Light Lab An investigation to determine how light intensity effects the growth of aquatic and terrestrial plants.

Remember the importance of monitoring light penetration Remember the importance of monitoring light penetration. How does this represent the health of a marine ecosystem? What is this? Sacchi Disk!

“LIGHT LAB” (Label a new piece of paper) PRELAB Questions: 1. The reactants of photosynthesis are _____________. The products of photosynthesis are _________________. What is the final necessary “ingredient”? 2. Where in the cell does photosynthesis happen? 3. Define homeostasis (new word). Scientific Question: Will seeds germinate/grow if they are not in the light? Hypothesis: (MAKE YOUR OWN… IF/THEN) Materials: 10 seeds,2 petri dishes,beaker,water,marking device Variables and Procedures… Independent Variable: Dependent Variable: Control: For procedures… explain what we are doing and have student explain in their own words. Explain directions. Step 1 Your first step is to create a scientific question about photosynthesis. Today you will be manipulating the light that your plant receives. Step 2 After your scientific question, you need to develop a hypothesis using the IFTHEN format. Provide examples as needed and introduce materials to students. Step 3 materials Seeds: You will use mung beans to conduct your research. Remember that mung beans grow very quickly so they are fun to research on! Light: You have the option of using natural and low light conditions. Show procedure for putting seeds in the petri dish with water. Step 4 Allow students to write the set up by asking them to record the independent, dependent and control variables and safety as step 4. Step 5 Write down the steps for your experiment. How will you set it up exactly? Honors gets more freedom here… especially if they were listening to the description of how to set this up Step 6 Create a data table to show how the plants progress from now until Wednesday. Suggest that students count how many seeds appear to be germinating. 10 per dish is an easy number for math that follows. Step 7 Graph…. You will create a graph using the data from your table later on… what type of graphs could we use? (Line change over time…) (Bar could be okay, too) Once your hypothesis and variables have been checked you are ready to begin the lab!

Light Lab Continued… 4. Variables & Procedures Variables: Independent Variable: I am testing how LIGHT affects plants. Dependent Variable: I am measuring how the seeds grow each day. Control: I will use the same petri dish. I will put the same amount of seeds in each dish… etc. Procedures Get 2 petri dishes, 10 seeds and a beaker for measuring water. Divide the seeds in half putting 5 in each dish. Put an EQUAL amount of water in each dish. Label dishes for “LIGHT” and “NO LIGHT”. One will sit in the window. The other will be hidden in a cabinet (away from light). Use this slide to help students understand variables and procedures if needed.

Light Lab Continued… 5. Data Table Try to creat your own. 3 days Light Lab Continued… 5. Data Table Try to creat your own. 3 days.Light VS. NO Light… what can you come up with? LIGHT # of seeds growing NO LIGHT Day 1 Day 2 Day 3 Day 1 Day 2 Day 3 LIGHT # of seeds growing NO LIGHT Having problems creating a data table? Use one of these!

Data Analysis and Conclusion Create a graph to represent your findings in the lab. Conclusion (the hard part…)- Determine whether your hypothesis was right or wrong. You must back up your claims with data from your investigation. Explain the full process of photosynthesis. Be sure to include how reactants and products of photosynthesis were effected in this investigation. How are your findings in the lab relative to real world problems? How are SAV plants effected by light intensity? What environmental factors cause cloudy waters that disrupt sunlight penetration? Make reference to at least 2 of the supplied SAV articles or receive extra credit for finding your own source.