variation and evolution

• Variation in individuals is due to differences in genes and environment
• Phenotype describes the observable characteristics of an individual resulting from the interaction of genes and environment
• Genes code for proteins and a genome is the combination of all genes in an organism
• Everyone, except identical twins, has a unique genome leading to different combinations of proteins and physical appearances
• Characteristics are determined by the interaction of genes and environment
• Most traits are influenced by multiple genes and environmental factors
• Genetic variation is due to mutations, which are changes in the DNA code
• Most mutations do not affect proteins or the organism's phenotype
• Beneficial mutations can lead to advantages such as disease resistance or improved abilities
• Natural selection is the process where individuals with beneficial mutations are more likely to survive and reproduce
• Charles Darwin observed natural selection and described it as survival of the fittest
• Evolution is the inheritance of certain characteristics over generations leading to changes in a species or the development of new species
• All living species are believed to have evolved from simple life forms over 3 billion years ago
• Darwin's theory of evolution by natural selection has been proven through various examples like antibiotic resistance in bacteria and fossil records
• Evolution occurs through natural selection of genetic changes that result in phenotypes best suited to the environment
• Over time, populations within a species may diverge so much that they can no longer interbreed, leading to the formation of a new species