Cells are the basic units of living things. Some organisms have one cell; others have many specialised cells. In a typical plant or animal cell, the membrane regulates entry and exit, cytoplasm is where many reactions occur, and the nucleus contains most genetic material and helps regulate activities.
Mitochondria support aerobic respiration and transfers into usable forms of energy. Ribosomes build proteins. Match each structure to its own role rather than treating cell parts as interchangeable. Typical diagrams are simplified and enlarged. Not every living cell has every structure shown: bacteria are living cells without a nucleus.
Example 1
Which cell structure regulates entry and exit of substances?
The cell membrane. It forms a selective boundary around the cell.
Example 2
A cell is actively building many proteins. Which structure directly assembles them?
Ribosomes assemble proteins; the nucleus stores genetic information, while mitochondria support energy transfers.
Watch out:Typical plant and animal cells have nuclei, but bacteria lack a nucleus.
Cell structures and functions practice | Year 8 Science | Ascent Arcade