[BIOLOGY 1B] - Final Exam Guide - Comprehensive Notes for the exam (56 pages long!)
Document Summary
Charles darwin said natural selection is used as mechanism by which species adapt to environment and by which new species ultimately arise from ancestral species. Phenotypes, apparent characteristics, depend on its genotype, or an individual"s dna. Particular set of alleles (variants of a gene) at given location (locus) within dna. Two identical alleles are homozygous (eg. aa) Heterozygous carry two different alleles and the character is expressed by dominance of the alleles (eg. aa) Researchers discovered deoxyribonucleic acid (dna) that contains long sequences of four nucleotides: adenine, thymine, cytosine, and guanine. Gene is a section of dna strand that determines sequence of amino acids in the protein for which it codes. New traits arise from mutations, which are changes in the nucleotide sequence of a gene. New mutations start at low frequency, but can become 100% frequency in pop if individuals survive and reproduce more than the individuals that lack it (fixation)
