Today’s Key Questions:

1. How did the completion of my cell model help me understand a cell?
2. What will an onion cell look like after the onion has been cut open for a few days?

By the end of class, I should be able to:

• complete an assessment about cell components
• reflect on what I have learned and still need to work on
• find and draw an onion cell

Language Goals:

• write a blog post that describes what I observed.

September Process Words

• Investigate
• Produce
• Demonstrate (7th)
• Emphasize (7th)

Onion skin cells Add 2 drops of iodine to the center of a glass slide. Be careful! Iodine can stain your clothes. Take a small piece of onion. Use tweezers to peel off the skin from the underside (the rough, white side) of the onion. Throw the rest of the onion piece away. Carefully lay the onion skin flat in the center of the slide on top of the iodine. Add 2 drops of iodine to the top of the onion skin. Stand a thin glass cover slip on its edge near the onion skin, next to the drop of iodine. Slowly lower the other side of the cover slip until it covers the onion skin completely. If there are air bubbles, gently tap on the glass to “chase” them out.

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2 drops iodine onion skin 2 drops iodine glass slide

Make at least one (1) drawing of the onion cells using the best magnification you can achieve.

Plant vs Animal Cell Blog Post - Your writing will support the drawings that you have produced.

A few weeks ago, you investigated the cells in your mouth and drew a cell from your cheek. Today, you found an onion cell. Please include both drawings on this post and then write to compare the cells. In your writing, you should describe what you saw in each occasion, describe items that are similar and those that are different.