This short student activity enables students to experience creating their own microscope slide and to practice using a microscope. The activity reinforces the necessity of finding and focussing on a sample under the microscope first under low power before increasing the magnification.
Stomata are minute structures on plants consisting of two curved cells, called guard cells, surrounding a small pore-like opening called a stoma. Stomata, therefore, are relatively distinctive and easy to find under a microscope. Stomata open (in response to sunlight) to allow gas exchange in leaves and close to prevent it. Gases (specifically water vapour, oxygen, and carbon dioxide) need to be exchanged for photosynthesis to occur. Transpiration is the loss of water through open stomata in the leaf.