Onion Cell

1. Cheek Cell Onion Cell Plant and Animal Cell Lab

2. Under Period on Lab Sheet write: Microscope #: __________ One of the first scientists to look at cells under a microscope was an English scientist by the name of Robert Hooke. He viewed and described the appearance of cork under the microscope and decided to name the tiny box-like structures that he observed “cells” because they looked like the small chambers where monks lived.

3. By the early part of the 19th century, it was accepted that all living things are composed of cells. Cells come in a variety of shapes and sizes, and cells perform different functions. Although cells may appear outwardly different, they resemble each other because they share common structures. In this lab you will look at two types of cells, a human cheek cell and an onion cell and see how they are similar and how they are different.

4. Place the layer of tissue on a slide and then add a small drop of iodine to the slide. • Remember to only use the fine adjustment to • focus at higher powers. • Draw one or two onion cells in detail on the highest power (careful not to crack the slide) on the attached page. • Provide the name of the object and the power under which it was observed • Pg 186 to answer questions

5. What order of objective lens is used? Use the low power to locate and focus the cells Then switch to High Power to view and draw the cell

6. What order do you follow to make the onion slide? Put a layer of onion on slide Put a drop of Iodine on slide Slowly put the cover slip over the top. What order do you follow to make the cheek slide? Use a toothpick to gently scrape cheek Smear the toothpick on the slide and discard Put a drop of methlyene blue on the slide. Slowly put the cover slip over the top.

7. Lab Clean up Wrap Cord around base of microscope Bag Microscope Clean and return slide and cover slip to me Make sure that lab station is dry and clean