Biology 110
Unit 3: Take Home Assignment
Please type your answers. You may refer to your text book and lecture notes to answer questions. Do NOT use the Internet. While you may work together, your answers should be in your own words. Answers should be brief and concise. No more than one page for the entire assignment! Drawings are encouraged. 10 points.
1. In the dark, plants show a net production of CO2 and net absorption of O2. When exposed to light, they show a net absorption of CO2 and net production of O2.
a) What biochemical process is responsible for the plants absorption of CO2 and net production of O2?
a. Photosynthesis is responsible for the carbon dioxide absorption and the production of oxygen.
b) What biochemical process is responsible for the plants absorption of O2 and net production of CO2? Does this process occur in the presence of light?
b. The opposite of photosynthesis is respiration carbohydrate and oxygen is the reactant and water, carbon dioxide, and energy are the products.
c. No this process does not require light because as light starts decreasing (as it becomes dark) the level of CO2 absorption decreases and CO2 production increases.
c) Why aren’t the net production of CO2 and net absorption of O2 seen in the presence of light? Explain briefly.
d. Usually the plant uses the energy of light to breakdown CO2 to make oxygen. Since there is no light now the plant needs to make CO2 and now the process works the other way oxygen combines with sugars to make water, CO2, and energy.