• Reproduce by fonds on back of the leaves

• Club mosses • Needlelike leaves• Ex. Ground pines and spike mosses• Spores at the end of the stem structure• BrainPOP | Science | Learn about Seedless Plants

• Decaying seedless plants are compressed into peat and eventually coalSoil conditioners

Why Are They Important?FUEL!

Where would we find a NV plant?

Seed Plants (VS)• What are they?• Ex. Peanut butter, jelly, carrots• Leaves

• Most have • Where photosynthesis usually occurs• Leaf cell structure• Many layers • Most have stomato – surrounded by two guard cells that

open/close for gas exchange

• Stems• Exchange materials• Herbaceous or woody – usually soft and green• BrainPop Seed Plants

SV con’t. • Roots• Have vascular tissue to move material • Act as anchors• Store food/water• Carrots• Beets

• Absorb O2 through respiration

Vascular Tissue• 3 tissues• Xylem – move material and support plant• Phloem – move food from production to storage• Cambium

• Gymnosperms “naked seed”• Oldest trees alive• VS plants• Produce seeds not protected by fruit

• Angiosperms• SV flower plant • Flowering plants with seeds protected in vessels• In the Anthophyta division which is more than ½ of the

known plants• Flowers

Angiosperms

DicotsMonocots

Monocots and Dicots• Cotyledon - A leaf of the embryo of a seed plant,

which upon germination either remains in the seed or emerges, enlarges, and becomes green. Also called seed leaf.

• Monocots• Comprise a quarter of flowering plants• Most economically important• Have an embryo with one cotyledon• Ex. Corn, rice, wheat, banana, pineapple, dates

• Dicots• Have an embryo with two cotyledons• Most shade trees• Ex. Peanut, green beans, peas, apples and oranges

Life Cycle of Angiosperms• Biennials - Produce seeds and plants only during

their 2nd year of life• Perennials• Take 2 years to grow to maturity• Herbaceous • Appear to die in winter and grow back each year• Ex. Fruit trees on stems that provide over many years

Plant Growth and Development• Photosynthesis • the process of capturing light energy and converting it to• sugar energy, in the presence of chlorophyll using CO2 and H2O,

• Respiration • the process of metabolizing (burning) sugars to yield• energy for growth, reproduction, and other life processes

• Transpiration – the loss of water vapor through the stomata of leaves

• Photosynthesis/Respiration Song