Plants• How are

plants used in maintaining good health?

Medical Plant Project• Student

Project:– Identify a plant

that can be used as a treatment for illness or as a supplement to support good health.

Medical Plant Project• Research the cultural and historical

use of your selected plant as a medical treatment.

• Review and list multiple sources to understand the effectiveness of your plant.

Medical Plant Project

• Follow hand-out for further information.

• You must make a visual presentation.

• Use Animoto or other format.

• Music is OK.

Plants• Plant medical property project:• You may work with one to two other

students.• Project is due April 22. Outline due April 15.

• Will count as a test grade.

Medical Plants Rubric• History, location of origin, medical

properties, how it helps people will be required.

• 50% oral and visual presentation, 3 minutes in length. Any format.• 50% written presentation

including grammar, spelling, and neatness. Must be typed.

Plants• Question: What is a plant?

• Question: What are some characteristics of plants?– Size: Microscopic to more than a football

field in height (+300ft).

– Most have roots or root-like structures.

– Require water.

Parts of The Plant

• Question: What is the largest part of a plant?–Roots

Roots• Question: What is the purpose of roots?

• Transport water and other substances.– Anchor– Support – Store food Video: Roots 1:43

Roots

2 Types of Root Systems

Taproot System

Primary root grows down from the stem with some small secondary roots forming

Examples: Carrots & Turnips

Roots

Fibrous SystemSmall lateral roots that spread out just below the soil’s surface

Examples: Corn & Beans

Parts of the RootEpidermis

Cortex

Outermost layer of cells

Tissue inside epidermis that stores starch and other substances necessary for the growth of the root

Parts of the Root

Root Hairs

Vascular Tissue

Site of absorption

Contains cells that transport water, nutrients, and minerals to all parts of the plant

Root Cross SectionVideo: MSB How plants get water 2

Leaves

BladeMain body of leafPetiole

Attaches blade to stem

Midrib

Large central vein

Leaf Cell Layers• Epidermis: Upper and lower surface of

a leaf.

• Waxy cuticle: coats Epidermis.

• Stomata: Opening in leaf to allow;– What gases to enter the leaf?

• Carbon dioxide to enter– What gas to exit the leaf?

• Oxygen to exit the leaf.

Leaf Cell Layers• Guard Cells: Two guard cells

surround each stoma to open and close it.

• Video: Plant Cells 3:25, Types of plant cells 2:43

Stomata in Leaves• Stomata open and close, which allows

gases into and out of a leaf. This lab will allow you to see some stomata.

1. Bend the piece of lettuce in half and carefully use a pair of forceps to peel off some of the epidermis, the transparent tissue (cuticle) that covers the leaf.

2. Prepare a wet mount of this tissue.

3. Examine your prepared slide under low and high power on the microscope.

Stomata in Leaves 4. Count the number of stomata in your field

of view and then count the no. of open stomata. Enter this no. in your lab report.

5. Make a second slide of the lettuce leaf using a salt solution.

6. Repeat steps 4 and 5.

7. Calculate the percent of open stomata:

no. of open stomata/total no. of stomata

Stomata in LeavesConclude and Apply

In your lab report answer the following questions prior to turning in.

• Determine which slide preparation had a greater percentage of open stomata.

• Infer why fewer stomata were open in the salt-solution mount.

• What can you infer about the function of stomata in a leaf?

Plants• Leaves: Where the food making

process occurs.– What is the name of that process?

• Photosynthesis– We will study photosynthesis in great depth later.– Question: What is the plant in the middle picture?

Plants• Leaf Cell Layers

Leaf Cross Section

Leaf Cell Layers• Just below the epidermis is the palisade

layer where most of the food is produced.• Video: Leaves 2:52

Important Functions of Leaves

PhotosynthesisProcess that plants use to produce their food

6CO2 + 6H2OC6H1206 + 6 O2

TranspirationLoss of water and exchange of carbon dioxide

Functions of the Stem

1. Transports water and nutrients from roots to leaves2. Supports leaves, fruits and flowers

3. Food Storage•Video: Stems 3:16

Stem Cross SectionVideo Roots, Stems, Leaves 1:10

Fruit’s FunctionSite of seed production

Flower Parts

PistilFemale part of plant

Consists of:

•Stigma

•Style

•Ovary

Flower Parts

StamenMale reproductive organ

Flower Function

Sexual Reproduction is the flowers sole function.

Pollination by:

Wind

Insects and BirdsVideo: Flowers :31

Plants• Question: Why do plants have cell

walls and animals do not?

• Most plants have a green pigment called

chlorophyll.• Question: What do plants use

chlorophyll for?

–Chlorophyll is used to make food in a

process called photosynthesis.

• Chlorophyll is found in a cell structure

called a chloroplast.

• Water is important for plants.

• What adaptations would help a plant to conserve water?

– Covering many plants is a cuticle.

• A waxy, protective layer secreted by cells onto the surface of the plant.

Lab Demonstration• Materials; water, paper towels, wax paper,

paper clips, and string.

• Procedure:1. Wet three paper towel squares.2. Leave one paper towel uncovered.3. Cover one side of another with wax paper.4. Sandwich a third paper towel between two

sheets of wax paper.5. Hang the samples to dry.

– Observe how long it takes each towel to dry.

Lab Demonstration• Class assignment:

–Write in you science notebook (left side)

•How are the paper towels covered with wax paper like plant leaves with cuticles?

• In animals the skeleton provides support.

• What provides support for a plant?

– Cell walls which contain cellulose.– Cellulose molecules form tangled fibers

in plant cell walls providing support.

Classification of Plants• Vascular plants: Have tube-like

structures that carry water, and nutrients throughout the plant.

Classification of Plants• Nonvascular plants: Do not have

tube-like structures and use other ways to move water and substances.

Seedless Plants• Nonvascular plants like moss are only a

few cells thick. Each cell absorbs water directly from it environment.

• Vascular plants distribute water and nutrients to all plant cells.

• Question: Which type of plant can grow larger; nonvascular and vascular?– Vascular can grow bigger and thicker

because the vascular tissue distributes the water and nutrients.

Seedless Plants• Question: Name parts of a plant.

– Roots– Stems– Leaves– Flowers

• Question: What do the flowers produce?– Seeds

Seedless Plants• Question: Do all plants reproduce

from seeds?

• Some plants reproduce by

spores.

Seedless Plants• Question: Can you name a plant

that does not have seeds and uses spores to reproduce?–Mosses

–Ferns– Video: Plants that

– make spores. 2:34

Seedless Plants• Ferns and Mosses:

– We now know that they do not reproduce by seeds but use spores. Therefore they are alike in that way.

– Question: How are they different?• Think vascular, nonvascular

Seedless Plants• Peat and Coal: As seedless plants

died they compacted and compressed and turned into peat. Over time the peat turned into coal.

Seedless Plants• Peat supplies about one third of Ireland’s

energy requirements.• Brain Pop: Seedless Plants

Seed Plants• Most seed plants have leaves, stems,

roots, and vascular tissue.

• They also produce seeds.

• Question: What is inside a seed?– Embryo and stored food. Video: Seeds 2, MSB How a plant

makes seeds 3:02

Gymnosperms• Gymnosperms: Vascular plants that

produce seeds that are not protected by fruit.

• Question: What is an example of this type of plant?– Conifers: Pines, firs, spruces, redwoods.

Angiosperms• Angiosperms: A vascular plant that

flowers and produces fruit with one or more seeds.

• Question: What is an example of an angiosperm?

Angiosperms• Life cycle of angiosperms.

• Question: What do you call a plant that has a life cycle of one year?

Angiosperms• Question: What do you call a plant that

continues to survive for many years?– Perennial– Brain Pop: Seed Plants

Seed Plant Class Work

• Create a list of as many products of seed plants that you can think.– Examples: Potato Chips, oranges.– Video: Sci. of Plants 22