ACT Preparation / Unit 22 ACT 2101 short lesson, about 20 seconds
The Cell
Captions available
The idea
The cell is the smallest unit of a living thing. All cells share a plasma membrane, cytoplasm, DNA as their genetic material, and ribosomes; eukaryotic cells also have a nucleus and other organelles.
In practice
Mitochondria make ATP, the cell's main energy-carrying molecule; chloroplasts in plant cells carry out photosynthesis.
Where people slip
Prokaryotes, such as bacteria, lack a nucleus and other membrane-bound organelles.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
Builds on
- Nothing. This is a starting point.
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