Cells present in onion peel can be observed
under microscope. For this onion peels are first isolated. For this experiment outer
most scale of the onion is removed and is cut into four equal halves. It is a
monocot plant. Then with the help of a pairs of forcep the scale of onion is
peeled out. It should be fleshy unless in the dried ones experiment cannot be
done due to the absence of proper cellular structure. Then the onion peel is
sized into 5mm × 5mm size (approx). A slide should be properly cleaned and keep
it for the preparation of the onion peel.
Then the part of the onion peel is placed on the slide and a previously cleaned cover slip is placed on the part of the peel. During the placement of cover slip precautions should be taken that there should not be present of air bubbles. It is stained with iodine solutions or eosin solutions. Eosins are responsible for staining of nucleus as it is acidic in nature. After adding of stain by the help of dropper excess stain should be removed by washing. Then the prepared slide can be observed under microscope.
Observation under Microscope - Cells are appeared to be prominent, individual, linear, rectangular in shape. If it is observed under electron microscope in low resolution then the presence of cell wall and nucleus are observed. But if it is observed under microscope in high resolution then presence of cell vacuoles can be observed properly.
Characteristics features of the onion peels are -
1. Cells are firmly bound to each other.
2. Nucleus present in the cells are slightly towards the periphery of the cells. Which is the one of the confirmation point of onion peel.