Download Mission 2

Mission 2 – page 1
Name: _________________________
Teacher: _______________________
Mission 2: The Root of the Matter
Mission 2: So now we know more about the Moon's environment. Since our goal is to
grow plants on the Moon, we need to learn more about plants and how they grow on
Earth. Then, we will start to put the information together!
Sections:
Plant Parts
Making New Plants
Plants and Gravity
Plant Parts
In this section, we will learn the parts of plants. Plants have roots that anchor the plant
in the soil and hold it in place. Roots also take in nutrients and water from the soil. The
stem acts as a highway to move water and nutrients from the roots to other parts of the
plant. Plants are called herbaceous or woody based on their stems. Herbaceous
plants have soft stems that usually die back to the ground during the winter. Woody
plants are tough and their stems do not die back to the ground.
Mission 2 – page 2
Nutrients and water travel from the stems to the leaves. The leaves then use the water
and nutrients along with sunlight to make sugar. The sugar is sent to other parts of the
plant. The process in which plants make food is called photosynthesis. In
photosynthesis, the leaves use carbon dioxide from the air, nutrients, water, sunlight,
and a substance called chlorophyll to make sugar, which moves to other parts of the
plant like stems, root, flowers, and fruits. The process of photosynthesis releases
oxygen into the air.
Leaves can come in many different shapes and
sizes. They are designed to catch light and
have many openings called stomata that let
air and water come and go. You can only see
stomata using a microscope. Leaves are
covered with a waxy coating called a cuticle
that protects them.
Making New Plants
When we think about how to grow new plants, most of us think of planting seeds. Each
seed is really a tiny plant in a package. Seeds are protected by a seed coat that can be
thick or thin. Seeds have all of the materials inside of them that they need to form
leaves, stems, and roots. But, seeds stay dormant until the conditions are right for them
to begin to grow, usually warm and wet. Germination is when a root and a shoot begin
to grow out from the seed. This is the beginning of a new plant!
Mission 2 – page 3
There are many things that can go wrong to cause poor germination. If a plant gets too
much water, then it might not have enough oxygen to grow. Also, very dry conditions
might mean that the plant cannot get enough water to germinate. If seeds are planted
too far in the ground, they might use up all their energy before they can get to the
sunlight.
Some plants have flowers. Flowers are not only pretty to look at, but this is where seeds
come from. Flowers can be made up of different parts, but there are some parts that all
flowers have. Sepals are the green petal-like parts at the bottom of the flower. Sepals
help protect the flower buds. The main flower parts are the male part called the stamen
and the female part called the pistil. The stamen is made of anthers and filaments. The
anthers carry the pollen and are generally yellow in color. Anthers are held up by the
filaments, a thread-like part.
The pistil is made of a stigma, a style, and an ovary. The stigma is the sticky surface
at the top of the pistil that traps and holds the pollen. The style is tube-like and holds up
the stigma. The style leads down to the ovary that holds the ovules. When pollination
happens, pollen moves from the male parts to the female parts. Pollen grains land on
the stigma. Then, a tiny tube grows from it and down the style into the ovary. The ovule
then becomes the seed and the ovary becomes the fruit.
Mission 2 – page 4
Pollen moves from the male to female plant parts with the help of insects, the wind, and
animals. Since flowers can't move, they need to get pollinators to come to them some
other way. That is one reason why flowers are bright colors and smell good--to attract
insects and animals. Flowers may be built so that wind is able to pollinate them or so
that pollen can stick to the hair of animals as they pass by the flowers. Bees, butterflies,
insects, and birds like the bright petals and sweet nectar of flowers. Some flowers open
at special times for pollinators, such as plants that open at night and are pollinated by
bats.
Some plants do not have flowers. Plants such as ferns, mosses and mushrooms make
spores instead of seeds. Ferns make their spores under their leaves. They look like
brown spots on the bottom of the leaves.
There are still other ways to grow a new plant! A bulb is a tiny packaged-plant that has
everything necessary to grow a new plant. Bulbs have carbohydrates to feed the plant
and places for the roots to start growing. Everything is wrapped up very neatly in a
tunic. The tunic protects the bulb from drying out. Inside the bulb are scale leaves.
They are baby leaves that hold stored food for the bulb.
Other ways to grow new plants are with tubers and cuttings. A tuber is a fat stem that
grows underground and is used for food storage for plants. A cutting is a piece of a
plant's stem, root, or leaf that is planted and grows roots.
Mission 2 – page 5
Yummy Plants
People eat many different plants in our daily diet. But did you know that we eat all parts
of the plants?
AstroNut - Hi! I'm AstroNut, and I am a peanut. The peanut plant is
unusual because its flowers are above the ground, but its fruits are
below the ground. Peanuts have oval shaped leaves and are about
18 inches (about 30 cm) tall. Flowers develop around the lower
portion of the plant. The flowers pollinate themselves and then lose
their petals as the fertilized ovary begins to enlarge. The budding
ovary or "peg" grows down away from the plant and forms a small
stem that extends to the soil. The peanut embryo is in the tip of the
peg, and it penetrates the soil. The embryo turns horizontal to the soil
surface and begins to mature, taking the form of peanut. The peanut plant continues to
grow and flower, eventually producing some 40 or more mature pods. From planting to
harvesting, the growing cycle takes about four to five months, depending on the type or
variety.
Broc - What's up? I'm Broc, and you guessed it - I am a broccoli
plant! The edible portion of the broccoli plant is made up of the
tender stem and the unopened flower buds. Broccoli from fields
is harvested in the early morning because it wilts very rapidly in
the sun. Field crates or baskets full of broccoli are then taken to
a packing shelter where the broccoli is bunched and iced. The
broccoli head (which is what I am) should be cut before the
flower buds open. If the buds begin to open and the yellow
flower petals begin to show, then the head is over-mature and
unfit for market. Broccoli heads for market should be about 9 to
10 inches (about 22 to 25 cm) from the base of the stem to the
top of the head.
Polly - Howdy! My name is Polly, and I am a strawberry. Plants like me
have white, sometimes pink (depending on the variety) flowers that turn
into luscious strawberries to enjoy fresh, put into desserts, make jam,
or freeze and use later. Strawberry plants develop runners, or baby
plants that are attached to the parent strawberry plant. Strawberry
plants grow 6-8 inches (15-20 cm) tall spreading about one foot (30.5
cm) across with long runners. Strawberries like well-drained and fairly
rich soil, so be sure to add compost or other organic matter when
preparing the strawberry patch. We need full sun, and frequent, deep soakings, so also
be sure to give adequate water during fruit-bearing season.
Mission 2 – page 6
Tate - Hello there! My name is Tate, and I am a potato. Potatoes are
tubers, which means we are a special kind of stem that grows
underneath the soil. Potatoes are an excellent choice for the home
garden. We emerge quickly and grow rapidly. Potatoes grow well
under most soil and growing conditions and can be stored for long
periods without canning, drying, or freezing. Potatoes are not only
delicious but also highly nutritious. Tubers are a good source of trace
minerals and several vitamins, including vitamin C. To grow potatoes,
people order seed tubers and cut them into several pieces. The ideal
seed piece is blocky in shape, has as few cut surfaces as possible,
weighs between 1 and 2 ounces (between 28 and 52 grams) (slightly larger than a golf
ball), and has two or more "eyes" or buds.
Plants and Gravity
So, do plants grow the same way in space as they do on Earth? Scientists are learning
more about how plants grow in space every day. Gravity plays an important part in plant
growth. Remember when we learned in Mission 1 about gravity, the force of attraction
that keeps our feet firmly planted on the Earth? We know which way is down because of
gravity's pull on us. Well, plants also use gravity to know which way is down. The root
tips of plants have special starch grains inside called statoliths. These grains are
heavy. They fall to the bottom of the root tip cells and act as a signal. They tell the plant
which way is down. If you tip a plant on its side, the heavy grains in the root tip would
again be pulled down by gravity, and this would tell the plant which way is down. The
root would then start growing in that direction.
In the same way that roots use gravity signals to grow downward, shoots use these
signals to grow upward. Shoots also use light to tell which way to grow. Shoots grow
towards light, and away from gravity. These plant movements are called tropisms
(gravitropism for gravity and phototropism for light). Scientists want to understand the
signals inside a plant that help the shoots to know to grow up and the roots to know to
grow down. In spaceflight, where the plant does not have gravity to help the roots and
shoots to orient, plants usually get confused and grow in a mixed-up way. In a
microgravity environment, the starch grains should float around randomly, just like
astronauts do. Instead, scientists have found that they bunch together. Why? It's part of
the mystery. Maybe one day you will help to solve it!
Mission 2 – page 7
Plant Report
Look back at the information you have learned in Mission 2 and write a report on the
next page to Commander Spud Goodroot answering the following questions:
1. What are the major parts of plants and what do these parts do?
2. What are four parts of plants that you can use to grow new plants?
3. How do plants and humans depend on each other to live?
4. If you had to decide right now three plants to take with you to the Moon, which would
you take and why?
Congratulations! You have completed Mission 2!
Mission 2 – page 8
Mission 2 Glossary
air
substance needed by many living things including plants, animals,
and humans
anther
the male part of the flower that produces the pollen
bulb
a miniature packaged plant that contains everything needed to grow
a new plant, made up of special scale leaves and food for the plant
carbohydrate
an organic compound such as sugar or starch which provides
energy for living organisms
carbon dioxide
a gas from the air that is used by plants for photosynthesis, also
known as CO2
cells
the basic structural and functioning units of all living things
chlorophyll
green material in plants that is created in the presence of light and is
important for photosynthesis
waxy coating that protects the leaf
cuticle
cutting
a part of a plant's leaves, roots, or stem which is planted and grows
into a new plant
dormant
being in a resting state (not currently growing)
exhale
to breathe out
filament
fine stalk that holds up the anther
flower
reproductive part of a plant
fruit
ripe, mature ovary that contains seeds
germination
activation of a seed that causes it to start to grow
glucose
a simple sugar that plants make and use as food
gravitropism
the response of plants to gravity; roots move towards the pull of
gravity and shoots move away from the pull of gravity
Mission 2 – page 9
herbaceous
leaf
describes plants that have stems that are soft. These plants die
back to the ground in the winter.
green part of a plant that collects light and carbon dioxide for
photosynthesis
nutrients
sources of nourishment for living things that are important for growth
and survival
orient
to become adjusted and position oneself; to align with respect to a
point of reference
ovary
part of the female flower that contains the ovules
ovule
part of the ovary that becomes a seed
oxygen
substance released into the air by plants as a result of
photosynthesis. Plants take in carbon dioxide and release oxygen
while humans take in oxygen and release carbon dioxide.
petal
specialized structure that protect the parts of a flower and also
attract birds and insects to help with pollination
photosynthesis
process by which a plant produces food using water, carbon dioxide,
and sunlight
pistil
female part of the flower that includes the stigma, style, and ovary
pollen
yellow powder-like material on the anthers which is necessary for a
plant to reproduce
pollination
movement of pollen from the anther to the stigma
root
underground part of a plant that collects water and nutrients from
the soil; also anchors the plant
cells at the very tip of a plant root containing particles that respond
to gravity and help direct the root to grow down
root tips
scale leaves
the small leaves inside a bulb that hold stored food for the bulb
seed
part of a plant that will grow into a new plant if the environmental
conditions are right; formed by the maturation of the ovule after
fertilization
seed coat
protective outer covering of a seed
Mission 2 – page 10
sepal
shoot
green leaf-like structures that cover a bud and later open up to
reveal the petals of a flower
emerges from a seed that has germinated and becomes the part of
the plant that grows upward
spore
seed-like structure that plants like ferns, mosses, and mushrooms
use to reproduce instead of a seed
stamen
male part of the flower that includes the anther and filament
statoliths
special starch grains in the bottom of root tips which tell the plant
which way is down
stigma
sticky surface on the end of the pistil that traps and holds pollen
stem
part of the plant which holds up the leaves and flowers and serves
as a highway to move water and nutrients through the plant
stomata
pores in leaves that allow plant to bring in carbon dioxide and
release oxygen
style
part of the female flower that holds up the stigma
tuber
a fat stem that grows underground and is used for storage for plants
tunic
the outside portion of a bulb that protects it from drying out
water
substance formed of hydrogen and oxygen needed by many living
things including plants, animals and humans
woody
describes plants that have stems that are hard and stiff, such as
trees