Observe the slide under both low and high power magnification, 6. Place a flat piece of this membrane on a glass slide. They have a different function than leaves bulbs are an emergency energy storage organ, whereas leaves convert solar energy to glucose for immediate use by the plant 3.
Which represents cells in pure water? For elementary school kids, teacher should handle the stain as it is a potential skin toxin. Adjust focus for clarity to observe. Lab 1A — The data collected in this lab experiment did not seem to contain any inconsistencies, so therefore no human error is detected.
Observe the slide with both low power and high power magnification. This can be stated because the cores took in water while they were emerged in the distilled water. Why can onion bulbs be considered a separate plant organ?
Show them an onion bulb and ask if they know its function or its anatomical role for the plant.
Were the cells you observed the product of mitosis or meiosis? This is because they have a cell wall made up of cellulose which maintains its shape.
There is only 1 type of cell present. Answers will vary depending on how much cell biology has been covered prior to the experiment. Although onions are plants, students will not see any chloroplasts in their slides.
Estimate the length in microns of the cells, as seen under high power. Why would you expect iodine to be more effective in onion bulbs than in roots or leaves? Lab 1C provided information that helps to conclude that potatoes do contain sucrose molecules. Can you identify structures that were likely present in the cells that might have been visible at higher magnification?
In plant and animal cells, loss or gain of water can have different effects.
Going Further Once students have mastered the above procedure, advanced students should be able to design and carry out similar investigations using yellow or white onion iodine can be used to stain the cells, as it binds to the starch granules in the cytoplasm and nucleus or other plant cells for comparison.The purpose of this lab is to compare the three different types of solutions affect on the relative size of the vacuole to the cell, the outer membrane of onion red cells (tunics) are used to figure out the different types.
Biology, Answering the Big Questions of Life/Osmosis lab. From Wikibooks, open books for an open world In this lab we will observe plasmolysis in red onion cells. Instructions: Draw the image and label this cell AFTER. Explain what happened to the cells. Alternative Instructions.
Procedure: A. Prepare a wet mount slide of onion skin cells as directed by your teacher. You will be given a piece of onion. Requirements, Preparation and Observation. The bulb of an onion is formed from modified leaves. While photosynthesis takes place in the leaves of an onion containing chloroplast, the little glucose that is produced from this process is converted in to starch (starch granules) and stored in the bulb.
Having observed the onion cell under the. If the onion cell experiment in part 1E of the lab would have produced correct results, conclusions could have been made. It is thought that the onion cells would have plasmolyzed due to the addition of NaCl to the cells.
Each lab team should have 1 microscope, glass slides, 1 forceps or tweezers, and a segment of red onion. If students will be staining specimens themselves, you can aliquot the stains into dropper bottles (1 per student team).Download