(a) (i) What is meant by germination? Germination is the process through which a seed develops into a new plant - Leaving Cert Biology - Question 8 - 2009

Digestion is necessary in a germinating seed to convert stored food substances into simpler, soluble forms that can be absorbed and utilized by the growing embryo. This process ensures that the embryo has the energy and nutrients required for development and growth.

An agar plate is a Petri dish containing a jelly-like substance called agar, which serves as a solid medium for growing microorganisms. It provides the necessary nutrients for microbial growth and allows for the observation of various biological activities.

An example of an extra food material that can be added is starch or milk.

To set up this demonstration, the following steps were taken:

1. Soak the seeds in water to ensure they are hydrated.
2. Split the seeds carefully to expose the embryo.
3. Sterilize the agar plate to avoid contamination.
4. Position the soaked seeds on the agar keeping the plate warm at a temperature not exceeding 35 °C.

The control used for this demonstration consisted of boiled seeds, which are devoid of any living cells, ensuring that any observed activity in the experiment is due to the viable seeds only.

Starch agar was used along with iodine (solution) or milk agar (biuret solution) to observe changes. The presence of a blue-black coloration under the seeds indicated that starch had been digested, confirming the digestive activity.

The experimental plate showed a blue-black coloration under the seeds, indicating successful digestion of the starch present in the agar.

The control plate had no blue-black coloration under the seeds, as expected, confirming that the boiled seeds did not exhibit any digestive activity.