Biology- The Basics - Writers Writing - http://maxpages.com/fanficsnstuff/Overview

Biological Science: The Study of Life

A. The Scientific Method: how scientists study biology.
1. Observe phenomena and formulate testable and falsifiable hypotheses.
2. Test hypothesis, collect data, and analyze statistically (if nessecary).

B. What is life?
1. Characteristics: metabolism, reproduction, growth, movement, responsiveness, complex organization.

Evolution

The concept that all organisms are related to each other by common ancestry is the unifying theme in biology.

A. Natural Selection- a mechanism for how evolution occurs.
1. Survival of those offspring best adapted to the conditions in which they live.
a. Individuals produce sexually many more offspring than could possibly survive.
b. These offspring are not identical (in most situations), but show variations based on genetic differences.
c. Essentially, those individuals with variations that allow them to survive (i.e., adaptations) to the age of reproduction can pass their genes on to the next generation.
d. Thus, nature is selecting offspring and shaping the evolution of species.
e. Charles Darwin and Alfred Wallace, 19th century biologists, formulated the concept of natural selection.

B. Artificial Selection- human selects traits in offspring (ex, domesticated animals, farm crops.)

(Source: BarCharts, Inc: Biology: The Basic Principles of Biology.)
Check out BarCharts on the web!
Dictionary Definition:

Natural Selection: (n) The natural process that results in the survival of individuals or groups best adjusted to their environment. (The Merriam-Webster Dictionary: The Words You Need Today)

Natural Selection is a process that allows Evolution of a species to occur. It occurs when some individuals of a population are better able to adapt to their environment, and are therefore able to produce more offspring. In this way, Nature selects which members of a population are fit to survive long enough to produce offspring. As a result, those who produce more offspring have more influence on the gene frequencies of the next generation. As the member produces more offspring and the offspring pass on their genes to the next generation, eventually the entire species is affected and genetically made easier to adapt to the environment, therefore allowing the process of evolution to occur.

The Phyletic Gradualism model shows the theoretic evolution of a species in which they change slowly at a more or less constant rate through time into other species.

Opposite to the Phyletic Gradualism theoretic model of Evolution is the Punctuated Equilibrium theoretic model of evolution. While the Phyletic model theorizes that a species changes at a constant rate through time, the Punctuated model theorizes that species stay unchanged for a long time, and then rapidly change due to major alterations of the environment.

Dictionary Definition:

Species: (n, pl) 1. sort, kind. 2. a category of biological classification ranking just below the genus or subgenus and comprising closely related organisms potentially able to breed with one another. (The Merriam-Webster Dictionary: The Words You Need Today)

A species is the largest natural population of organisms that can interbreed to produce fertile offspring. Members of one species are reproductively isolated from members of all other species (i.e., they cannot mate with them to produce fertile offspring).

(Note: This is only an overview, Im not a scientist, I dont have all the facts, and please dont sue me! Im only 15 dammit!)

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Page Updated Sat Aug 18, 2001 11:09pm EDT