The Size of Things Viruses are so small that scientists use electron microscopes to see them. 1. Study the number line to help you understand the size differences between viruses, cells, and larger organisms. 2. Then choose common objects to represent two organisms, and write two size-comparison analogies.
1 nanometer 1micron 1 milimeter 1 centimeter 1meter 1 kilometer (10-9m) (10-8m) (10-7m) (10-6m) (10-5m) (10-4m) (10-3m) (10-2m) (10-1m) (100m) (101m) (102m) (103m)
Simple Viruses Typical Typical Some Typical Humans Blue Tallest carbon- bacteria animal unicellular mice whales trees containing & organisms, molecules plant such as cells dinoflagellates
Analogy: 1.0 Item #1 from Approximate Common object Item #2 from Approximate Size difference Common object number line size representing number line size between items representing item #1 1 and 2 item # 2 Paper clip Room height -7 10-5 2 1. Virus 10 (about 3 cm) Cell 10 or 100 (about 300 cm)
2.
3.
Write your analogy in sentence form. A virus is to a paper clip as a cell is to the height of a room. 1.
2.
3.
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