Unit C



Photosynthesis and cellular respiration are essential processes in all ecosystems.  In Unit C you will explore the intricate pathways followed by the processes of photosynthesis and cellular respiration.

Photosynthesis and cellular respiration are two processes essential to your existence. If plants could not perform photosynthesis, you would have no food to eat or oxygen to breathe. Without cellular respiration, your body would not be able to use any of the stored energy in food and your cells would not function. It would be as if your gas tank was full, but your engine didn't work.

The life processes of photosynthesis and cellular respiration allow for the transfer of energy and matter. This unit will take a closer look at the pathways involved in energy transfer and the resulting intermediate products.

Big Ideas

This unit consists of one module. This module will explain how photosynthesis stores energy in organic compounds, such as sugars, and how cellular respiration releases potential energy from these organic compounds.

By the end of this unit, you should be able to

  • describe how photosynthesis enables the conversion of light energy into chemical potential energy within organic compounds

  • explain the role of cellular respiration in releasing potential energy from organic compounds for use by organisms

Key Concepts

Concepts that you should be able to explain by the end of this unit are
  • absorption of light by pigments in the chloroplast
  • light-dependent and light-independent reactions of photosynthesis
  • the energy potential of ATP and its role in cellular activities
  • electron transport systems and chemiosmosis in photosynthesis and cellular respiration
  • the reducing power of NADPH, NADH and FADH2
  • aerobic and anaerobic reactions in cellular respiration
  • glycolysis and Kreb's cycle reactions in cellular respiration


Skills that you should be able to do by the end of this unit are
  • relate the absorption of light by various pigments to the production of glucose
  • analyze the results of a chromatography experiment
  • calculate the Rf value from chromatography data
  • predict the effect of light intensity, light wavelength, temperature, and carbon dioxide concentration on the rate of photosynthesis


There are four graded assessments in Unit C.

  1. Unit C: Section 1 Assignment
  2. Unit C: Section 2 Assignment
  3. Unit C Summative Assessment
  4. Unit C Test

As you work through this unit and its module, you will find Self-Check questions,  labs, and critical thought questions. There will be lesson goals indicated at the beginning of each lesson and then clearly identified throughout the lesson.