Name: Emery Gates Date: 04-04-2022 Student Exploration: Seed Germination Directions: Follow the instructions to go through the simulation. Respond to the questions andprompts in the orange boxes. Vocabulary: controlled experiment, germinate, hypothesis, mean, seed, trial, variable Prior Knowledge Question (Do this BEFORE using the Gizmo.) Plants that produce fruit or vegetables grow from seeds . Suppose you want to start a vegetable garden using seeds. How could you get the seeds to sprout? To ensure that the seeds form roots, I would plant them in healthy soil. Gizmo Warm-up Seeds are only able to sprout, or germinate , under the right conditions. The seeds of different species of plants need different amounts of light,temperatures, and moisture levels in order to germinate successfully. In the Seed Germination Gizmo, you will perform a series of experiments to determine the best conditions for germinating three different types of seeds. 1. Look at the DESCRIPTION tab. How many seeds are in the germination chamber? 100 2. Click Play ( ), and observe the SIMULATION pane. A. What happened over the simulated five-day period? While some seeds failed to germinate, others did B. How does the appearance of a seed on the SIMULATION pane change once the seed hassprouted? When it grows, a yellow,upward-pointing object thatresembles a vine appears fromthe seed. C. How many seeds sprouted? 55 D. How many seeds did not sprout? 45 Reproduction for educational use only. Public sharing or posting prohibited. © 2020 ExploreLearning™ All rights reserved
Activity A: Repeating Trials Get the Gizmo ready: ● Click Reset ( ). ● Select the BAR CHART tab and turn on Show numerical values . Question: Why is it important to repeat an experiment multiple times? 1. Collect data: Each time you run an experiment with the Gizmo, you complete a trial. A trial is a single time that you conduct an experiment. Make sure Seed type: A is selected on the SIMULATION pane. The Water level should be set to 50 drops per hour. The Light should be at 50%, and the Temp. should be 18 °C. At these settings, click Play to run the Gizmo and complete the first trial. Record your results in the first row of the table below. Then, use theGizmo to run two more trials. Trial Number of seeds Number of sprouts 1 48 52 2 50 50 3 47 53 Mean 48.3 51.7 2. Calculate: Find the mean , or average, for each trial. Add the number of seeds from each trial together. Then, divide the sum by 3. Record the result in the table, and then repeat the calculation for the number ofsprouts from each trial. 3. Compare: How do the results from the three trials compare? There isn't a significant difference in the values between the three trials when we comparethem. 4. Infer: What do you think caused the differences between the results of each trial? Some of the seedlings did not receive the required nutrition and sunlight, which caused thevariances. On other experiments, a few seeds received more nutrients, and the variationswere brought on by sunlight. 5. Draw conclusions: Use the data you collected to explain why it is important to repeat an experiment multiple times. It is essential to repeat the steps over time because that way you can collect some moreevidence, and don’t jump right into a conclusion. Reproduction for educational use only. Public sharing or posting prohibited. © 2020 ExploreLearning™ All rights reserved
Activity B: Variables Get the Gizmo ready: ● Click Reset . Make sure Seed type: A is selected. Question: In what conditions will seed A have the highest germination rate? 1. Collect data: Use the Water , Light , and Temp. sliders on the SIMULATION pane to set up each scenario listed in the table below. Complete three trials for each scenario and record your results in the table. Then,calculate the mean of the three trials for the last column. Water (drops/hr) Light Temp. Number of sprouts Mean number of sprouts Trial 1 Trial 2 Trial 3 30 15% 10 °C 28 27 30 28.3 60 45% 20 °C 55 63 60 59.3 90 80% 30 °C 76 77 77 76.7 2. Analyze: Use the data you collected to answer the questions below. A. Which scenario had the highest germination rate? Sanario 3 B. A variable is something that can be changed in an experiment. In the experiments you just performed, you changed the water, light, and temperature. Can you tell which of these variablesaffected the germination rate? Explain your answer. No, I can't. If I could modify each of these variables individually to see the germinationrate, that is. C. A controlled experiment is an experiment in which only one variable is changed at a time. Why is it important to do a controlled experiment in order to determine how a variable, such as water, light,or temperature, affects seed germination rates? It is crucial to adjust just one variable at a time so that we can observe how it influencesthe outcomes. 3. Form a hypothesis: A hypothesis is a proposed explanation for an observation. Write a hypothesis about what conditions would be best for germinating seed A. The ideal conditions for seed A to germinate would be 90 drops of water per hour, 80% light,and 30 degrees of temperature. Reproduction for educational use only. Public sharing or posting prohibited. © 2020 ExploreLearning™ All rights reserved
4. Experiment: You will now run a set of controlled experiments to test each variable separately. Complete three trials for each scenario in the tables below. Record your results. Water (drops/hr) Light Temp. Number of sprouts Mean number of sprouts Trial 1 Trial 2 Trial 3 50 50% 5 °C 0 0 0 0 50 50% 15 °C 49 46 46 48 50 50% 25 °C 61 61 64 62 50 50% 35 °C 57 50 59 55.3 Water (drops/hr) Light Temp. Number of sprouts Mean number of sprouts Trial 1 Trial 2 Trial 3 50 0% 18 °C 52 49 50 50.3 50 50% 18 °C 51 49 54 51.3 50 100% 18 °C 49 51 50 50 Water (drops/hr) Light Temp. Number of sprouts Mean number of sprouts Trial 1 Trial 2 Trial 3 0 50% 18 °C 0 0 0 0 50 50% 18 °C 52 52 52 52 100 50% 18 °C 0 55 60 38.3 5. Analyze: Describe the effect of each variable on seed A’s germination rate. The rate of germination would rise if we raised the temperature by 10 degrees. The rate ofgermination is not significantly affected by increasing light levels. It would have a low rate ofgermination if we provided too little or too much water. 6. Challenge yourself: Experiment to find the best combination of water amount, light level, and temperature at which to germinate the most seeds of seed type A. A. Which conditions yielded the highest germination rate? The best rate of germination would be at 25 C, 50% light,and 80 drops of water eachhour. B. What type of habitat do you think seed A would grow best in? Explain your answer. Tropical rainforests Reproduction for educational use only. Public sharing or posting prohibited. © 2020 ExploreLearning™ All rights reserved
Activity C: Experimentaldesign Get the Gizmo ready: ● Click Reset . ● Select Seed type: B . Question: In what conditions will seed B and seed C have the highest germination rate? 1. Observe: Run two experiments with seed B. What did you observe? I saw that the biggest impact on the rate of germination would come from changing thewater. 2. Form a hypothesis: What conditions do you think will be ideal for germinating seed B? A high water content, warm temperature, and moderate amount of light would be optimalconditions for germination. 3. Draw conclusions: What conditions gave the best germination rate for seed B? A high water drop rate per hour, medium light levels, and low temperatures would result inthe ideal germination rate for seed B. 4. Compare: Study the results of your experiments with seed A and seed B. A. Which variable(s) affected seed B that did not affect seed A? While seed A was unaffected, seed Bwas affected by the light. B. Based on this fact, do you think seed B is normally planted deep below the soil or nearthe surface? Shallow hole, as the seed would receivemore light if it were put close to thesurface. 5. Observe: Run two experiments with seed C. What did you observe? I observe that if we change the value of light then it would have the biggest effect ongermination rate. 6. Form a hypothesis: What conditions do you think will be ideal for germinating seed C? The best rate of germination for see C is when there is a medium amount of water, a lot oflight, and a cool environment. 7. Draw conclusions: What conditions gave the best germination rate for seed C? Reproduction for educational use only. Public sharing or posting prohibited. © 2020 ExploreLearning™ All rights reserved
The ideal germination rate for seed C would be 50 drops of water per hour, 20% light, and20% temperature. 8. Interpret: What type of habitats do you think seed B and seed C would grow best in? Seed B: Tropical rainforest Seed C: Forest Reproduction for educational use only. Public sharing or posting prohibited. © 2020 ExploreLearning™ All rights reserved
