3240-02 Students will investigate changes in biological energy. 3240-0201 Relate energy requirements of plants and animals to physical and chemical changes. Background Information Seeds initially germinate when they absorb water, bursting the seed coat. This starts a chain of chemical changes which will result in the development of the plant embryo. Heat and light are also necessary for the process of germination.
Some plants rely more on heat, others more on light.
Chemical energy stored as starch in the seed is changed to sugar for use during germination. The development of the plant embryo is controlled by hormones as well and a plant can be artificially made to germinate by treating it with the correct hormones. Germination can be recognized by the appearance of a root tip or leaves and stem. Teaching and Learning Strategies Begin the activity with a discussion of the amazing longevity of seeds. Students may be familiar with the idea that seeds have been stored for hundreds of years and then germinated and grown into plants.