Every living thing, from the tiniest bacterium to a towering tree, is built from cells. Explore what's inside one, and how plant and animal cells differ.
The cell is the smallest structural and functional unit of every living organism. Robert Hooke first observed and named cells in 1665, looking at cork under a microscope.
Who first observed and named cells, and in what year?
Robert Hooke, in 1665, while observing cork under a microscope
Plant cells have a rigid cell wall, chloroplasts for photosynthesis, and a large central vacuole. Animal cells lack all three of these structures.
Name one structure found in plant cells but not in animal cells.
The cell wall (chloroplasts and a large central vacuole are also correct answers)
Osmosis is the movement of water across a semi-permeable membrane, from a region of higher water concentration (a dilute solution) to a region of lower water concentration (a concentrated solution).
If a cell is placed in a very salty (concentrated) solution, does water tend to move into or out of the cell?
Out of the cell — water moves from the less concentrated solution inside the cell toward the more concentrated salty solution outside
1. Who discovered and named the cell, and when?
2. Name one structure present in a plant cell but absent in an animal cell.
3. What is osmosis?
4. Why do chloroplasts matter to a plant cell?
5. Why is the cell called the basic unit of life?