http://www.transformation2013.org/docs/Design%20Challenges/Biology/Plants

Transformation 2013 PBL 5E Planning Form Guide PBL Title: Field Guide for Plants in a Biome Teacher(s): Shane McKay School: East Central High School Subject: Biology Abstract: The students will learn how plants obtain and utilize energy and will be able to identify characteristics of plants and how they have adapted to their environments over time.

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Begin with the End in Mind The theme or “big ideas� for this PBL: Students will be use previous experiences in evolution, ecology, genetics, and classification in order to understand plants. The learner will understand the structure and function of plants and will develop a firm understanding of plant adaptations.

TEKS/SEs that students will learn in the PBL: (4) Science concepts. The student knows that cells are the basic structures of all living things and have specialized parts that perform specific functions, and that viruses are different from cells and have different properties and functions. The student is expected to: (B) investigate and identify cellular processes including homeostasis, permeability, energy production, transportation of molecules, disposal of wastes, function of cellular parts, and synthesis of new molecules.

(5) Science concepts. The student knows how an organism grows and how specialized cells, tissues, and organs develop. The student is expected to: (A) compare cells from different parts of plants and animals including roots, stems, leaves, epithelia, muscles, and bones to show specialization of structure and function.

(8) Science concepts. The student knows applications of taxonomy and can identify its limitations. The student is expected to: (C) identify characteristics of kingdoms including monerans, protists, fungi, plants, and animals.

(10) Science concepts. The student knows that, at all levels of nature, living systems are found within other living systems, each with its own boundary and limits. The student is expected to: (C) analyze and identify characteristics of plant systems and subsystems.

(13) Science concepts. The student knows the significance of plants in the environment.

The student is expected to: (A) evaluate the significance of structural and physiological adaptations of plants to their environments; and (B) survey and identify methods of reproduction, growth, and development of various types of plants.

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Key performance indicators students will develop in this PBL: Students will understand the physiological and structural adaptations of plants to various biomes in the world. The learner will also be able to distinguish specialized parts of plants and how these structures relate to the function of that plant. Furthermore, the student will be able to identify parts of plants and describe the function of each part of a flower, roots, stems, and leaves. Lastly, the learner will have a thorough understanding of the process of photosynthesis and energy production.

21st century skills that students will practice in this PBL: www.21stcenturyskills.org Social and Leadership Skills STEM career connections and real world applications of content learned in this PBL:

Careers: Botanist, Ecologist, Botanical Illustrator, Agriculture Connections: Plants are all around us and without them we would not survive. Students are constantly surrounded by the world of plants and have yet to discover the beauty behind these remarkable organisms. Agriculture plays a vital role in our economy and without these crops our lives would be remarkably different.

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The Problem You and two other partners will assume a role (illustrator, writer, or editor) in the creation of a plant field guide using one of the following biomes: - Rainforest - Tundra - Taiga - Desert - Temperate - Grasslands - Rivers and Streams - Ponds and Lakes - Wetlands - Shoreline - Temperate Oceans - Tropical Oceans Your field guide must include 20 plants from one of the biomes, along with illustrations, scientific name, and an explanation as to the important role each plant plays in that biome (ex. who does it provide nutrients to or is it home for certain organisms, etc.) The field guide will be graded according to organization, ease of read, illustrations, scientific detail, and overall appearance. Great appearance shows great effort!

Roles of each team member: 1. Illustrator – responsible for the drawing of each plant along with labeling the major parts of each plant.

2. Writer – responsible for typing up the field guide and assisting in the research process 3. Editor – primary responsibility is doing the research for the group, gathering the important information and relaying it to the team along with time management.

The editor is also responsible for a professional looking final product.

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Map the PBL Performance Indicators

1. Students will have a working vocabulary of the following terms: roots, stems, leaves, flowers, seeds, cones, moncot, dicot, pistol, stamen, anther, filament, petal, xylem, phloem, stoma, pollen 2. Understand the plants specialized parts and function of these parts 3. The learner will comprehend the physiological and structural adaptations of various plants to the environment 4. Learn the parts of a plant including: roots, stems, leaves, flowers, seeds, and cones 5. The student will understand the process of photosynthesis as it relates to energy production in autotrophes 6. The learner will comprehend the characteristics of Kingdom Plantae 7. Students will also learn the parts of vascular plants including: roots, phloem, xylem, stoma, cuticle, guard cell, stems, and leaves 8. The learner will develop a thorough comprehension behind the reproductive processes of plants

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5E Lesson Plan PBL Title: Field Guide for Plants TEKS/TAKS objectives: TAKS Objective: 2; TEKS: 4B; 5A; 8C; 10C; 13A,B Engage Activity Have student perform the Nature Walk Lab to excite them about the world of plants (see below).

Engage Activity Products and Artifacts Nature Walk Lab Engage Activity Materials/Equipment Dissecting microscope, various types of plants (if you do not have plants around your campus), forceps, rulers, hand lens Engage Activity Resources None Explore Activity Perform the Energy Transfer Lab (see below).

Next, break students up into groups of 3 for the Chromatography Lab (see below). Have students perform lab together.

Maintaining the same groups, introduce the design challenge “Plant Field Guide” and assign roles for each team member.

You and two other partners will assume a role (illustrator, writer, or editor) in the creation of a plant field guide using one of the following biomes: - Rainforest - Tundra - Taiga - Desert - Temperate - Grasslands - Rivers and Streams - Ponds and Lakes

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Wetlands Shoreline Temperate Oceans Tropical Oceans

Your field guide must include 20 plants from one of the biomes, along with illustrations, scientific name, and an explanation as to the important role each plant plays in that biome (ex. who does it provide nutrients to or is it home for certain organisms, etc.) The field guide will be graded according to organization, ease of read, illustrations, scientific detail, and overall appearance. Great appearance shows great effort!

Roles of each team member: 1. Illustrator – responsible for the drawing of each plant along with labeling the major parts of each plant.

2. Writer – responsible for typing up the field guide and assisting in the research process 3. Editor – primary responsibility is doing the research for the group, gathering the important information and relaying it to the team along with time management.

The editor is also responsible for a professional looking final product.

The following website will be of great benefit in the start of your project: http://www.mbgnet.net Hand out scoring rubric for plant field guide.

Complete the team building activity (see NASA Exercise below).

Explore Activity Products and Artifacts Energy Transfer Lab, Chromatography Lab, NASA Exercise Explore Activity Materials/Equipment Safety goggles, Chromatography solvent (92 parts Petroleum ether to 8 parts acetone), Chromatography paper (or filter paper) about 1 cm x 15 cm, Ethyl alcohol, Fresh spinach, Test tubes, Test tube rack, Scissors and Ruler, Fresh leaves of plants, Glass stirring rod, Paper clip, Cork (to fit test tube) ,Mortar and pestle , Sand (optional), 10-ml Graduated cylinder, 25-ml graduated cylinder, coffee filters, acetone, mortar, pestle, hand lens Explore Activity Resources http://www.mbgnet.net

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Explain Activity Break students up into groups and assign them one of the following BrainPop videos and take the quiz at the end of their respective video (be sure to have students e-mail their score to you). Each group will use chart paper and will illustrate their video for the class.

The groups may either list details, draw diagrams, create thinking maps, etc. of their topic (30 minutes). Once all have completed their assignment, they will tape their chart up on the wall. Each team will then do a gallery walk with a docent to learn about each group’s chart. Students should take notes in their journals regarding each chart. Groups should rotate to the next chart every 4 minutes. (A gallery walk with a docent is a technique in which the teacher will re-number the groups. In this case there should be five groups of three students. When you re-number, ask the students to number off one through three.

Regroup the students into three groups of 5. Now there is an expert for each chart. Have the students rotate through the charts and each expert will describe the illustrations presented that represent their specific topic. As the students rotate, have them take notes regarding each chart.) http://www.brainpop.com/science/cellularlifeandgenetics/photosynthesis/ http://www.brainpop.com/science/cellularlifeandgenetics/plantgrowth/ http://www.brainpop.com/science/diversityoflife/seedplants/ http://www.brainpop.com/science/cellularlifeandgenetics/pollination/ http://www.brainpop.com/science/cellularlifeandgenetics/asexualreproduction/ Upon completion of the gallery walk, show the Plant powerpoint presentation and ask students to record notes in their journals.

Explain Activity Products and Artifacts BrainPop Quiz, Chart depicting topic, Gallery Walk notes in journal Explain Activity Materials/Equipment Chart paper, markers, map pencils, computers, tape, LCD Projector, journals, pencils, BrainPop subscription, Internet access Explain Activity Resources http://www.brainpop.com/science/cellularlifeandgenetics/photosynthesis/ http://www.brainpop.com/science/cellularlifeandgenetics/plantgrowth/ http://www.brainpop.com/science/diversityoflife/seedplants/ http://www.brainpop.com/science/cellularlifeandgenetics/pollination/ http://www.brainpop.com/science/cellularlifeandgenetics/asexualreproduction/ Š 2008 Transformation 2013

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Elaborate Activity Students will play the plant part botany game online: http://www.mbgnet.net/bioplants/supermkt.html Pass out Stomata Lab (see below) and have students work in pairs to complete the lab.

Students may go outside the classroom and obtain various leaves or bring some leaves from plants they may have at home.

Elaborate Activity Products and Artifacts Plant part botany game, Leaf Stomata Lab Elaborate Activity Materials/Equipment Microscope slides, microscopes, clear Scotch tape (shiny kind), fast drying clear fingernail polish (non-strengthener), various leaf specimens, computers, Internet access Elaborate Activity Resources http://www.mbgnet.net/bioplants/supermkt.html Evaluate Activity Reintroduce students to the design challenge and put students into Plant Field Guide groups. Assign a biome to each group. Provide materials for students to complete their project. Provide students with a copy of the rubric.

Students will share their finished products with the class upon completion.

Evaluate Activity Products and Artifacts Plant Field Guide, Presentation Evaluate Activity Materials/Equipment Computers, textbooks, printer, computer paper, map pencils, notebooks to bind field guides Evaluate Activity Resources http://www.mbgnet.net

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Plan the Assessment Engage Artifact(s)/Product(s): Nature Walk Lab

Explore Artifact(s)/Product(s): Energy Transfer Lab, Chromatography Lab

Explain Artifact(s)/Product(s): Brainpop Gallery Walk,

Elaborate Artifact(s)/Product(s): Plant part Botany Game, Viewing Plant Stomata Lab

Evaluate Artifact(s)/Product(s): Plant Field Guide

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Rubric Field Guide to Plants Rubric

Biome: _______________________________________________________ Teacher Name:

Student Name: ________________________________________ CATEGORY Creativity

25 Lots of creative energy used to present a unique plant field guide

20 Some creative energy used to present a unique plant field guide

15 Little creativity used in project.

10 No creativity used in project.

Construction - Care Taken

Great care taken in construction process so that the structure is neat, attractive and follows plans accurately.

Constuction was careful and accurate for the most part, but 1-2 details could have been refined for a more attractive product.

Construction accurately followed the plans, but 3-4 details could have been refined for a more attractive product.

Construction appears careless or haphazard. Many details need refinement for a strong or attractive product.

Scientific Knowledge

Explanations indicate a clear and accurate understanding of scientific principles underlying the construction and modifications.

Explanations indicate a relatively accurate understanding of scientific principles underlying the construction and modifications.

Explanations indicate a somewhat accurate understanding of scientific principles underlying the construction and modifications.

Explanations do not illustrate much understanding of scientific principles underlying the construction and modifications.

Plant Field Guide Elements Field Guide had all 20 plants Field Guide contained 16 with illustrations and 19 plants, or was lacking explainations detailed illustrations, and explainations

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Field Guide had only 11 - 15 Field guide had 10 or fewer plants, lacked detailed plants, or severly lacked illustrations, or illustrations or explainations explainations

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Story Board 

Day 1 Engage: Nature walk and lab (90 min)

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Day 2 Explore: Energy transfer lab (30 min) Chromatography lab (60 min.)

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 Week 1 Activities 

 Week 2 Activities

Day 6 Plant Field Guide Design Project (90 min.)

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Day 7 Plant Field Guide Design Project (90 min.)

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Day 3 Introduce design project and break students up into groups Assign roles for each group (45 min) Team Building NASA© Survival Game (45 min) Day 8 Plant Field Guide Design Project (90 min.)

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Day 4 Explain: Brainpop video Gallery Walk (60 min) Plants ppt (30 min)

Day 9 Plant Field Guide Due at end of class (90 min.)

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Day 5 Elaborate: Plant part Botany Game (15 min.)

Stomata labs (45 min) Evaluate: Assign biomes to each group and allow them time to do research on the computers (30 min.)

Day 10 Presentations (90 min.)

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NATURE WALK PLANT LAB Objective: Students will be able to compare and contrast the structures of three different types of plants.

Materials: Dissecting Microscope or hand lens Metric ruler Various types of plants (if you do not have plants around your campus) - Mosses, ferns, flowers, geraniums, etc.

Procedure: 1. Walk around the outside of your campus searching for various types of plants. Remove a leaf or part of plant from each different type of plant that you discover (required obtaining 3 different types of plants or leaves).

Caution: be careful what you pick, ask your teacher for permission if you do not know what type of plant it is. Some plants are very caustic to the skin and cause redness, itching, and burning 2. Return to the lab and obtain the rest of your materials that you will need to complete the lab.

3. Observe your plants and make notes about its characteristics in the table. Identify any parts of the plant that you can recognize.

4. Measure various aspects of your leaf or plant and record your data in the table.

5. Observe your plant parts under a dissecting microscope, draw and color what you see.

Record your observations you notice.

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Characteristics

Identifiable Parts

Various Measurements

Drawing of Plant / Leaf

Observations

Questions: 1. How are the three plants alike?

2. How do they differ?

3. What are the major parts of each plant and what are their functions?

4. Try to create a classification system for the three plants you recovered. Explain your reasons for classifying them into these groups.

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Energy Transfer in Photosynthesis and Chlorophyll Fluorescents INTRODUCTION When a pigment absorbs light, electrons of certain atoms in the pigment molecules are boosted to a higher energy level. The energy of an absorbed photon is converted to the potential energy of the electron that has been raised to an excited state. In most pigments, the excited electron drops back to its ground-state, or normal orbit, and releases the excess energy as heat. Some pigments, including chlorophyll, emit light as well as heat after absorbing photons.

In the chloroplast, these excited electrons jump from the chlorophyll molecule to a protein molecule in the thylakoid membrane, and are replaced by electrons from the splitting of water. The energy thus transferred, is used in carbohydrate production.

This release of light is called fluorescence. Chlorophyll will fluoresce in the red part of the spectrum, and also give off heat. In this lab, you will observe this fluorescence by separating the chlorophyll from the thylakoid membrane.

MATERIALS Spinach leaves, Mortar and pestle, Flashlight or small lab light, Test tube, Filter paper, Acetone, Funnel, 25-mL graduated cylinder, Ring stand or funnel rack, Safety goggles PROCEDURE 1. Grind the spinach leaves using a mortar and pestle.

2. Add acetone to the ground leaves, using enough acetone and spinach leaves to get between 10 and 15 mL of extract.

3. Set up your filtering apparatus, and using proper filtering technique, filter the extract to a test tube. NOTE: Use a small amount of acetone to wet the filter paper, to hold it into place, instead of water.

4. Shine a flashlight, or other similar light source, through the test tube and extract.

5. Observe the fluorescence of the chlorophyll at a 90 degree angle to the flashlight.

QUESTIONS 1. Describe what colors do you see? Why?

2. Why do spinach leaves contain chlorophyll?

3. Why are some leaves green and other red, yellow, or orange?

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4. What important function do leaves perform for the plant?

5. How do you think the energy that is created by the chloroplasts gets to the rest of the plant?

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Chromatography Lab INTRODUCTION: Chlorophyll often hides the other pigments present in leaves. In Autumn, chlorophyll breaks down, allowing xanthophyll and carotene, and newly made anthocyanin, to show their colors.

The mix of pigments in a leaf may be separated into bands of color by the technique of paper chromatography. Chromatography involves the separation of mixtures into individual components. Chromatography means "color writing." With this technique the components of a mixture in a liquid medium are separated. The separation takes place by absorption and capillarity. The paper holds the substances by absorption; capillarity pulls the substances up the paper at different rates. Pigments are separated on the paper and show up as colored streaks. The pattern of separated components on the paper is called a chromatogram.

PRELAB PREPARATION: Gather leaves from several different plants. CAUTION: Avoid poisonous plants. Autumn leaves from deciduous trees are especially interesting. Sort the leaves by kind (maple, etc.) and color.

Review a diagram of a plant cell. Find the grana and the chloroplasts of the cell.

MATERIALS: Safety goggles Chromatography solvent (92 parts Petroleum ether to 8 parts acetone) Chromatography paper (or filter paper) about 1 cm x 15 cm Ethyl alcohol Fresh spinach Test tube Test tube rack Scissors and Ruler Fresh leaves of plants Glass stirring rod Paper clip Cork (to fit test tube) Mortar and pestle Sand (optional) 10-ml Graduated cylinder PROCEDURE: Leaves should be grouped by kind (maple, etc.) and color. Work with a spinach leaf and with one or more other types. CAUTION: Chromatography solvents are flammable and toxic. Have no open flames; maintain good ventilation; avoid inhaling fumes.

1. Cut a strip of filter paper or chromatography paper so that it just fits inside a 15-cm (or larger) test tube. Cut a point at one end. Draw a faint pencil line as shown in figure 1. Bend a paper clip and attach it to a cork stopper. Attach the paper strip so that it hangs inside the tube, as shown.

The sides of the strip should not touch the glass.

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2. Tear a spinach leaf into pieces about the size of a postage stamp. Put them into a mortar along with a pinch or two of sand to help with grinding. Add about 5 ml ethyl alcohol to the leaf pieces. Crush leaves with the pestle, using a circular motion, until the mixture is finely ground.

The liquid in which the leaf pigments are now for paper chromatography dissolved is called the pigment extract.

3. Use a glass rod to touch a drop of the pigment extract to the center of the pencil line on the paper strip. Let it dry. Repeat as many as 20 times, to build up the pigment spot. NOTE: You must let the dot dry after each drop is added. The drying keeps the pigment dot from spreading out too much.

4. Pour 5 ml chromatography solvent into the test tube. Fit the paper and cork assembly inside.

Adjust it so that the paper point just touches the solvent (but not the sides of the tube). The pigment dot must be above the level of the solvent. Watch the solvent rise up the paper, carrying and separating the pigments as it goes. At the instant the solvent reaches the top, remove the paper and let it dry. Observe the bands of pigment. The order, from the top, should be carotenes (orange), xanthophylls (yellow), chlorophyll a (yellow-green), chlorophyll b (blue-green), and anthocyanin (red). Identify and label the pigment bands on the dry strip. Write the species of leaf on the strip as well.

Record the species, external color, and chromatogram pigments in the DATA TABLE of your report sheet.

5. Each pigment has an Rf value, the speed at which it moves over the paper compared with the speed of the solvent.

Rf = Distance moved by the pigment / Distance moved by the solvent Measure the distance in cm from the starting point (pencil line) to the center of each pigment band. Then measure the entire distance traveled by the solvent. Remember, the starting point for the solvent is also the pencil line and the ending point for the solvent is the top edge of the paper.

Do the required divisions and record your Rf values in the DATA TABLE of your report sheet.

6. Wash the mortar and pestle thoroughly, using a little alcohol to remove any remaining pigment.

7. Repeat steps 1 through 6 for each species.

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Chromatography Data Chromatogram Pigments Colors from Pigment top names Rf values Leaf (Species)

External Color

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NASA Exercise: Survival on the Moon Scenario: You are a member of a space crew originally scheduled to rendezvous with a mother ship on the lighted surface of the moon. However, due to mechanical difficulties, your ship was forced to land at a spot some 200 miles from the rendezvous point. During reentry and landing, much of the equipment aboard was damaged and, since survival depends on reaching the mother ship, the most critical items available must be chosen for the 200-mile trip. Below are listed the 15 items left intact and undamaged after landing. Your task is to rank order them in terms of their importance for your crew in allowing them to reach the rendezvous point. Place the number 1 by the most important item, the number 2 by the second most important, and so on through number 15 for the least important.

Your Ranking NASA Ranking _______ Box of matches _______ _______ Food concentrate _______ _______ 50 feet of nylon rope _______ _______ Parachute silk _______ _______ Portable heating unit _______ _______ Two .45 caliber pistols _______ _______ One case of dehydrated milk _______ _______ Two 100 lb. tanks of oxygen _______ _______ Stellar map _______ _______ Self-inflating life raft _______ _______ Magnetic compass _______ _______ 5 gallons of water _______ _______ Signal flares _______ _______ First aid kit, including injection needle _______ _______ Solar-powered FM receiver-transmitter _______

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Answers to the Survival on the Moon Exercise Item

NASA Ranking

NASA's Reasoning

Box of matches

15

Virtually worthless -- there's no oxygen on the moon to sustain combustion

Food concentrate

4

Efficient means of supplying energy requirements

50 feet of nylon rope

6

Useful in scaling cliffs and tying injured together

Parachute silk

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Protection from the sun's rays

Portable heating unit

13

Not needed unless on the dark side

Two .45 caliber pistols

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Possible means of self-propulsion

One case of dehydrated milk

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Bulkier duplication of food concentrate

Two 100 lb. tanks of oxygen

1

Most pressing survival need (weight is not a factor since gravity is one-sixth of the Earth's -- each tank would weigh only about 17 lbs. on the moon)

Stellar map

3

Primary means of navigation - star patterns appear essentially identical on the moon as on Earth

Self-inflating life raft

9

CO2 bottle in military raft may be used for propulsion

Magnetic compass

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navigation 5 gallons of water

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Needed for replacement of tremendous liquid loss on the light side

Signal flares

10

Use as distress signal when the mother ship is sighted

First aid kit, including injection needle

7

Needles connected to vials of vitamins, medicines, etc. will fit special aperture in NASA space suit

Solar-powered FM receiver-transmitter

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For communication with mother ship (but FM requires line-of-sight transmission and can only be used over short ranges)

Scoring: For each item, mark the number of points that your score differs from the NASA ranking, then add up all the points. Disregard plus or minus differences. The lower the total, the better your score.

0 - 25 excellent 26 - 32 good 33 - 45 average 46 - 55 fair 56 - 70 poor -- suggests use of Earth-bound logic 71 - 112 very poor – you’re one of the casualties of the space program!

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Viewing Plant Stomata -1 The epidermis of a leaf has microscopic openings called stomata. Stomata allow the exchange of gases between the plant and the outside environment. The rate of gas diffusion is regulated by two guard cells. As water enters the guard cells, their shapes change thus opening the stoma. When the stomata are open, diffusion rates of carbon dioxide, water vapor, and oxygen are greater. Therefore when water leaves, the guard cells relax, the stoma closes, and diffusion rates are reduced. The closing of the stomata help the plant by preventing dehydration due to loss of water vapor. Generally stomata are open during the day and close at night.

Functioning of the stomata could be affected by light intensity, stress (disease, insects, etc.), climate, and/or latitude.

The focus of this lab is to learn how to prepare a cast of leaf stomata. After mastering this technique, students will be able to explore stomatal distribution and possibly stomatal opening and closing in response to various factors. Possible investigations could include: 1. stomatal distribution: top vs. bottom 2. stomatal distribution: various plant species 3. stomatal opening: various times of day 4. stomatal opening: various leaf positions on the tree Objectives: To learn a technique for convenient microscopic study of leaf surfaces.

Materials: Microscope slides Microscope Clear Scotch tape (shiny kind) Fast Drying Clear fingernail polish (not strengthener) Various leaf specimens (purchase or go out and pick some yourself)

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Safety Notes: Avoid using plants which may cause skin irritations.

Procedure: 1. Select leaf. Be sure it is dry. To prepare cast of leaf surface, paint small area of leaf surface with nail polish. Allow the area to dry completely. No longer than 15 minutes because polish, which remains on the surface longer, will be difficult to remove.

2. Cut a piece of Scotch tape approximately 3.0 cm in length. Fold a small portion of the tape over onto itself to use as a ‘handle’. Once the polish is dry, place the sticky surface on the nail polish cast and press gently. Using the ‘handle’, carefully pull the nail polish cast from the leaf surface.

3. Place the cast on a clean microscope slide. Press gently. The adhesive on the tape should mount the cast onto the slide.

4. Examine the slide under high power to view stomata.

Viewing Plant Stomata Evaluation: 1. Sketch your cast.

2. Why does the leaf need to be dry for the procedure? (Think!)

3. What problem would leaf hairs present? How could this be reduced?

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Viewing Plant Stomata - 2 Possible Application: Determining which leaf surface has stomata 1. Select two leaves.

2. Label one microscope slide adaxial (top surface) and another abaxial (bottom surface).Prepare two casts as described in the Procedure for Viewing Plant Stomata – 1; one of the adaxial surface and one of the abaxial surface.

3. Examine the slides under high power to view stomata.

Viewing Plant Stomata - 2 Evaluation:

Name_________________________

1. Sketch your casts. Be sure to label which is which.

2. Which surface of the leaf has more stomatal pores? Why?

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