Table of Contents
- 1 What does the presence of blue black color in leaf after covering it with iodine indicate?
- 2 Why does the white patches in the variegated leaf do not turn blue black?
- 3 Why does the green part of variegated leaf turns blue black after putting in iodine solution?
- 4 Which part the leaf turns blue black What about the remaining part?
- 5 Why do we boil leaf in alcohol?
- 6 Why does alcohol remove chlorophyll?
- 7 What part of the leaf does not turn into blue black color?
- 8 Why are plants kept in dark for 3 days?
- 9 What makes a leaf turn blue in the presence of starch?
- 10 Why is a variegated leaf used to show chlorophyll?
- 11 Why does a variegated leaf have green parts?
What does the presence of blue black color in leaf after covering it with iodine indicate?
Iodine is an indicator that turns blue-black in the presence of starch. The leaf that was in the light turns blue-black, which demonstrates that the leaf has been performing photosynthesis and producing starch.
Why does the white patches in the variegated leaf do not turn blue black?
The leaf on the left is a variegated leaf. The green parts contain chlorophyll and photosynthesise to make starch. The white part of the leaf does not contain chlorophyll, so does not photosynthesise. Only the uncovered parts become blue/black with iodine solution, showing the importance of light in photosynthesis.
What does the variegated leaf experiment of photosynthesis prove?
The variegated leaf experiment helps to exhibit that chlorophyll (pigment present in the green parts of plants) is necessary for photosynthesis. This, in turn, proves that photosynthesis happened. The white areas of the leaf in absence of chlorophyll could not photosynthesize.
Why does the green part of variegated leaf turns blue black after putting in iodine solution?
-The green parts of the variegated leaf have chlorophyll in it. Only those sections may thus carry out photosynthesis and generate food (starch). Starch reacts with iodine in the presence of iodine and gives it a blue-black color.
Which part the leaf turns blue black What about the remaining part?
when we put iodine solution onto the leaf, the part where the starch is present changes into blue-black colour. the part where the iodine solution is not put remains unchanged colour.
Which part of the leaf turns into deep blue Colour?
The part which turns blue black shows the presence of starch while the part which does not have starch shows brown colouration. In the experiment to prove that a plant contains starch or not, First, destarch the plant by keeping in a dark room for 24 – 48 hours.
Why do we boil leaf in alcohol?
We boil the leaf in alcohol when we are checking it for starch to eradicate chlorophyll, which is the green pigment present in leaves. Hence to dissolve the chlorophyll or the green pigment present in the leaf we boil the leaf in alcohol when we are testing it for starch.
Why does alcohol remove chlorophyll?
Do you know why chlorophyll can be removed from the leaf by ethanol? Ethanol is an organic solvent that causes the plant cells to become leaky. The chlorophyll inside the cells become available and dissolves in the ethanol.
What part of the leaf turns into blue black color?
The part of leaf that contains starch will turn blue black. The iodine test is done to determine the presence of starch in a solution or cell. The iodine reacts with the starch to give blue black color which is indicative of formation of starch-iodine complex.
What part of the leaf does not turn into blue black color?
when we put iodine solution onto the leaf, the part where the starch is present changes into blue-black colour. the part where the iodine solution is not put remains unchanged colour. even if the part where iodine is present does not change blue-black colour ,it means that , there is no presence of starch.
Why are plants kept in dark for 3 days?
This is because, since it was kept in a dark room where there was no sunlight, the plant was unable to prepare the food by photosynthesis. And starch is the product of photosynthesis.
Which part of the leaf turns into blue Colour?
Answer: The part of leaf that contains starch will turn blue black. The photosynthesis occurs in the leaves during the day when the chlorophyll pigment absorbs the light energy from the sun to produce food in the form of carbohydrate.
What makes a leaf turn blue in the presence of starch?
Iodine is an indicator that turns blue-black in the presence of starch. The leaf that was in the light turns blue-black, which demonstrates that the leaf has been performing photosynthesis and producing starch.
Why is a variegated leaf used to show chlorophyll?
The variegated leaf experiment helps to exhibit that chlorophyll (pigment present in the green parts of plants) is necessary for photosynthesis. Parts of the leaf with the chlorophyll should turn blue-black when iodine is added showing the starch is present. This, in turn, proves that photosynthesis happened.
Where does photosynthesis occur in a variegated leaf experiment?
On testing these leaves for starch it was clear that photosynthesis occurred only in the green parts of the leaves in the presence of light. So, the correct option is ‘Chlorophyll’. Was this answer helpful?
Why does a variegated leaf have green parts?
A variegated leaf is a leaf with green and non-green parts. The green parts of the leaf photosynthesise because they contain chlorophyll. Total absence of plastid pigments causes a sector of a leaf or stem to have white patches.