Ess Miller Chapter Notes Chapter 4

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Cornell Notes for Miller Chapter 4
Biodiversity
* The biodiversity found in genes, species, ecosystems, an ecosystem processes is vital to sustaining life on earth. * Part of the Earth’s natural capital
* Biodiversity is the variety of the earth’s species, the genes they contain, the ecosystems in which they live, and the ecosystem processes such as energy flow and nutrient cycling that sustain all life. * Renewable resource

* Plays a role in preserving the quality of the air and water and maintaining the fertility of soils. Genetic diversity
* The variety of genetic material within a species or a population * Enables life on earth to adapt to and survive dramatic environmental changes. Species diversity
* The number and abundance of species present in different communities Ecosystem
Diversity
* The variety of terrestrial and aquatic ecosystems found in an area or on the earth (deserts, grasslands, forests, etc.). * Each ecosystem is a storehouse of genetic and species diversity. Functional

Diversity
* The biological and chemical processes such as energy flow and matter recycling needed for the survival of species, communities, and ecosystems. Biological
Evolution
By natural
Selection
* The scientific theory of evolution explains how life on earth changes over time through changes in the genes of population. * Populations evolve when genes mutate and give some individuals genetic traits that enhance their abilities to survive and to produce offspring with these traits (natural selection). * Biological evolution-the process whereby earth’s life changes over time through changes in the genes of populations. * The idea of evolution came from early Greek philosophers, but Charles Darwin came up with an explanation of evolution. * Russell Wallace proposed the concept of natural selection, but once again Darwin explained natural selection. * Darwin and Wallace observed that-

* There is a constant struggle between organisms to gain enough food and resources to survive and reproduce. * Individuals that have a specific advancement are more likely to survive, reproduce, and have offspring with similar survival skills. * This was due to a trait the individuals had but the rest of the organisms did not have. * Darwin and Wallace concluded that these traits would become more prevalent in future generations through natural selection. * Natural selection-occurs when some individuals of a population have genetically based traits that enhance their ability to survive and produce offspring with the same traits. A change in the genetic characteristics of a population from one generation to another is known as biological evolution. * According to the theory of evolution through natural selection, life has evolved into six major groups of species, or kingdoms. * Explains how life has change in the past 3.7 billion years and why life is so diverse today. * Most of the earth’s life history we have learned through fossils. Scientists also examine the kinds of life found at different layers of glaciers or mountain tops. * The fossil record is uneven and incomplete because some forms of life don’t leave fossils and some fossils decompose. The fossils we do have represent about 1% of all life forms that have ever lived. Mutations

* Evolution through natural selection involves changes in a population’s genetic makeup through successive generations. Populations, not individuals, evolve by becoming genetically different. * The first step to change a population genetic makeup is genetic variability in a population. * Genetic variety occurs through mutations (random changes in the structure or number of DNA molecules in a cell that can be inherited by offspring). * The random changes usually occur when the DNA molecules are copied during reproduction. * Some mutations can also occur due to radioactivity, X rays, and...
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