How can a plant be destarched and why is it important to do this before investigating photosynthesis?
Before carrying out investigations into photosynthesis, it is usually necessary to destarch the plant. This involves leaving the plant in darkness (e.g. a dark cupboard) for 48 hours. This is necessary to make sure that any starch produced is only produced during the investigation.
What does it mean to destarch a plant?
Destarching occurs in a plant when a part of a plant is “deprived of starch, as by translocation”. This is done by leaving the plant(s) in a dark place for a long period of time. Due to the lack of photosynthesis in this place, stored starch is used up, thus the plant is destarched.
Why do we destarch a potted plant?
a) If a potted plant is kept in darkness for 48 hours, all starch in its leaves should have been changed to sugars and conducted out of the leaves. This is destarching. (b) To check on the destarching, single of the leaves or part of a leaf should be tested with iodine to make sure the leaf is free from starch.
When and why should we destarch a plant?
Answer : It is important to destarch a plant before performing any experiment on photosynthesis so that it can be established whether or not a particular factor (carbon dioxide/ light/ water) is important for the photosynthetic reaction.
Why do plants grow faster at night?
The absence of light actually stimulates plants to grow fastest at night. Plant phytochromes detect darkness, encouraging growth hormone production, causing the plant to elongate in search of light. The same process helps plants orientate their foliage to light and helps seedlings stretch in search of light.
Why is it important to destarch a plant before performing an experiment?
A plant is destarched before performing any experiment in order to prevent photosynthesis. If starch is already present then it will create hindrance in determining the correct pathway of photosynthesis which results in the formation of food. Destarching is done by keeping the plant in absence of sunlight so that the stored starch is used up,…
How long does it take to destarch a plant?
Destarching a plant: Before carrying out any photosynthesis practical it is necessary to destarch the plant by placing it in the dark for at least 48 hours. During this time any starch will be removed or used. This step is important so you can be positive that any starch present at the end of the experiment has been produced during the experiment.
Why is it necessary to de starch a plant?
De-starching is the process by which the starch reserves in a plant are depleted by depriving the plant of either light or carbon dioxide. Why is it necessary to de-starch the leaves of a plant before conducting photosynthesis experiments?
How can you tell if a plant has fully destarched?
This step is important so you can be positive that any starch present at the end of the experiment has been produced during the experiment. You can check if a plant has been fully destarched by testing a leaf for starch. If the iodine remains yellow-brown, all the starch has successfully been removed.