cell size

• Organisms are made up of cells.
• Most organisms are multicellular and have cells that are specialised to do a particular job.
• Microscopes are needed to study cells in detail.
• The limits of the light microscope are a barrier to understanding cell structure.
• Animal cells and plant cells have different structures and functions.
• Most animal and plant cells are 0.01 – 0.10 mm in size.
• The smallest thing seen with the naked eye is about 0.05 mm.
• For all cells, a microscope is needed to see them in any detail.
• The best unit to measure most cells is the micrometre, symbol μm.
• For some sub-cellular structures, a smaller unit – the nanometre, symbol nm – is more appropriate.
• In standard form, numbers are written as: A × 10 n A is a number greater than one but less than 10 n is the index or power, always in powers of 10
• The real size of the cell in a book, a micrograph close micrograph A photograph taken of a microscopical image
• The magnification of a cell in micrometres can be calculated using the same formula as in millimetres: Cell measurement = 100 mm 1 mm = 1000 μm 100 mm = 100 x 1000 μm 100 mm = 100 000 μm
• When writing and working with very large or very small numbers, we use standard form.
• One metre can be broken down into the following measurements: Millimetre, mm Micrometre, μm Nanometre, nm \(\frac{1}{1000}\; metre\) \(\frac{1}{1\: 000\: 000}\; metre\) \(\frac{1}{1\: 000\: 000\: 000}\; metre
• The division of a metre can be represented as a fraction: Millimetre, mm \(\frac{1}{1000}\; metre
• A red blood cell's diameter of 7 μm or 0.000007 m could be written as 7 × 10 -6 m in standard form.
• The magnification of a cell in a book, a micrograph close micrograph A photograph taken of a microscopical image
• A population of 120 000 000 microorganisms could be written as 1.2 × 10 8 in standard form.
• The division of a metre can also be represented in standard form: Millimetre, mm 1 × 10 -3 m
• To calculate the magnification of a cell in a book, a micrograph close micrograph A photograph taken of a microscopical image
• The real size of the cell in micrometres is 50 μm.