Is Light Needed For Germination?

INTRODUCTION

When seeds are developing, the seeds go through several stages, the last being dehydration to become an inactive seed. The inactive seed is what can be bought at the store in packets. For seeds to be active again, the proper conditions such as warmth, water, and oxygen are needed. These conditions lead to the seed germinating. Germination comes from the Latin root germinare, which means "to sprout", and germen, meaning "seed". Lets determine if sunlight on the soil is necessary for germination.

Germinating Seed

MATERIALS

WHAT TO DO

  1. To make germination trays take one egg carton and cut off the top half and place it under the bottom half. Take the second egg carton and cut off the top half, placing it under the third carton. The trays under the cartons will catch excess water.
  2. Use a pencil to punch a hole in each top layer compartment in both cartons to allow drainage.
  3. Fill each compartment approximately half way with potting soil.
  4. Sprinkle a few seeds in each compartment of the egg cartons, then add enough soil to cover the seeds.
  5. Water each compartment until the soil is moist.
  6. Close the lid of the second egg carton.
  7. Place the egg cartons in the window to receive sunlight.
  8. Check each day for growth and if the soil is moist. Water as needed.

QUESTIONS

  1. In which egg carton did the seeds germinate?
  2. Did more seeds germinate in one of the cartons? If so, which one?
  3. Is light necessary for germination?

SUMMARY

Germination is the process by which seeds sprout. Seeds must go through several stages of development before being ready to sprout. Light on the soil was not necessary for seed germination because warmth, water, and oxygen are the only conditions necessary for a seed to germinate. This is because the seed contains the plant embryo and stores enough food to give the baby plant all the energy it needs to sprout. After the seeds sprout and use up all the stored food, they do need light to grow. The light is needed for photosynthesis, which thereafter provides the plant’s food source.

SOURCE

"Janice Van Cleave’s Plants." Janice Van Cleave, John Wiley and Sons, Inc.: New York, 1997. ISBN 0-471-14687-0

© S. Olesik, WOW Project, Ohio State University, 2003.

Print Version   Plants Experiments   Main Experiments Page   Home