Summary Coordinated Science - IGCSE - Biology - Plant Nutrition

Chapter 4 - Plant Nutrition
I. Photosynthesis
 Photosynthesis is the process in which light energy is converted to chemical
energy in the form of sugar
a. Chlorophyll
 The substance plants use to trap the energy from light
 Chlorophyll is a pigment that gives green plants their color. It is stored inside
chloroplasts in the leaves
 The energy is used to add carbon molecules to a premade 5 carbon
molecules to make glucose (carbon fixation)
 Light energy → chemical energy
b. The Photosynthesis Equation




II. Leaves
a. Leaf Structure
 Leaves consists of wide lamina around veins branching out from the midrib
 Vasular bundles running through the petioles, up the midrib and through the
veins supply water and carry products from photosynthesis to where it is
needed




Cuticle  waxy layer that protects the leaf from drying out
 stops water from evaporating from the leaf
 covers the epidermis on the top and bottom of the leaf
 no chloroplast

Upper epidemis  single layer of cell
 contains little to no chloroplast
 cells secrete a waxy substance that lies on top (cuticle)