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A. Take a seed that has
been soaked in water for four hours and gently ease it open
without disturbing the inside structures. Observe these
structures using a binocular microscope. The outside structure
of the seed has already been drawn and labelled for you. Now
draw the inside structure of the seed and using the following
labels.
Seed coat, food
store (cotyledons), root
(radicle), shoot
(plumule)
B. Now remove the seed
coat from one half of the seed. Add to the seed, three drops
of iodine solution. What do you observe?
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This is a positive test for a complex sugar called
starch. It is the food store for the seed.
C. Now cut open the
storage organs and put three drops of iodine
solution onto a part that you have cut open. What
do you observe?
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What do these storage organs contain?
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Conclusion
Seeds and storage organs contain food to allow the plant to
start to grow again the following spring.
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