PLANTSPlants We Eat...the entire food web. Most of the meat and dairy products we eat were produced...

RESOURCES.SCIENCEWORLD.CAThis resource was created with support from BC Agriculture in the Classroom Foundation | aitc.ca/bc

PLANTSPlants We Eat

A CLOSER LOOK AT THE PLANTS WE EAT AND HOW THEY GROW

INTRODUCTION

Plants play an important role in our diet. Not only are they a healthy part of our meals, providing nutrients, vitamins, minerals, fibre and water, but they are also the base of the entire food web. Most of the meat and dairy products we eat were produced by farm animals that were fed plants. That means that even when you are eating meat, you are indirectly eating vegetables.

These activities will get students looking more closely at plants by identifying plant parts, learning about how plants grow and reproduce, designing their own seeds, and even growing their own plants.

BACKGROUND

Plants play a big part of keeping us healthy. Canada’s Food Guide recommends that we eat several different kinds of fruits and vegetables five times a day so that we get a variety of vitamins and minerals.

FOOD RAINBOWNo one food or food group provides all the nutrients our bodies need, so eating a variety of foods is important. Brightly coloured fruits and vegetables generally have more nutrients, and eating at least one fruit or vegetable from each colour group (red, orange/yellow, green, blue/purple and white) gives our bodies the range of healthy vitamins, minerals and phytochemicals that make and keep our bodies healthy.

PLANT PARTSWe get energy from plants in two ways: by eating the seeds or eating parts of the mature plant. Most plants have roots, stems, leaves, flowers, fruits and seeds. These plant parts all have a role in keeping a mature plant healthy and helping it reproduce.

OBJECTIVES:Students will be able to:• Identify and compare healthy

variety of fruits and vegetables and how they can improve their own eating habits.

• Identify and compare parts of plants that we eat and the roles that they play in a mature plant.

• Explain the needs of plants by observing the effect of capillary action.

• Explain how plants use seeds to reproduce, and how seeds are dispersed.

• Identify plants’ adaptations to their environment.

CURRICULUM CONNECTIONS BY GRADE:K. Characteristics of Living ThingsK. Processes and Skills of Science (Observing)1. Life Sciences (Needs of Living Things)1. Processes and Skills of Science (Communicating & Classifying)3. Life Sciences (Plant Growth and Changes)3. Health and Career Education4. Health and Career Education5. Health and Career Education6. Life Sciences (Diversity of Life)

LIST OF ACTIVITIES:

• Eating the Rainbow

• Plant Relay

• Get to Know a Plant

• Grow Tag

• Capillary Action

• Seed Dissection

• Brain Sprouts

• Biodegradable Seedling Pots


PLANTSPlants We Eat

Roots help provide support by anchoring the plant and absorbing water and nutrients needed for growth. Roots can also store sugars and carbohydrates that the plant uses to carry out other functions. Plants can have a taproot system, like a carrot, or a fibrous root system, like a lettuce.

Stems carry water and nutrients from the roots to the leaves, and carry the food produced by the leaves to other parts of the plant. These require two types of tubes made up of different kinds of cells: xylem cells move water and phloem cells move food. Stems also provide support for the plant and can move the leaves toward the sunlight needed to produce food. Most plants can be divided into one of two general categories: herbaceous (short, soft plants) or woody (tall, stiff plants), depending on the kind of stem.

Leaves come in many different shapes and sizes, but their job is to make food for the rest of the plant.

Flowers help the plant reproduce so that more plants can be made.

Fruit can be thought of as a swollen flower. Apples, oranges, even tomatoes, cucumbers and beans are types of fruit because they have seeds inside them. Fruit is meant to be eaten so that its seeds are dispersed by the animal that eats it (seeds also tend to get left behind along with material that will help them grow into new plants).

Seeds contain everything needed to become a mature plant: a tiny plant (embryo) with leaves, stems, root parts and the food it needs to begin growing. This is all wrapped up in a seed coat, which protects everything from microbes and other invaders, and prevents the insides from drying out.

FLOWERS

LEAVES

ROOTS

SEEDS

FRUITS

STEMS


PLANTSPlants We Eat

HOW PLANTS GROWSeeds are the beginning of the plant life cycle. After the seed is dispersed, it gets buried in the ground. It takes in water and nutrients from the soil to germinate. The seed grows small roots and shoots that push through the surface of the soil.

Once the shoot has used up all the energy in the seed, it begins to produce its own energy from sunlight, water and carbon dioxide (photosynthesis) and develops to become a seedling. Seedlings and mature plants take in water and dissolved nutrients through a process called capillary action. Water is drawn up through millions of tiny tubes called xylem, and deposits nutrients in various parts of the plant. In the leaves, the plant uses energy from the sun, carbon dioxide from the air, and water to produce sugars that help the plant to develop all of its parts, including seeds that begin the cycle again.


PLANTSPlants We Eat

VOCABULARY

Capillary action: The ability of an object to draw a liquid into it (also called wicking)

Germinate: The sprouting of a seedling from a seed

Plant embryo: A baby plant, contained in a seed, waiting for the right conditions to make it grow

Seed coat: Protective layer on the outside of the seed

Phytochemicals: Literally, “plant chemicals”, these are compounds found in plants that, while they aren’t essential nutrients like fats, proteins and carbohydrates, are thought to be beneficial to our health

Surface tension: Water’s tendency to be attracted to itself and away from other materials. Caused by hydrogen bonding

Transpiration: A process similar to evaporation that is part of the water cycle. The loss of water vapour from parts of plants (similar to sweating), especially in leaves

Xylem: Long, “woody” tubes in a plant stem that transport water from the roots to the leaves

REFERENCES

» North Dakota State University | Julie Garden-Robinson, PhD, LRD | What Color is Your Food? Taste a rainbow of fruits and vegetables for better health http://www.ag.ndsu.edu/pubs/yf/foods/fn595w.htm» Wikipedia | Phytochemical http://en.wikipedia.org/wiki/Phytochemical» Oklahoma State University | Plant Parts We Eat http://oklahoma4h.okstate.edu/aitc/lessons/primary/parts.pdf» Sierra Club of BC | Going Wild! Teaching about Wild Products from BC’s Coastal Rainforests http://goo.gl/Lvwy4» University of Florida Chemistry Outreach Program | Capillary Action In Plants http://www.chem.ufl.edu/~saacs/outreach/capillary.pdf» JVC’s Science Fair Projects | Capillary Action and Transpiration http://scienceprojectideasforkids.com/2010/capillary-action-transpiration/» Biology4kids.com | Plants Vascular Systems http://www.biology4kids.com/files/plants_xylemphloem.html» BC Agriculture in the Classroom Foundation | Beans and their Buddies http://www.pacificedgepublishing.com/cgi-bin/ccp51/cp-app.cgi?pg=product_science» Project Gutenberg | W.J. Beal, MS, PhD | Seed Dispersal http://www.gutenberg.org/files/26158/26158-h/26158-h.htm» Province of BC | Provincial Health Officer’s Annual Report 2005 | Food, Health and Well-Being http://www.health.gov.bc.ca/pho/pdf/phoannual2005.pdf» Washington State University | Gardening in Western Washington | Seed Germination http://gardening.wsu.edu/library/vege004/vege004.htm


PLANTSPlants We Eat

OTHER RESOURCES » BC Agriculture in the Classroom Foundation http://www.aitc.ca/bc/» UBC | UBC Farm | Children’s Learning Garden http://ubcfarm.ubc.ca/teaching-learning/childrens-learning-garden» BBC | The Private Life of Plants http://www.bbc.co.uk/programmes/p00fgpfl/clips


PLANTSPlants We Eat

ACTIVITY 1: EAT A RAINBOW - 15 mins

By creating a class rainbow that represents what students eat in the course of a day, students identify whether they can improve the variety of fruits and vegetables they choose.

Canada’s food guide suggests that we “eat at least one dark green and one orange vegetable each day,” but it’s more fun—and more nutritious—to “eat a rainbow”! Eating a rainbow every day means eating at least one fruit or vegetable from each of the colour groups: red, orange/yellow, green, blue and white.

Phytochemicals (literally “plant chemicals”) give fruits and vegetables their colour, taste and smell, and also may affect the severity of diseases such as cancer, stroke or metabolic syndrome. By eating the rainbow, we give our bodies the range of healthy vitamins, minerals and phytochemicals that make and keep our bodies healthy. Sure, you can take some of them as dietary supplements, but some scientists think that you get the best health benefits if you eat the whole food instead. (Plus, it’s more filling.)

WHAT TO DO

1. Brainstorm/review reasons people need to eat a variety of different coloured vegetables and fruits, and predict whether the class as a whole is eating a healthy balance of plants.

2. Write down a list of all of the meals and snacks you ate yesterday, and identify all of the fruits and vegetables. Remember:

• Fruit and vegetables are: fresh, frozen, canned and dried fruit and vegetables, and real fruit juice.

• Fruit and vegetables are not: fruit-flavoured juices and highly processed foods like fruit candies and potato chips.

3. Write out the name of each type of fruit or vegetable that you ate yesterday on an individual slip of paper.

ACTIVITY

MATERIALS:

• Food Rainbow handout

• paper

• pencils

• slips or squares of paper— at least 5 per student

• markers or colouring pencils in red, orange, yellow, green, blue and black (to outline white)

• masking tape

• whiteboard, bulletin board or large wall space


PLANTSPlants We Eat

4. Colour-code each slip of paper by using a coloured marker. Use the Food Rainbow handout to help identify some tricky ones, especially foods with peels.

Hint: Think about which part you eat. For example, bananas are a “white” fruit because the part you eat (and the part with nutrients) is white, but apples are red, green or yellow, depending on the colour of their skin.

5. Put masking tape on the back of each slip of paper, and arrange the slips on a wall, whiteboard or bulletin board to create a rainbow of all of the fruits and vegetables the class ate in one day.

KEY QUESTIONS

» What types of plants do you eat every day? What types of plants are a part of the cooked meals you eat?

» What plants do you eat sometimes? What do you never eat?» Are you eating at least five fruits or vegetables in a day?» What colour are the plants that you eat? Are you eating plants from each colour group?» What colour of fruit and vegetables do you think you could eat more often?» Is your class eating enough plants from every colour category? If not, what kinds of foods

should everyone try to eat more often?

EXTENSIONS

» Make individual rainbows several times over a week or month, and identify which fruits and vegetables you eat frequently and which you could encourage your family to eat more often.

» Does your school eat a rainbow? Try this activity with the whole school to create a huge fruit and vegetable rainbow. What fruits and vegetables could everyone try eating more often?

» Start a campaign to get your class or school eating more healthily. Can you find a local supermarket or farm who can donate some items for you to try?

NOTES

CO

LO

UR

RE

DO

RA

NG

E/Y

EL

LO

WG

RE

EN

BL

UE

/PU

RP

LE

WH

ITE

WH

Y

EA

T

TH

EM

?

Lyco

pene

s »

may

redu

ce th

e ris

k of

can

cer

Anth

ocya

nins

»

prot

ect c

ells

from

dam

age

» go

od fo

r hea

rt h

ealt

h

Caro

teno

ids*

»

redu

ce ri

sk o

f can

cer &

hear

t dis

ease

»

impr

ove

your

imm

une

syst

em

» m

aint

ain

heal

thy

muc

ous

mem

bran

es a

nd e

yes

Lute

in

» ke

eps

eyes

hea

lthy

Indo

les

» m

ay p

rote

ct a

gain

st

som

e ca

ncer

s

Anth

ocya

nins

»

prot

ect c

ells

from

dam

age

» m

ay re

duce

risk

of c

ance

r,

st

roke

& h

eart

dis

ease

» m

ay im

prov

e m

emor

y

Anth

oxan

thin

s»

low

er c

hole

ster

ol a

nd

bl

ood

pres

sure

» m

ay re

duce

som

e ca

ncer

s

an

d he

art d

isea

se

FO

OD

S»

Red

appl

es

» B

eets

» Re

d ca

bbag

e

» Ch

erri

es

» Cr

anbe

rrie

s

» Pi

nk g

rape

frui

t

» Re

d gr

apes

» Re

d pe

pper

s

» Po

meg

rana

tes

» Re

d po

tato

es

» Ra

dish

es

» Ra

spbe

rrie

s

» Rh

ubar

b

» St

raw

berr

ies

» To

mat

oes

» W

ater

mel

on

Yello

w»

Yello

w a

pple

s

» Le

mon

s

» Ye

llow

pep

pers

» Pe

ars

» Co

rn

» Pi

neap

ple

» Ye

llow

bea

ns

Ora

nge

» Ap

rico

ts

» B

utte

rnut

squ

ash

» Ca

ntal

oupe

» Ca

rrot

s

» G

rape

frui

t

» M

ango

es

» N

ecta

rine

s

» O

rang

es

» Pa

paya

s

» Pe

ache

s

» Pu

mpk

in

» Sw

eet p

otat

oes

» G

reen

app

les

» Ar

ticho

kes

» As

para

gus

» Av

ocad

os

» G

reen

bea

ns

» B

rocc

oli

» B

russ

els

spro

uts

» G

reen

cab

bage

» Cu

cum

bers

» G

reen

gra

pes

» H

oney

dew

mel

on

» Ka

le

» Ki

wi

» Le

ttuc

e

» Li

mes

» G

reen

oni

ons

» Pe

as

» G

reen

pep

per

» Sp

inac

h

» Zu

cchi

ni

» B

lack

berr

ies

» B

lueb

erri

es

» Eg

gpla

nt

» Fi

gs

» Pl

ums

» Pr

unes

» Pu

rple

gra

pes

» Ra

isin

s

» B

anan

as

» Ca

ulifl

ower

» G

arlic

» G

inge

r

» M

ushr

oom

s

» O

nion

s

» Pa

rsni

ps

» Po

tato

es

» Tu

rnip

s

FO

OD

RA

INB

OW

Eat

at

least

on

e f

ruit

or

veg

eta

ble

fro

m e

ach

co

lou

r g

rou

p t

o g

et

a f

ull

co

mp

lem

en

t o

f vit

am

ins,

nu

trie

nts

an

d p

hyto

ch

em

icals

,—an

d h

elp

keep

us

healt

hy!

*No

te: C

itru

s fr

uit

s lik

e o

ran

ges

are

n’t

a s

ou

rce o

f V

itam

in A

(p

rod

uced

by c

aro

ten

oid

s) b

ut

they a

re a

go

od

so

urc

e o

f vit

am

in C

an

d f

ola

te (

a B

vit

am

in)

PLANTSPlants We Eat


GAME

MATERIALS:

• 1 bag of fruit and vegetables for each group of students

• 5–8 buckets or bins

• labels for plant parts

ACTIVITY 2: PLANT RELAY - 30 mins

In this activity, students discover which parts of different plants people eat by playing a classification game.

Which parts of the plant do we usually eat? It pays to know, because some of the plants we eat are poisonous—but only if we eat the wrong part. Tomatoes are delicious, but the leaves of a tomato plant are poisonous, so for a long time, people were afraid to eat tomatoes! The leaf blade of rhubarb is also toxic and can be fatal if eaten, yet we can eat the delicious petiole (the stalk). Elderberries are delicious, but their stems can cause nausea and stomach upset, and every part of a cherry tree is poisonous, except for the ripe fruit.

And with some plants, we eat more than one part. The root of the beet plant is what most people like to eat, but the leaves are good to eat, too. With peas and beans, the pod is the entire fruit and individual peas and beans are seeds.

Whether they are delicious or poisonous, all parts of a plant play a role in keeping the plant alive and healthy.

WHAT TO DO

Preparation

1. Photocopy (double-sided) and cut out the labels for plant parts. You may choose to introduce some, but not all plant-part categories. Stick each label to a bucket or bin.

2. Make up a fruit and vegetable bag for each group of 5–6 students. Each bag should contain at least one plant part from each of the categories (e.g., 1 tuber, 1 stem, 1 leaf, etc.), and all bags should contain the same total number of items.

3. Create the relay space: mark a start line at one end of the room and a finish line at the other end. Line up a labelled bin for each plant part category.

SEEDS STEMS LEAVES BULBS TUBERS PETIOLES ROOTS FRUITS


PLANTSPlants We Eat

Game

1. Divide the class into teams of five or six, and have them line up behind the start line.

2. Place the fruit and vegetable bags midway between the start line and the bins.

3. The first student in each line runs to grab an item from their team’s bag and races to put it into the appropriate bin. Students can get help from their teammates.

4. These students return to the start line to tag the next student on their team.

5. The relay continues until all the plant parts have been sorted into bins.

To keep track of points

1. Stand by the bins and write down their points as they put them in the correct bin.

2. The team that finished first gets two extra points.

3. Deduct points if they throw the items into the bins (you might need to make the plants survive for more than one lesson) and for any unsportsmanlike behaviour.

Discussion

1. Review the contents of the bins with the students and discuss the placement of any confusing items.

2. Have students taste the fruit and vegetables (or make a salad or stew).

KEY QUESTIONS

» Are the fruit and vegetables we eat a part or a whole plant?» What does each part do for the plant?» Why are stems longer in some plants? » Do we eat more than one part of some plants?

EXTENSIONS

» Visit a produce store and identify the plant parts that you see. » Create silly fantasy plants by combining plant parts to make one whole, functional plant.

For example, broccoli flowers with celery stems, spinach leaves with beet roots. Stick them together with toothpicks or twist ties. Snack on your creations!

NOTES

ROOTS

BULBS

CARROT (THE ORANGE PART)

ONION

HOLD THE PLANT IN THE GROUND, ESPECIALLY WHEN IT IS WINDY. THEY ALSO SOAK UP WATER AND NUTRIENTS FOR THE PLANT.

EXAMPLES: CARROTS, TURNIPS, RADISHES

UNDERGROUND STEMS THAT STORE LOTS OF FOOD IN THEIR LEAVES.

EXAMPLES: LEEK, ONIONS, GARLIC

TUBERS

LEAVESLETTUCE

POTATO

UNDERGROUND STEMS THAT ARE SWOLLEN WITH STORED NUTRIENTS.

EXAMPLES: POTATOES, SWEET POTATOES

CATCH THE SUNLIGHT AND MAKE FOOD FOR THE PLANT. LEAVES ALSO LET WATER AND GASES SUCH AS OXYGEN AND CARBON DIOXIDE IN AND OUT OF THE PLANT.

EXAMPLES: LETTUCE, CABBAGE, SPINACH

FRUITS

SEEDS

TOMATO

SUNFLOWER SEED

MADE BY THE FLOWER PARTS AND HAVE SEEDS INSIDE THEM.

EXAMPLES: TOMATOES, CUCUMBERS, ZUCCHINIS, ORANGES, APPLES, GRAPES, STRING BEANS

STORE FOOD INSIDE FOR THE PLANT EMBRYO AND GROW INTO MATURE PLANTS.

EXAMPLES: SUNFLOWER SEEDS, COCONUTS (ONE OF THE WORLD’S BIGGEST SEEDS), SESAME SEEDS, POPPY SEEDS, COFFEE BEANS, LIMA BEANS

STEMS

PETIOLESRHUBARB

ASPARAGUS

HELP PLANTS STAND UP AND MOVE FOOD AND WATER TO ALL OF THE OTHER PARTS.

EXAMPLE: ASPARAGUS

SPECIAL STEMS THAT HOLD THE LEAVES.

EXAMPLES: CELERY, RHUBARB


PLANTSPlants We Eat

ACTIVITY

MATERIALS:

Per group

• 1 small potted edible plant (e.g., tomatoes, strawberries, peppers)

Per student

• 1 blank piece of paper

• pencil and eraser

ACTIVITY 3: GET TO KNOW A PLANT! - 30–60 mins

A good way to understand the way something works is to draw it. In this activity, students use several senses to observe a plant. They then use these observations to form a descriptive drawing.

This activity was adapted from Going Wild! Teaching about Wild Products from BC’s Coastal Rainforests | http://goo.gl/Lvwy4.

WHAT TO DO1. At the top of the blank piece of paper, write the name of the plant e.g. tomato.

2. Carefully observe and then draw the plant. What does the top of the plant look like? The middle? The bottom? What do the roots look like?

3. Now take a closer look. Draw an individual branch. What shape are the leaves? How are they arranged on the stem? Are there cones, fruits or flowers?

4. Close your eyes and feel the plant. What does it feel like? Under your drawing or on another piece of paper, write some words that describe the texture (e.g., rough, dry, soft).

5. Smell the plant. How does it smell? Write some words that describe the smell.

KEY QUESTIONS» What features stand out when you look at the whole plant (e.g., shape, colour)?» What features stand out when you look at parts of it up close? » What part of this plant do we eat?

EXTENSIONS

» Label the parts of the plant. » Instead of all students drawing the same plant, go out into a garden and ask students to

choose different plants. » Ask students to research the habitat and specific needs of their plants. » Dissect a cut flower, or another part of a plant.


PLANTSPlants We Eat

GAME

MATERIALS:

• Bandanas or pinnies in four colours

• A large, open space (gym or field)

ACTIVITY 4: GROWING TAG - 20 mins

Students play a variation of chain tag that demonstrates that a plant needs water, carbon dioxide and sunlight to grow.

Unlike animals, plants make their own food, using a process called photosynthesis. But to do it, they need a few things: water, carbon dioxide, and sunlight. Using special parts on their leaves, they absorb carbon dioxide and sunlight (during the day), and using their roots and a process called capillary action, they absorb water.

During photosynthesis, the plant uses energy from sunlight to take the hydrogen from a water molecule and add the carbon dioxide, to produce a sugar (also called a carbohydrate). Plants use these sugars to grow and produce structures like more roots, stems, leaves and fruit that we eat.

WHAT TO DO

1. Select four students to be Plants.

2. Split the remaining students into three groups: Sunlight, Water and CO2. Identify each group with a colour of bandana or pinny.

3. Everyone spreads out around the game space. Sunlight, Water and CO2 cannot move until they are tagged, but Plants can move around.

4. Plants are “it,” and race to tag, in this order: A. Sunlight, B. Water and C. CO2, who link arms with the end of the chain and move around with the plant.

5. After creating a chain of four, they are a larger plant, and can begin again at Sunlight, then Water, then CO2, to grow even larger.

6. The biggest Plant (chain with the most students) wins.

KEY QUESTIONS

» What molecules does a plant need in order to grow? » Why can’t the plant just take whatever molecules they come by? Why does it have to be

a specific balance of each type?» In this game, the plants run around to find these molecules. How do real plants get

these molecules?

EXTENSIONS

» Flip the game play to have the Plants “rooted” in one spot (they can pivot) and the Sunlight, Water and CO2 running around. The Plant tags what passes by them to form a chain. The end of the chain then can move around to tag the next molecule. (The longer the chain grows, the larger their reach.)


PLANTSPlants We Eat

DEMO

MATERIALS:

• celery stalk with leaves attached

• 2 tall, straight-walled drinking glasses or jars

• water

• red and blue food colouring

• sharp knife

ACTIVITY 5: CAPILLARY ACTION - 45 mins

Students see capillary action . . . in action! Watch coloured water flow up a celery stalk, showing just how water moves from roots to leaves.

All plants need water to survive. Plants use water to carry nutrients to their roots, stems, leaves and flowers and to prevent them from drying out and wilting. But how does a plant move water from the ground up into the rest of the plant? Just as humans have veins and arteries that move blood around inside the body, plants have xylem to move water. This is the plant’s water transportation system. You’ve probably seen old xylem tissue—the rings on a tree trunk. Xylem tissues live for one year, then die, leaving a ring between the old and new xylem.

Xylem tissue is made of millions of tiny tubes made of cellulose. Because water molecules like to stick together and like to stick to the walls of the tubes of cellulose, they rise up the tubes all the way from the roots to the leaves. Water then evaporates from the leaves, helping to draw up more water from the roots. This process is called capillary action.

Celery is handy for demonstrating capillary action because it has a lot of xylem tubes in the stalk, making for fast water uptake. You’ll see the pale green leaves take on a reddish and bluish colour because the dissolved food colouring moves with the water through the xylem tubes into the celery stalk and leaves. The water evaporates through the leaves (transpiration) and deposits the colour in the plant. This helps pull more water into the plant to keep the xylem tubes filled, continuing the cycle of water uptake.

WHAT TO DO

1. Cut the bottom of the stem or stalk with a sharp knife to freshly expose the xylem. Do this quickly so that the openings of the xylem tubes aren’t squished shut.

2. Make a vertical slit about 5 cm (2 in) long in the bottom of the stalk.


PLANTSPlants We Eat

3. Fill two glasses halfway with cold water.

4. Colour one with red food colouring and the other with blue. Use enough drops to make the water a deep colour to get the best effect.

5. Put the two glasses of coloured water next to one another and put half of the stalk into one glass, and half into the other.

6. Wait to see your celery transform! (This could take between 30 minutes (to see a small transformation) and overnight (to see colour all the way to the leaf tips.)

7. Carefully examine the stalk and the leaves to identify the flow of water up the stalk. • Cut the celery stalk in half to see the xylem dyed with the food colouring. • Carefully remove the bulk of the stalk pulp. You should be able to observe

the xylem tubes from a different angle.

KEY QUESTIONS

» How do plants get water from under the ground?» How does water travel into different parts of plants?» Many coastal First Nations groups, like the Haida, have used the bark of trees (which

contains xylem) to make objects like cups and even canoes. How do you think they could remove some of the bark and xylem of a tree without damaging the whole tree?

» What kind of plants have stems that we eat?» What foods that we eat store a lot of water in them?

EXTENSIONS

» Try this with a carnation to see which flower petals are fed by each part of the stem. Leave the flower overnight for best results.

» Do this as a Make & Take activity by providing supplies to each student.


PLANTSPlants We Eat

ACTIVITY

MATERIALS:

Per group

• container and water for soaking beans

Per student

• 2 large lima beans

• 2 pieces of paper

• pencil

• magnifying glass

ACTIVITY 6: SEED DISSECTION - 30 mins

In this activity, the students learn about the plant life cycle by observing and drawing the inside of a seed that is beginning to grow.

We wouldn’t be able to eat plants if it weren’t for seeds. The seed is where the plant life cycle starts. We can learn more about how a seed produces a plant by conducting a seed dissection.

Each seed contains everything it needs to become a mature plant: a tiny plant (embryo) with leaves, stems and root parts, as well as the food it will need to begin growing. This is all wrapped up in a seed coat, which protects everything inside from microbes and other invaders, and prevents it from drying out.

A seed will stay protected inside of its seed coat until there are just the right conditions for it to start growing. When there is enough water and light it will absorb water and use the nutrients inside the seed coat to germinate. That is when the embryo bursts out of the seed coat.

The embryo will grow small roots and shoots that push through the surface of the soil and develop into a small seedling—branches with leaves. Now the plant can begin to produce its own energy from sunlight, water and CO2. The plant matures and grows flowers, fruits, leaves or nuts that contain seeds, and the cycle continues.

This activity was adapted from Beans and their Buddies—An Integrated Primary Science Resource, prepared by BC Agriculture in the Classroom Foundation | http://www.aitc.ca/bc/.

WHAT TO DO

PreparationSoak half the lima beans in water overnight (or for at least three hours) before the dissection. Leave the remaining beans dry for comparison.


PLANTSPlants We Eat

Activity1. Hand out one dry and one soaked lima bean to each student. Brainstorm about seeds: • What are they? • Do all seeds look the same? • What do seeds turn into? • What do seeds need to grow?

2. Draw two large full-page outlines of the beans’ shape.

3. Predict what you’ll see inside of the bean and draw it in one of the bean outlines.

4. Carefully pull open the seeds with a fingernail to see what’s inside. Use a magnifying glass to examine the seeds. Compare soaked beans to unsoaked beans.

5. Draw what you see inside the soaked beans on the second outline. The plant embryo will likely be the same colour as the rest of the lima bean, but it will have a tiny root and two tiny flattened leaves.

6. Compare your drawings, predictions and observations with your classmates.

KEY QUESTIONS

» How are the dry and soaked beans similar? How are they different?» What do you think the skin/seed coat does?» Why is the seed coat so tough? Think of environmental conditions that could affect

the survival of the plant.» How does the seed know when it is a good time to start growing? Does it need

sunlight to grow?» Some types of seeds have thin seed coats, and some have thick ones. Which ones

do you think would survive long, dry winters best? Which ones do you think would sprout quickly?

» What is different about the dry and soaked seed? What do you think would happen if you soaked the seed for even longer?

EXTENSIONS

» Dissect a pea. Does the inside of the pea look similar to or different from the inside of a lima bean?

» Make a list of animals that rely on seeds for food. » Make a list of different types of seeds that humans eat for food. • Seed dispersal is the movement or transport of seeds away from the parent plant.

There are four main ways that plants disperse their seeds: 1. Wind dispersal 2. Hiding in fruit 3. Burrs 4. Flingers» Research each method and determine how the seeds they eat are dispersed. Then get

creative and imagine a new seed dispersal mechanism, using an assortment of materials to build various types and test how well they disperse the seed.


PLANTSPlants We Eat

MAKE & TAKE

MATERIALS:

• thin nylon stockings (the bigger mesh the better)

• peat moss or potting soil

• wheatgrass, alfalfa, chia, arugula, clover or other small sprouting seeds

• cups or mugs

• decorations: permanent paint, glue, buttons, plastic eyes, beads, yarn, etc

ACTIVITY 7: BRAIN SPROUTS - 45 mins

In this activity, students learn about what plants need to grow by growing silly-looking, edible heads.

Learning how plants grow is more fun when you try growing them yourself. Plants need clean air, a source of water, and a source of sunlight to grow and thrive. You can transform seeds into sprouts quickly and creatively in this fun and functional activity. If tended correctly, these edible heads will sprout “hair” within a week and last up to several weeks. Delve deeper into your understanding of how plants grow by growing the edible heads in different conditions.

WHAT TO DO

Activity1. Cut off an 8-inch (20-cm) section of stocking that includes the toe. (You can use a "tube

section" that doesn't include the toe. Tie a knot in one end to close it, then turn it inside-out to hide the knot.)

2. Stretch the stocking over a large cup or mug, and spoon in about 2 teaspoons full of seeds. This is where the top of the head will be and where the “hair” will sprout from.


PLANTSPlants We Eat

3. Pack in some potting soil or peat moss. Aim for the head to be roughly the size of a tennis ball.

4. Tie a knot to close the end. There is no need to cut off the dangly bit. Turn the ball upside down, with the knot on the bottom, and you have the basic head.

5. Make a nose and ears by grabbing a bit of stocking, twisting it, and fastening the base with some thread, wool or a small rubber band.


PLANTSPlants We Eat

6. Create a face with plastic eyes, paints, beads, toothpicks or paint.

7. Once all the paint and glue is dry, water your edible head. Put it in a tray of water so that the peat moss or soil gets completely soaked. Then prop it up in a cup to drain.

8. Water your head by filling the cup with enough water to allow the dangling piece of stocking to touch the water. Capillary action will keep your sprouts moist.

9. Keep the head in a sunny location, and continue to water it from the top every few days or when it gets dry. Depending on which type of seed you use, you’ll have grown a full head of hair between several days two weeks.

10. Style any way you like.


PLANTSPlants We Eat

Experiment1. With a partner or group, create several heads. Try growing each in a different growing

condition. You can try: • Light vs. dark • Various types of seeds • Various amounts of water • Various types of soil • Adding organic fertilizers

2. Record the speed/height of growth in each condition over a period of time and come to a conclusion about the best conditions for the seeds to sprout.

KEY QUESTIONS

» Why do the seeds go into the stocking first? What would happen if you put the seeds in the middle?

» Why do we soak the heads completely first? » Why do we put the heads in a sunny window and give them water?» Why did we stuff the head with soil or peat moss? What other materials could we use?

EXTENSIONS

» Take a picture each day to record growth.» Trim your sprouts into a flat-top style. Measure to see how quickly the sprouts grow back. Use an empty egg carton to plant and label a variety of seeds. Compare how quickly the

different sprouts grow.

NOTES


PLANTSPlants We Eat

MAKE & TAKE

MATERIALS:

Per student

• 2 or 3 seeds (e.g., peas, beans, lettuce, sunflowers)

• popsicle stick

• planting soil mix or topsoil (250 mL per student)

• newspaper cut into a 12 x 22 cm rectangles

• toilet paper roll

ACTIVITY 8: BIODEGRADABLE SEEDLING POTS - 30 mins

Some plants must be started indoors because they are delicate. In this activity, students start seedlings indoors before transplanting them outside.

Starting plants indoors ensures that we can provide the seed and seedling the right conditions for growth. Once a plant is strong enough to withstand the elements, it can be transplanted outside. Newspaper is one biodegradable material we can use to create a pot that will protects the seedling’s root system when it is transplanted. The pot, along with its seedling, can simply be placed in the ground. As the plant grows, the paper will break down and allow the roots to spread.

WHAT TO DO

Part 1: Make the Seedling Pot1. Lay the toilet paper roll along the short side of the newspaper rectangle.

2. Roll the newspaper around the roll. Slide the newspaper so that it overhangs the roll about 20 cm.

3. Fold the overhanging newspaper up inside the toilet paper roll, overlapping it or twisting it to create the “bottom” of the pot.

4. Grip the paper in one hand and the roll in the other. Gently twist the paper pot off the roll.

5. Fold over the top newspaper flap to “lock” the top rim of the pot.

Part 2: Plant the Seed1. Fill the paper with moist soil.

2. Plant a seed in the soil (check the seed packet for suggested depth).

3. Attach a label to a toothpick to identify your seed.


PLANTSPlants We Eat

Part 3: Sprouting and tending the plant1. Put the pot in a sunny spot.

2. Water the pot to keep the soil moist, but not too soggy.

3. Once the shoot has pushed through the soil, the seedling, soil and biodegradable pot can be placed into a bigger pot with more soil, or into a garden.

KEY QUESTIONS

» What do seeds need to grow?» What is different between what the plant and what the seed needs to grow?» Is there anything we can do to make the plant grow faster?» Where can we put the seed to make it grow faster?» What did you give the seed that will make it grow into a plant?» Why did we use newspaper to make the pot?

EXTENSIONS

» Want a simpler biodegradable pot? Simply use a cardboard egg carton, which is already formed into small cups.

» Grow different types of seeds and get students to record seed growth on a chart.» Which seeds grow faster? Which grow slower?» Take photographs or make detailed drawings of the seedlings every day.» What changes do you notice as the plant grows?» Experiment with different types of soil or dirt (i.e., sand, gravel, peat moss, clay, etc).» Does different soil affect the growth of the seed?

NOTES

PLANTSPlants We Eat...the entire food web. Most of the meat and dairy products we eat were produced...

Documents

Transcript of PLANTSPlants We Eat...the entire food web. Most of the meat and dairy products we eat were produced...