9. (a) (i) Yeasts are eukaryotic organisms - Leaving Cert Biology - Question 9 - 2005

To collect the leaf sample, I ensured that I wore gloves to prevent contamination. I carefully cut the leaf using sterile scissors, placing it into a clean container to avoid any contamination from the environment or my hands.

Upon returning to the laboratory, I placed the leaves in a labeled petri dish to ensure proper identification. I then proceeded to prepare them by cutting them into smaller pieces, making it easier to cultivate the yeast.

Nutrient agar plates are solid culture media containing nutrients that promote the growth of microorganisms. They typically include peptones, agar, and additional growth factors. The purpose of using these plates is to provide a controlled environment that allows yeast cultures to grow and reproduce.

At the end of the experiment, I observed the presence of pink colonies on the agar plates, which indicated the successful growth of yeast from the leaf sample. In some cases, negative results showed no growth at all.

After concluding the experiment, I disposed of the agar plates safely by placing them in a biohazard waste container to prevent any potential contamination or spread of microbial cultures.