Supports the plant and transports materials throughout. Anchor plants in the soil while absorbing, transporting, and storing nutrients.

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1 Unit 3 Review: Plants as Producers Still having trouble with photosynthesis? Here s where you can go for more help: Plant Structures 1. Describe the function of each of the following plant structures Plant Structure Function Root hairs Greatly increases the surface area of the root, allowing for more absorption of water and minerals. Stem Petiole Root Blade Supports the plant and transports materials throughout. Connects the stem to the blade. Anchor plants in the soil while absorbing, transporting, and storing nutrients. The broad, flat part of the leaf, used for collecting sunlight. 2. Draw a simple plant and label each of the structures from the list petiole 3. blade 1. stem Root hairs roots 5. The Process of Photosynthesis 3. Define photosynthesis Photosynthesis is the process by which plants take energy from light and use it to combine water and carbon dioxide to produce glucose as food 4. Describe in full sentences what is the purpose of photosynthesis To produce food for the plants 5. Write down the equation for photosynthesis. Circle the reactants and put a rectangle over the products CO2 + H2O Sunlight O2 + C6H12O6

2 6. Summarize each stage of photosynthesis in the table below. Make sure to describe what happens at that stage and what is needed: Capturing light Light dependent Light independent The pigment chlorophyll that is in the cell organelle chloroplast on the blade of a plant, absorbs some colors of light. The energy from the sun is used for splitting the water molecule into hydrogen and oxygen. The energy is changed from light energy to chemical energy and stored in the ATP. The hydrogen that came from the water is used with the carbon dioxide to assemble the glucose. The chemical energy from the ATP is used in the process and stored in the glucose (food). 7. Order in the correct sequence the energy transformations that occur during photosynthesis (stored in glucose, light energy, chemical energy) light energy chemical energy (ATP) Food (glucose) Pigments, absorbance and transmittance 8. Define pigment and name the main pigment involved during photosynthesis. A pigment is a compound that absorbs certain colors of light and transmits others 9. Explain using the words absorbance and transmittance why cranberry juice looks red under sunlight. Cranberry juice looks red because it transmits the red color and absorbs non-red colors Oxygen and carbon dioxide in plants Given the following experimental setup: An airtight container is set-up with an oxygen and carbon dioxide sensor. The plant is plant is placed in the sunlight. Explain what happens to the levels of CO2 and O2 in the container Sunlight O2 : Will inccrease with time CO2:_ will decrease with time

3 History of photosynthesis studies 10. In the table below, write the name of the scientist, the experiment that they performed (what they did) and their contribution (what they found) to the study of photosynthesis: Scientist Experiment Contribution Jean Baptiste van Helmont Placed a plant in a pot with soil >measured the mass of the soil and plant. Watered the plant and later measured again plant and soil. He found that the plant gained a lot more mass than was lost by the soil Showed that Aristiteles idea that plants gain mass from soil was wrong. He proposed plants gain mass from water Joseph Priestly He placed a lit candle under a bell jar so that it was air-tight. Once the candle went out, it could not be lit again. Without lifting the bell jar, Priestly tried to relight the candle by directing the sun s beams through a magnifying glass. Priestly then tried the experiment again, but this time, he placed a sprig of a green plant under the bell jar with the candle. Again, the candle burned out, and could not be lit again. However, he noticed that after a few days, the candle could once again be lit. Showed that plants restore the air so a candle can be lit. Jan Ingenhousz Same experiment as Priestly but under light Showed that plants can only restore the air when light is present. He also replaces CO2 instead of bad air, and O2 instead of good air. He also proposes that plants obtain food through photosynthesis Nicholas Theodore de Sassure showed through careful experimentation that water (H2O) was an essential part of the process of photosynthesis He concluded that the increase in mass was more than would amount from the intake of CO2 alone. He believed that once the CO2 was split, the carbon combined with the H2O to form the plant s food. C.B. van Niel Not given in the reading Showed that the oxugen given by plants comes from the splitting of water into hydrogern and oxygen

4 Absorbance and transimmitance The absorbance and transmittance analysis was performed on a random liquid. The results are recorded on the table below: Plot the data on the graph below. The wavelength in nm should be placed on the x-axis. The absorbance should be plotted on the left vertical y-axis. The transmittance should be plotted on the right y-axis. Be sure to label or color code each line as you draw a smooth curve through the data. Remember to include a title and labels for each axis! 11. Based on the table and/or graph, what color is the liquid? Explain your answer: Red. The red wavelengths are being transmitted more than the other wavelengths. The colors that are not red are being absorbed more than the red wavelength. Wavelength in nanometers (nm) And color Absorbance Value (Range 0-2) Percent of wavelength transmitted (Range 0-100) 400 (Violet) (Violet) (Blue) (Blue) (Green) (Green) (Yellow) (Orange) (Orange) (Red) (Red).7 42

5 Absorbance and transmittance of light for different wavelenghts Absorbance Transmittance Absorbance Transmittance Wavelength (nm) 0