Module 5 Intro
1. Module 5 Intro
1.1. Big Picture
Module 5—Photosynthesis and Cellular Respiration
Big Picture
People have a need for energy. Energy is required to run everything from a huge power plant to a single cell. Luckily, people have access to an unlimited energy supply—the Sun. Essentially, all available energy on the planet is derived from the Sun. Earth’s entire biosphere has evolved as an ultra-efficient means to transform solar rays into the chemical energy required for life. Plants have evolved to transform solar energy to potential chemical energy. Animals, such as humans, have evolved to transfer potential chemical energy into many other energy forms.
Science and technology are important in today’s society. This is particularly so with concerns over the rising environmental and economic costs of limited non-renewable energy sources and with the deforestation of large tracts of vegetation.
Technology is produced to enhance or mimic the processes of photosynthesis and cellular respiration. What fundamental principles are the basis for this research and technological advancement?
© Uli Hamacher/iStockphoto
As you discovered in Unit A, massive vegetation equals high plant productivity. Increasing population pressures may create havoc on Earth by reducing the amount of vegetation and, thus, the ability for photosynthesis to support the biosphere. Therefore, it is essential to understand the minute details of the process of photosynthesis and exploit it. What are the opportunities for applying what is known about photosynthesis?
Photosynthesis-based technology could include using the concept of efficient "energy capture" to artificial systems just as plants have been doing. Research is being done in Berkeley, California, on getting green algae to convert water to hydrogen to be harnessed as a
clean-burning fuel. Currently, technology has developed herbicides that inhibit photosynthesis in order to kill weeds.
The value of applying knowledge of cellular respiration has also been utilized in the multi-billion dollar wine industry. Globally, 27 billion litres of wine are made each year. This is an industry where new technologies are being developed to enhance cellular respiration and photosynthesis for the benefit of taste and economics.
Photosynthesis and cellular respiration are the most important biological processes on Earth. Without these two processes, how would the transfer of energy and matter occur?
You will explore the following essential questions in this module:
- What pathways do energy and matter follow in living organisms?
- How does the energy from light flow through living systems?
- Why is oxygen produced during photosynthesis?
- How is carbon dioxide used during the light-independent reactions of photosynthesis?
- How are ATP and NADPH produced by the light-dependent reactions used to make glucose?
As there is only one module in Unit C, there is only a unit assessment for you to consider as you work through Module 5.
As you work through the module, make note of questions or concepts that were particularly challenging or thought-provoking. This list will be helpful when you are ready to complete a unit test as part of your Unit Assessment. You will find the details for this assessment and an evaluation rubric in the Unit Summary section.