Gas bubbles from the pond weed Testing hypotheses in scientific investigation Observation Bubbles coming out from the pond weed. These are oxygen bubbles produced by the plants during photosynthesis. Betsy was not convinced of this explanation.
Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.
Testing hypotheses in
Bubbles coming out from the pond weed.
of this explanation.
They could have been produced by respiration or other life processes.
What are the gas bubbles made up of ?
Green plants undergo photosynthesis in the presence of light to produce energy-rich food.
You eat a banana & find that it has no seed inside.
After eating a second, third, & ... tenth banana, you also find them seedless.
1. Banana plants do not have flowers.
2. Banana flowers do not produce pollen grains.
3. No fertilization takes place in the banana flower.
The sun has risen in the east every day in the past years.
The sun always rises
in the east.
The sun will rise in the east tomorrow.
Why does the sun rise in the east?
1. The sun moves around the earth.
2. The earth rotates on its axis from west to east.
Betsy’s next step:
Which alternative explanations (hypotheses) was the best answer to the question?
Ifthe gas is carbon dioxide produced by respiration of the pond weed…..
then the pond weed will produce the gas all the time.
then the gas will turn lime water milky.
If the gas is oxygen produced by photosynthesis of the pond weed …..
then the pond weed will only produce the gas in the presence of light.
thenthe gas will not turn lime water milky, but will be absorbed by alkaline pyrogallic solution.
The gas bubbles are made up of oxygen produced by the pond weed during photosynthesis.
Green bananas taste flat but become yellow & taste sweet after storing for a few days.
The green banana carries out photosynthesis to produce sugar during storage.
The starch in the raw banana changes into sugar during storage.
What is the optimum temperature of salivary amylase?
Which area of the hand is most sensitive to touch, heat, cold or pressure?