Radish Seed Lab!
Name ________________________________ Hr. ___
Thanks to: http://www.sciencebuddies.org/science-fair-projects/project_ideas/PlantBio_p008.shtml for ideas and information
REES- Biology
Objectives:
1. To identify characteristics that distinguishes living organisms from non-living
objects.
2. To propose and predict the factors that may affect the rate of germination in the
Radish seeds.
3. To design and perform an experiment in which correct scientific method is used.
Introduction:
You might already know that if you plant a seed it will grow into a plant. But did you know
that inside of every seed is a baby plant? The inside of a plant seed has three main parts:
the embryo is the baby plant, the endosperm is food for the baby plant, and the
cotyledon(s), which look like leaves and contain the endosperm. All of the parts of the baby
plant are enclosed and protected by a special covering called the seed coat. The seed coat
protects the baby plant embryo from many different conditions, some of these conditions
can be: drying out, freezing temperatures, heat, radiation, or acidity.
Reading check: What are the 3 parts of a plant seed? ___________________________________________
Some seeds have very large and tough seed coats while others have very weak and fragile
seed coats. This is because different kinds of plants have adapted to different
environments, and so need to be protected from different things. Desert plants need
protection from drought, arctic plants need to be protected from cold winter temperatures,
and plants from pine forests often need protection from forest fire. In fact, seeds from some
forest plants need a forest fire before they can sprout through their tough, protective seed
coats!
Reading check: What is one advantage for pine trees in a mountainous area to have a very
tough outside seed covering? ____________________________________________________________________
Seed sprouting is called germination, and is the process during which the baby plant
emerges from the seed and develops its first set of true leaves. Germination begins when
the seed absorbs water, which causes the endosperm to swell and pop open the seed coat.
Then the embryo will grow and develop its first set of true leaves, using food stored in the
endosperm for energy. Some seeds take a very long time to germinate, while others
germinate very quickly. For this experiment, we have chosen radish seeds, which
germinate very quickly in 3 to 5 days.
Reading check: Write out (summarize) the 2 steps of germination. ____________________________
_______________________________________________________________________________________________________
Plants use energy from the sun to grow and make food in their leaves. Some of the sun's
energy is in the form of ultraviolet radiation, sometimes called UV rays. The UV radiation
from the sun is one kind of electromagnetic radiation. Electromagnetic radiation is also
produced by many household appliances, like radios, cell phones, televisions, and your
microwave. When you use a microwave, the microwaves travel through your food, causing
the food to cook. In this experiment we will use a microwave to expose our seeds to
electromagnetic radiation. Sometimes electromagnetic energy can also cause heat, and in
our experiment we will heat our seeds by baking them in the oven.
Reading check: What type of radiation makes your cell phone work? __________________________
Terms, Concepts and Questions to Start Background Research
To do this type of experiment you should know what the following terms mean. Find their
definitions and write them out below. You may also draw a picture and label it if that helps
you remember what each term means.
 seed coat (testa)-
 shoot (plumule)-
 germinate-
 cotyledon-
 root (radicle)-
Let’s Experiment!
Materials and Equipment
 radish seeds
 permanent marker
 water and a dropper
 oven
 aluminum foil
 microwave
 tape
 a sunny window or
grow lamps
 napkins
 Zip-Lock baggies
Experimental Procedure
1. Before you start, have an adult preheat the oven to 250 degrees.
2. Now you can start to set up your experiments. To set up for each experiment, you will need to do a lot of labeling
and organizing, so that your seeds won't get mixed up with each other. To do this you can label each zip lock
baggie with a permanent marker.
3. You will need to label one baggie for your "control" group, one baggie for each group of microwaved seeds, and
one baggie for each group of baked seeds. Label each microwaved seed baggie with "MW" and the time you
microwaved your seeds: "10 seconds," "20 seconds," "30 seconds,” Label each baked seed baggie with "B" and
the time you baked your seeds: "10 minutes," "20 minutes," "30 minutes,". (We will actually do this as a class;
each table will have one of these bags assigned to them.)
4. Now you are ready to turn each baggie into a miniature greenhouse. Place a folded napkin in the bottom of each
baggie making sure it lies nice and flat.
5. Add a few drops of water into each baggie until the napkin is evenly moist, but not dripping wet. Keep the
baggies ready, so that as you treat your seeds you can put them inside the baggies, zip the baggie closed, and
tape it to a sunny window.
6. One more important thing to do is to set up a "control" group. This group of seeds will not be microwaved or
baked in the oven. The reason for having a control group is so that you know your seeds are good and can
sprout. What if the seeds you bought are bad? For this group, take the bag labeled "control" and add 10 radish
seeds to the bottom of the bag on one side of the napkin, close the baggie and tape to the window.
7. For the microwave experiment, you will be taking groups of 10 seeds and microwaving them for different
amounts of time. Count out 10 radish seeds, place on a dry napkin, and microwave for a period of time (10, 20,
or 30 seconds).
8. Place the seeds into the matching bag with the correct label, close the bag, and place it under the grow light.
9. For the baked seeds—remember the oven will be very hot! Make some little squares of aluminum foil and fold
up the outer edges to put your seeds into.
10. Place each little tin on a cookie sheet and fill with 10 seeds.
11. Place the entire cookie sheet onto the oven, which has been preheated to 250 degrees.
12. Take out a group of seeds about every 10 minutes, so that the time in the oven will match the time on each
baggie.
13. Place the seeds into the matching bag with the correct label, close the bag, and place it under the grow light.
14. Let all of your experiments sit under the grow light for 3 to 5 days. After that time you will notice that some of
the seeds have sprouted. Do not open the bags or add water during this time, if they were sealed properly they
will not dry out or run out of air.
15. After the seeds have sprouted, write the number of sprouted and un-sprouted seeds on the baggie for each
group. Record your data in this table:
Group
Time Treated
Control (MW)
none
Control (B)
none
Microwaved
10 seconds
Microwaved
20 seconds
Microwaved
30 minutes
Baked
10 minutes
Baked
20 minutes
Baked
30 minutes
Number Sprouted
Number Un-sprouted
16. After you have finished counting up all of your seeds and sprouts, you are ready to make a graph. There are
many different types of graphs you can use for this experiment. The simplest type of graph will be a bar graph.
On the left side of your graph, called the Y-axis, you will put the number of seeds sprouted from 1 to 10. On the
bottom of the graph you will put your different groups. Draw a bar for each group that indicates how many
seeds sprouted for that group.
17. From your graph, you can compare the seeds from your different experiments to your control seeds. Do more
seeds sprout, or less seeds sprout in your experiments? What do you think happens when the seeds are
exposed to microwaves? What do you think happens when the seeds are heated? What does this tell you about
seeds?