Cells: Specialised Cells, Tissues And Organs
1.2 Specialised Cells, Tissues And Organs
Cell Specialisation
- Cells adapt their structure to perform specific functions.
- Specialisation increases efficiency in multicellular organisms.
Examples Of Specialised Cells
| Cell | Adaptations | Function |
|---|---|---|
| Red blood cell | No nucleus, haemoglobin, biconcave shape | Transport oxygen |
| Root hair cell | Long extension, thin wall, large surface area | Absorb water and minerals |
| Sperm cell | Tail (flagellum), many mitochondria, acrosome with enzymes | Fertilise egg |
| Ciliated cell | Cilia move in waves | Move mucus and dust in airways |
| Palisade cell | Many chloroplasts, elongated shape | Photosynthesis |
| Nerve cell (neurone) | Long fibre (axon), insulated, branched ends | Transmit electrical impulses |
Written And Compiled By Sir Hunain Zia, World Record Holder With 154 Total A Grades, 7 Distinctions And 11 World Records For Educate A Change O Level And IGCSE Biology Full Scale Course
Levels Of Organisation
| Level | Definition | Example |
|---|---|---|
| Cell | Basic unit of life | Red blood cell |
| Tissue | Group of similar cells with same function | Muscle tissue |
| Organ | Different tissues working together | Heart |
| Organ system | Organs working together | Digestive system |
| Organism | Whole living thing | Human |
Magnification Formula
Magnification = Image size ÷ Actual size
- Actual size = Image size ÷ Magnification
- Image size = Actual size × Magnification
Example
- Image size = 40 mm
- Actual size = 0.04 mm
- Magnification = 40 ÷ 0.04 = ×1000
Written And Compiled By Sir Hunain Zia, World Record Holder With 154 Total A Grades, 7 Distinctions And 11 World Records For Educate A Change O Level And IGCSE Biology Full Scale Course