lesson
Cells work together at larger scales
1 · Learn
In multicellular organisms, specialised cells form tissues, tissues form organs and organs work in systems. Muscle tissue contains cells that contract; the stomach contains several tissues working together in digestion.
An organ is not simply one very large cell. Different tissues contribute different jobs, such as contracting, lining a surface or transporting substances. A unicellular organism carries out life processes within one cell rather than having these multicellular levels.
2 · Worked example
I trace muscle cell to muscle tissue to stomach to digestive system to person. This shows levels of organisation without claiming the stomach contains only muscle.
3 · Your turn
Why is the stomach not described as one tissue?
Check your answer
It contains several tissue types with different functions that work together as an organ.
4 · Apply your learning
Build a second hierarchy for a plant using verified examples, and explain where your example's cells are specialised.
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Check a calculation · Year 5 onward
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Powers, roots and trigonometry · Year 7 onward
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