Enterprise: Plant Science Unit: Basics of Plant Science Factor: Information Needed I. Struct- ures A.Root systems 1. Taproot- one main root that grows.

Enterprise: Plant ScienceUnit: Basics of Plant ScienceFactor: Information NeededI. Struct-ures

A.Root systems 1. Taproot- one main root that

grows straight down.a. used for food (carrots,etc)b. drought tolerant

2. Fibrous root- many small roots.a. tie up soil (many grasses)b. not as drought tolerant

3. Adventitious roots- specialized roots that develop .

B. Stems- there are many types.1. Woody- tough and winter hardy2. Herbaceous- green and die back.3. Modified stems (specialized)

a. bulbs- onions, Easter liliesb. corms- thickened stemsc. rhizomes- horizontal

underground stemd. tuber- potatoe. stolon- (runner) above ground

horizontal stem (strawberry)C. External stem parts:

Stem Part ID

Terminal Bud (false)

Lenticels

Bud scales

Leaf scar

Bundle Scar(Small dots)

Auxiliary bud

Terminal Bud(true)

Node &Internode

D. Internal stem & root structures:1. Xylem- carry water & minerals

up.2. Phloem- carry food and nutrients

down.3. Structures differ for subclasses:

a. monocotyledon- xylem and phloem are in separate rings.(grasses)b. dicotyledon- xylem and phloem in vascular bundles. (broad leaved plants)

E. Leaves- manufacture food through photosynthesis

1. Leaf shapes, margins, tips, and bases are important for identification purposes.

2. Leaf arrangements are also important identifiers:

a. Simple- alternate, opposite, whorled.

b. Compound- palmate, pinnate, Bipinnate.

3. The simple leaf parts include:

Tips

Lobe

Sinus

Petiole

Midrib

Margin

Base

Raised glandStipule

Incised Leaf parts

Leaf parts

F. The flower is the sexual part of the plant.

1. The male part is the stamen.2. The female part is the pistil.

a. perfect flowers contain both male and female parts.

b. an imperfect flower has only male or female parts, not both.

3. Flowers become fruits, nuts, or seeds.

II. Physi-ology

A.Physiology is the study of function.1. Understanding plant function will allow success in growing them.

B. Photosynthesis:1. Is the process in which light energy is converted into stored chemical energy (sugar).2. Carbon dioxide + water in the presence of chlorophyll and light form sugar, oxygen, and water

a. chlorophyll is the green pigment in plants

C. Respiration is the process of breaking down sugar into heat energy.

1. Sugar and oxygen are used by the plant to produce energy. Carbon dioxide and water are by-products. D. Transpiration is the process of losing water vapor through stoma

1. Plants wilt if too much water is transpired.E. Osmosis is used by the plant to bring in water and nutrients

III. Plant Nutrition

A. Plants require certain chemicals and soil pH to grow successfully.

B. There are 16 nutrients needed for plant growth.1. “C. Hopkin’s café, mighty good.”stands for: carbon, hydrogen, oxygen, phosporus, potassium, nitrogen, sulfer, calcium, iron, and magnesium. The others are boron, copper, chlorine, manganese, molybdenum and zinc.

2. The three that are fertilized for the most often are Nitrogen (N), Phosphorus (P), and Potassium (K). a. A 15-24-50 fertilizer would have 15% N, 24% P, and 50%K.C. pH is the measure of acidity or alkalinity of the soil.

1. pH of 7 is neutral2. Below 7 is acidic, lime is added to

raise it towards 7.3. Above 7 is alkaline, sulfur is added

to lower it closer to 7. 4. Most plants like a pH of 6 to 7.

IV. Plant Repro

A.Reproducing plants is often referred to as propagation. There are two basic types:

1. Sexual propagation- seeds

a. germination-

2. Asexual propagation

B. Asexual propagation methods include

1. Stem cuttings- uses pieces of the stem

2. Leaf cutting- works on many indoor houseplants

3. Root cuttings are used on older plants with large root systems in the dormant season

4. Layering- is the process of using a stem while it is still attached to the plant.

5. Division- is the process of cutting the main plant into several pieces

6. Grafting- a piece of one plant is attached to another plant.

7. Tissue culture- done with small pieces in a laboratory setting.