Cells Under the Microscope
Understand that all living organisms are made of cells and use a light microscope to observe, interpret, and record cell structure
What a learner can do afterwards
- States that all living things are made of cells
- Prepares or examines a slide of cells (e.g. onion skin, cheek cells) under a microscope
- Draws and labels a diagram of cells observed
- Identifies nucleus, cytoplasm, and cell membrane in a microscope image
1 · Read
Every living thing you have ever seen, a tree, a dog, or you, is built from cells. A cell is the smallest unit that is still alive.
Most cells are far too small to see with your eyes alone, so scientists use a microscope to make them big enough to study.
To see cells, you peel a thin, see-through layer from the inside of an onion, or gently scrape the inside of your cheek. You place that layer on a glass slide, add a drop of stain to make the parts easier to see, then lower a thin glass square called a coverslip on top.
Zara places onion skin on a slide and looks through the microscope. She sees rows of clear, brick-shaped boxes. Inside each box she spots a small dark circle. That dark circle is the nucleus, the part that controls the cell. She draws what she sees and labels each part.
The cell membrane is the thin edge around each cell. It holds the cell together and controls what moves in and out.
The cytoplasm is the jelly-like fill inside the cell. The nucleus is the dark round spot that controls the cell.
All living things are built from cells, and a microscope lets you see each one's membrane, cytoplasm, and nucleus.
Five rewritten readings were written for this dataset. Per-item provenance in file.
2 · Watch
Take it off screen
Where it sits
Learn first
Nothing; this is a starting point.
Where this leads
Jobs that lean on this skill. Follow one to see everything it is built on.
8 questions wait behind this lesson, each with its answer explained. Every answer feeds the sky: stars light as they are learned, and dim when it is time to come back.