The lesson plan outlines an experiment to investigate how light intensity affects the rate of photosynthesis. Students will measure the rate of bubble production in Elodea over a range of distances from a lamp to determine the relationship between light intensity and photosynthesis. In the first lesson, students will set up the experiment and collect initial data. The second lesson will involve collecting additional data and graphing the results to show how the rate of photosynthesis changes with light intensity. The goal is for students to understand that light energy drives photosynthesis and more intense light results in a higher rate.

1. Lesson title: Light Intensity and Photosynthesis
Class: 11a2 Date:23rd Nov Period: 3 No. Pupils: 16 Boys: 3 Girls:13
Lesson Objectives (WALT):
 Light energy is absorbed by chlorophyll in green plants and used to convert carbon
dioxide and water to oxygen and glucose
Time Activity Content / Notes (key points, questions to ask, assessment of learning, safety)
Before Have all the equipment where needed.
entry
11.14 Starter 6 Recall the factors which affect photosynthesis. If we want to vary light and
mins see the effect what needs to be in good supply and how will we do this?
11.20 Main Outline the practical with discussion on variables, errors, validity etc.
activity 1 Students to draw own results table which is then marked in class. Students
1.5 lessons need to add sodium bicarbonate to provide a ready supply of co2 to make
sure this does not limit the rate.
It’s also a good idea to get the students to practice setting up the experiment
so they know exactly what to do next lesson.
Lesson 2 – collect data and draw graph. Suggest move lamp back from 0 to
about 70cm and count bubbles produced for a minute every 10cm with three
repeats
Plenary Discuss results and what this shows- due the graphs looked like they would
mins expect.
Extra work
Risk Assessment Homework Vocabulary (key words)
Links with previous lessons
Builds on ideas about limiting factors
Specification Links
• Photosynthesis is summarised by the equation: carbon dioxide + water (+ light energy) =
glucose + oxygen
During photosynthesis:
− light energy is absorbed by a green substance called chlorophyll which is found in chloroplasts
in some plant cells this energy is used by converting carbon dioxide and waterinto sugar (glucose)
− oxygen is released as a by-product.
Equipment
Elodea, Sodium bicarbonate, Spatulas, Paper clips, Boiling tubes, 250ml glass beakers
Meter rules, Stopwatches, lamps, Graph paper