You may be one person, but you're made up of millions and billions of cells! Have you ever thought about all the tiny, microscopic cells that make up you? While your cells are much too small to see without a microscope, there are ways to create the look of a cell in your very own home without fancy equipment. In fact, everything you need is right in your kitchen.
What does a cell look like?
- Large eggs
- 2 jars
- 2 cups white vinegar
- Begin by studying your egg. What do you notice? Is it possible to see anything besides the hard, white shell?
- Take out your notebook. Think about what a cell might look like and make a sketch.
- Write down, in words, your guess at what a cell looks like? This kind of guess is often called a hypothesis.
- Now pour white vinegar into the jar.
- Gently place your egg in the vinegar. (Note: You may want to try to experiment with more than one egg. If the egg breaks, it will be nice to have a back-up!)
- Write down anything you notice about the egg as soon as it is covered by the vinegar.
- Wait ten minutes before checking the egg again. Now what does it look like?
- Over the next three days, come back and check on your egg. Remember to always write down your observations.
- After three days have passed, carefully take out your egg. Roll it around in your hands. What does it feel like?
- When you're done playing with your egg, take it outside. Gently use your finger to poke the egg's soft outer layer. What do you see?
- With this experiment, the parts of the egg mimic three important parts of a cell: the membrane, the nucleus and the cytoplasm. Can you identify what's what in your naked egg? Was your hypothesis correct?
The white shell dissolved in the vinegar, revealing a squishy, translucent, or semi-transparent, inside. The egg should have expanded during the three days in the vinegar bath, and the yolk should have spilled out when you poked your finger into the egg.
It's amazing that eggs look a lot like cells. The translucent egg covering beneath the dissolved shell acts the same as a cell's membrane, the squishy boundary that holds the cell together. The yolk acted as the cell's nucleus, and the rest of the liquid was like a cell's cytoplasm. Can you imagine how millions of those naked eggs make up each human being?
When you dropped your egg in the vinegar, the chemicals inside the liquid reacted with the shell, breaking it down until it completely dissolved. In this case, the process is called osmosis. If vinegar can do that to an egg, what else do you think it could do? Keep guessing and testing new ways to experiment. With science, projects and results are endless. What happens if you soak the egg in lemon juice? Will you get the same result? What happens if you boil the egg first? There's only one way to find out!