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What is the result of the Test for the presence of starch in a leaf?
Wiki User
∙ 14y ago
Method
Half fill a beaker with boiling water and add a large test tube that is a
quarter full of ethanol. Allow the ethanol to come to the boil. Do not heat
the ethanol in a Bunsen burner flame. This is not safe because ethanol is
highly flammable.
Take a leaf that has been sitting in good light for at least a few days, and
soften on the boiling water for ten seconds or so. Then add to the ethanol
and allow to boil for about a minute until all the colour disappears from
the leaf.
Remove the leaf from the ethanol. Put it back in the hot water to soften for
10 seconds.
Spread the leaf out on a white tile and use the iodine solution to test for
starch A blue-black colour indicates starch is present.
This experiment can be repeated with leaves that have been left in the dark.
or have been deprived of carbon dioxide.
Wiki User
∙ 12y ago
Wiki User
∙ 13y ago1. Put the leaf you want into a beaker of boiling water for about 10 seconds.
2. Then put your leaf into a test tube of ethanol and place back into the boiling water for about 10 minutes. BE CAREFUL ETHANOL IS A HIGHLY FLAMMABLE SUBSTANCE AND IF YOU ARE USING A BUNSEN BURNER TO HEAT THE WATER MAKE SURE THAT THE BUNSEN IS OUT WHEN YOU PLACE THE ETHANOL INTO THE BOILING WATER!!
3. Take the leaf out of the ethanol and wave the leaf around to and fro in the boiling water, (this will remove the ethanol from the leaf).
4. Place the leaf in a petri dish and cover the leaf in dilute iodine. The starch in the leaf will show up a blue-brown.
Wiki User
∙ 14y agoPlease rephrase your question.
If I would have to answer this particular question, the answer would be: Positive.
There is starch in a leaf, unless you extract it by use of an anorganic substance*
*please edit this part
Wiki User
∙ 13y agoTake a leaf and boil it in a test tube filled with . This is done to kill the cell. The chlorophyll doesn't dissolve in water though.
Then put the leaf inside a test tube filled with alcohol. Place the test tube in a water bath over a Bunsen burner and boil the bath. This is done as a precaution because alcohol is highly inflammable.
When the alcohol turns green, then that means that the chlorophyll has come out of the leave. The leaf will turn white. Chlorophyll only dissolves in alcohol.
Take the leaf and rinse it under water as the leaf becomes very brittle on heating.
The leaf softens.
Take a white tile and place the leaf on it. Drop a few drops of iodine solution on the leaf. You will see it turn blue-black which means starch is present in the leaf.
Wiki User
∙ 13y agoGreen plants contain a green plastid called cholorophyll that help in the production of starch by process of photosynthesis.
1. A peel of the green plant is dipped in hot water and rinsed in ethanol solution.
2.The peel is rinsed in hot water and kept in a dish with iodine solution.
3 The peel will appear blue/brown to show the presence of starch.
Wiki User
∙ 15y agoIodine solution is used to test the presence of starch. we can know this as it changes its colour to blue-black.
Wiki User
∙ 15y agoThe presence of starch in a leaf indicates that photosynthesis has occurred.
Wiki User
∙ 14y agoTry Potassium Iodine-Iodide (KI3) solution testing on starch will turn it blue-purple
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A chemical solution used to test starch is?
the answer to tis would be iodine because it is uses in the method to test for presence of startch in a leaf
What is the purpose of detecting the presence of starch in leaf?
It can be used to prove that photosynthesis has happened.
What happens if starch is present in leaf?
The presence of starch in plants indicate that photosynthesis has occurred. The process of testing the presence of starch uses iodine solution that turns to blue-black on a positive test.
Why did the leaf turn brittle in testing a leaf for starch?
The leaf turns brittle during the testing the leaf for starch because the ethanol extracts the all water content from the leaf.
When testing a leaf for starch why do you have to boil the leaf in water first?
so the waxy cuticles can rub off the surface of the leaf. a leaf has a cell wall and if you did not put the leaf in the boiling water it would not break down so therefore you would not be able to do a proper starch test on the leaf so the answer to this question is to break the cell wall down so you can test for starch properly i hope i helped you :) yeap
What happened a non green leaf is tested for starch?
A non-green leaf lacking chloroplasts will not be able to synthesize food which later on gets converted into starch. So it will not show the presence of starch in the test.
A chemical solution used to test starch is?
the answer to tis would be iodine because it is uses in the method to test for presence of startch in a leaf
Result of starch test on variegated leaves?
the leaf that contains starch will turn blue/black if not it will stay the same colour
What would be the conclusion after testing a leaf for starch?
Starch is produced by leaves during Photosynthesis, therefore if the leaf has not been exposed to light then it will not contain starch, and so when tested the Iodine will stay Yellow/Brown. Consequently if the leaf has been left in the light Photosynthesis will have taken place and when tested the Iodine will go Blue/Black showing that Starch is present. Hope this helps :)
What did you see on the leaf in the test tube when testing for starch?
Use iodine to test a leaf for starch | Plant Physiology | Biology
Do the non -green areas of a leaf contain starch?
kritika chauhan- no. you can imitate a test .put 10 drops of dilute iodine solution on it. if it turns blue black than it contains starch. a blue black color indicate presence of starch in a food item. if you will do this test for a non green leaf it will be negative.
Why is the color of leaf became dark blue after using the iodine solution is that means the leaf is healthy and have more starch?
because of the presence of starch
Why did the leaf turn blue black when iodine was added in the starch test?
because photosynthesis has occured in the leaf. starch is produced and turns iodine blue-black indicating the presence of starch.
Why you use iodine to test the presence of starch but why not other chemicals?
Because it call sense the difference between a base and an acid.
How do you test a leaf of starch?
The test of starch by covering the black paper and keeping it into a light place at few hours.
What is the purpose of detecting the presence of starch in leaf?
It can be used to prove that photosynthesis has happened.
What happens if starch is present in leaf?
The presence of starch in plants indicate that photosynthesis has occurred. The process of testing the presence of starch uses iodine solution that turns to blue-black on a positive test.
