Practical 14.2 Design an investigation of other conditions for seed germination

Oxford Mastering Biology 牛津基礎生物學

4 Jan 202102:00

Summary

TLDRThis video demonstrates a simple experiment to explore the effects of water, temperature, and light on mung bean germination. Four tubes labeled A to D are prepared with mung beans and cotton wool. Tubes B and D receive water, while C gets boiled water and a layer of paraffin oil. Tube B is refrigerated, and A, C, and D are kept in a light-proof box in a warm place. After two to three days, the number of germinated beans is counted, and germination percentages are calculated to draw conclusions about the environmental factors influencing germination.

Takeaways

🌱 Experiment involves mung beans in boiling tubes labeled A to D.
🔬 Dry cotton wool is used as a substrate in each tube.
💧 Water is added to tubes B and D to cover the mung beans.
🥣 Boiled water is used in tube C with an added layer of paraffin oil.
🧊 Tube B is placed in a refrigerator to test the effect of cold temperature.
🌡 Tubes A, C, and D are kept in a warm place to observe germination.
🕒 The experiment duration is two to three days.
🌞 A lightproof box is used to cover tubes A, C, and D to control light exposure.
📊 Germination rates are measured and calculated as percentages.
📝 Results are recorded for analysis.

Q & A

What is the purpose of using four boiling tubes labeled A to D in the experiment?
-The purpose is to create different conditions to observe the effects of these conditions on the germination of mung beans.
Why is dry cotton wool placed in each boiling tube?
-Dry cotton wool is used to provide a surface for the mung beans to rest on and to absorb excess water, preventing the beans from floating.
How many mung beans are placed in each boiling tube?
-10 mung beans are placed into each boiling tube.
What is the significance of adding water to boiling tubes B and D?
-Adding water to B and D creates a moist environment necessary for the mung beans to germinate.
Why is boiled water added to boiling tube C instead of regular water?
-Boiled water is used to prevent the growth of bacteria or other microorganisms that might be present in unboiled water.
What is the role of the paraffin oil layer in boiling tube C?
-The paraffin oil layer prevents oxygen from reaching the mung beans, simulating an anaerobic condition to test its effect on germination.
Why is boiling tube B placed in a refrigerator?
-Placing tube B in a refrigerator creates a cold environment to test the effect of temperature on the germination of mung beans.
What does covering tubes A, C, and D with a lightproof box achieve?
-A lightproof box covers tubes A, C, and D to create a dark environment, testing the effect of light on germination.
How long are the tubes left in a warm place before counting the germinated mung beans?
-The tubes are left in a warm place for two to three days before counting the germinated mung beans.
What is the final step in the experiment after the germination period?
-The final step is to count the number of germinated mung beans and calculate the percentage of germination in each tube.
Why is it important to record the results of the germination experiment?
-Recording the results allows for comparison between the different conditions and helps to draw conclusions about the factors affecting mung bean germination.