Photosynthesis, a Look Inside the Leaf

 

Catarina Mata

Tested Studies in Laboratory Teaching, 2018, Volume 39

Abstract

This cheap and easy photosynthesis lab is an alternative or complement to gas exchange and light absorbance labs. Students will understand the relations between structure and function in photosynthesis. After learning the functional differences between C3 and C4 plants, students will try to locate in easily available fresh leaves where they think most cells are doing photosynthesis based on chloroplast abundance. Students prepare fresh leaf cuts, and epidermal peels. Learn basic leaf anatomy and look for evidence of photosynthetic locations. Students draw the structure and explain the path from sugar producing cells to the phloem and from outside CO2 to the fixation sites. If time allows, students are provided leaves from different habitats and relate adaptations such as leaf cuticle, sunken or exposed stomata, leaf thickness and other traits to the environment the leaves are from and the challenges they face. Prepared slides of standard C3 and C4 leaves, mono and dicots are desirable to complement fresh samples that turn out to be a little thicker. This lab requires only microscopes, razor blades, glass slides and leaves picked around campus or at the grocery store.

Keywords:  photosynthesis, leaf anatomy, leaf epidermis, stomata

University of Wisconsin, Madison (2017)