Variation
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1. The document discusses sources of variation in organisms, including both genetic factors like gene mutations and chromosomal mutations, as well as environmental factors like nutrition, temperature, and light intensity. 2. Variation can be continuous, with a range of values, or discontinuous, where an organism either has a characteristic or does not. Gene mutations like sickle-cell anemia or chromosomal mutations like Down's syndrome can cause variation. 3. An example is given of industrial pollution selecting for dark-colored moths that blended in better with the soot-covered trees, making light-colored moths more vulnerable to predation until environmental regulations reduced pollution.
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2. Fossils like Archaeopteryx provide direct evidence as a connecting link between reptiles and birds. A series of horse fossils show evolution of the species over time.
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3) Extinction patterns include background extinction and mass extinctions caused by events like asteroids or climate change.
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uttamrajtimilsina@gmail.com
*All Right Reserved**
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- 1. LEARNING OBJECTIVES: 1. Understanding variation in organisms 2. Understanding the causes of variation 3. Being respectful towards one another despite variation VARIATION The difference between organisms of the same species.
- 2. Continouos variation is the variation that have range of values from the smallest o the biggest . Eg. shortest – tallest lightest - heaviest Discontinuous variation – which have no range: you either have the characteristic ,or you do not OR you can do something or you cannot.
- 3. Examples of continuous variation Exapmles of discontinuous variation
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