The document summarizes key concepts about genetics and inheritance including:
1) Chromosomes condense during cell division and offspring inherit chromosomes from parents, containing DNA from the mother and father.
2) In humans there are 46 chromosomes in each cell organized into 23 chromosome pairs.
3) Genes can have more than two alleles that are codominant or recessive and determine blood type or other traits.
4) Mutations in sperm, egg or offspring can cause genetic disorders but some mutations may be beneficial for survival in the environment.
Multiple Alleles, Sickle Cell Evolution, Pedigrees, & Sex Linkage
1. As a cell prepares to divide the DNA becomes condensed into compact structures called chromosomes (chromo = colored, somes = bodies) Offspring get DNA from parents by inheriting chromosomes!!!
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3. In humans, each body cell has 46 chromosomes in 2 sets (23 pairs) One set of chromosomes come from the mother and one set comes from the father
4. There can be more than two alleles for a gene! Human Blood Type has three alleles: A, B, and i AB are codominant, while i is recessive to both A and B Genotype Phenotype AA A Ai A BB B Bi B ii O AB AB More Complexity
6. If a mutation occurs in a sperm or egg, it may be transmitted to offspring If that mutation has a negative effect on the phenotype of an organism, the mutant condition is referred to as a genetic disorder (hereditary disease) BUT, not all mutations are harmful!!! Some mutations may make an individual better adapted to its environment, improving its chances for survival