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Effect of sunlight (environment) on phenotype... (1 Viewer)

danz90

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I have almost finished my practical where I had fast-growing radish seeds germinating in cotton wool in a petri dish. I placed one inside a completely dark place, and the other in an area exposed to sunlight.

My results showed that the one in the dark grew MUCH faster and higher than the one in the sunlight, however is very unsturdy and is falling down now. For example, after 8 days, the ones in darkness are about 8cm tall, while the ones in sunlight are 2cm tall.

The explanation for this would be that even though some seeds that grew tall have dominant genes for tallness, the phenotype for tallness was expressed better in the ones in sunlight (as the sturdy stems are created using starch/glucose obtained via photosynthesis - this is not possible in the one in the dark, which initially grew much faster and higher than the ones in the light, because they had a slightly warmer temperature (being in a closed cupboard), thus promoting initial faster growth.

Is this correct?

Would appreciate any help. :)
 

white ferret

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the one in the dark grew very tall because it's trying to reach sunlight [bascially, it 'thinks' it's on the bottom of the rainforest floor and it's trying to grow past the tall foliage of tree leaves to reach sunlight]..

but yeahh.. it's bascially right
 

sharkboy

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I have almost finished my practical where I had fast-growing radish seeds germinating in cotton wool in a petri dish. I placed one inside a completely dark place, and the other in an area exposed to sunlight.

My results showed that the one in the dark grew MUCH faster and higher than the one in the sunlight, however is very unsturdy and is falling down now. For example, after 8 days, the ones in darkness are about 8cm tall, while the ones in sunlight are 2cm tall.

The explanation for this would be that even though some seeds that grew tall have dominant genes for tallness, the phenotype for tallness was expressed better in the ones in sunlight (as the sturdy stems are created using starch/glucose obtained via photosynthesis - this is not possible in the one in the dark, which initially grew much faster and higher than the ones in the light, because they had a slightly warmer temperature (being in a closed cupboard), thus promoting initial faster growth.

Is this correct?

Would appreciate any help. :)
mate is it ok if you can lend me that experiment? cause i need to customize one of the net and i cant find any like yours! :(

my email is the_rock_of_evan@hotmail.com

thank you
 

watsthebuzz

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I have almost finished my practical where I had fast-growing radish seeds germinating in cotton wool in a petri dish. I placed one inside a completely dark place, and the other in an area exposed to sunlight.

My results showed that the one in the dark grew MUCH faster and higher than the one in the sunlight, however is very unsturdy and is falling down now. For example, after 8 days, the ones in darkness are about 8cm tall, while the ones in sunlight are 2cm tall.

The explanation for this would be that even though some seeds that grew tall have dominant genes for tallness, the phenotype for tallness was expressed better in the ones in sunlight (as the sturdy stems are created using starch/glucose obtained via photosynthesis - this is not possible in the one in the dark, which initially grew much faster and higher than the ones in the light, because they had a slightly warmer temperature (being in a closed cupboard), thus promoting initial faster growth.

Is this correct?

Would appreciate any help. :)
Hi, did you keep all the variables constant, such as the amount of water you gace to each?? This could be one of the improvements/recommendations you could make in your discussion, to improve your experiment. Also the plant in the dark doesn't grow faster because it has a 'tall gene". It's actually controlled by chemical signals released by the plants in the dark. These chemical signals, stop the leaves from becoming large(no light, so why waste energy trying to make things which harvest light, right?) and instead grow towards or taller trying to reach light. This chemical signal is called auxin (IAA-Indole Acetic Acid).
Here is a website with more information. http://www.cartage.org.lb/en/themes...treproduction/PlantBehavior/PlantBehavior.htm

Hope that help, and let me know if you have any other questions.
 

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