Contents
How do you do the onion cell experiment?
Making slides
- Peel a thin, transparent layer of epidermal cells from the inside of an onion.
- Place cells on a microscope slide.
- Add a drop of water or iodine (a chemical stain).
- Lower a coverslip onto the onion cells using forceps or a mounted needle. This needs to be done gently to prevent trapping air bubbles.
How do onion cells look under the microscope?
Tissue from an onion is a good first exercise in using the microscope and viewing plant cells. The cells are easily visible under a microscope and the preparation of a thin section is straight forward. An onion is made of layers, each separated by a thin skin or membrane.
What type of cell is an onion cell?
They are the prokaryotic cells. They do not have organelles bounded with membrane as they do not have a complex body. They even lack membrane around the nucleus. Onion cell is a eukaryotic cell with well-defined membranes around the organelles.
Do onion cells have mitochondria?
Both plant cells and animal cells contain mitochondria and yet they were not visible in the cells you viewed. These cells are eukaryotic . This means they have a nucleus and other structures which are surrounded by membranes .
What parts of onion cell can you identify?
Onion Cell The nucleus is present at the periphery of the cytoplasm. The vacuole is prominent and present at the centre of the cell. It is surrounded by cytoplasm. The presence of a cell wall and a large vacuole are indicators that help identify plant cells, such as seen in the onion peel.
What type of cell is the onion cell?
The onion cell is a plant cell that can be obtained by peeling off an onion. Onion cells exhibit a brick-like shape under the microscope. It has a cell wall, cell membrane, cytoplasm, nucleus, and a large vacuole. At the periphery of the cytoplasm, the nucleus is present.
What is the function of the onion cell?
The epidermal cells of onions provide a protective layer against viruses and fungi that may harm the sensitive tissues. Because of their simple structure and transparency they are often used to introduce students to plant anatomy or to demonstrate plasmolysis.
What is specialized structure of onion?
The onion plant has a fan of hollow, bluish-green leaves and its bulb at the base of the plant begins to swell when a certain day-length is reached. The bulbs are composed of shortened, compressed, underground stems surrounded by fleshy modified scale (leaves) that envelop a central bud at the tip of the stem.
Why is onion used in plant tissue experiment?
Onions are used because they have large cells that are easily visible under a microscope and the preparation of a thin section is very straight forward. More competent and experience technicians maybe called upon to help support the classroom teacher during this practical. Herein, why onion is used in plant tissue experiment?
What can you learn about onion cells under a microscope?
Having observed the onion cell under the microscope, students will be able to learn the differences between animal and plant cells in addition to the function of the different parts of the cell.
Why is iodine stain used on onion cells?
The epidermal cells of onions provide a protective layer against viruses and fungi that may harm the sensitive tissues. Because of their simple structure and transparency they are often used to introduce students to plant anatomy or to demonstrate plasmolysis. Additionally, why is iodine stain used on onion cells?
Why is onion root tip used to demonstrate mitosis in this experiment?
Why is onion root tip used to demonstrate mitosis in this experiment? It is because of the meristematic cells that are situated in the tip of the roots that render the most desirable and suitable raw material to study the different stages of mitosis. Onion is a monocot plant.