The Cell
The Cell — Unit of Life
Every living organism is built from cells, the smallest units capable of independent life. This chapter introduces the structure of the cell, the roles of its organelles, and how they cooperate to keep the organism alive.
Key idea: A cell is not a bag of chemicals — it is an
organised, compartmentalised system where each structure has a job.
The parts of a cell
The diagram below shows a simplified animal cell. Notice how the nucleus sits centrally, surrounded by the cytoplasm and enclosed by the cell membrane.
How organelles work together
- Nucleus — stores DNA and directs cell activity.
- Mitochondria — release energy through respiration.
- Cell membrane — controls what enters and leaves.
Watch & listen
Deepen your understanding with the linked media below: