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Genetics. How does my DNA make me, well, ME?. What is an allele ?. Definition: Different or alternative forms of the same gene Ex. alleles for height It’s the combination of these alleles that determines what we are. How can I have a combination of alleles?.
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Genetics How does my DNA make me, well, ME?
What is an allele? • Definition: Different or alternative forms of the same gene Ex. alleles for height • It’s the combination of these alleles that determines what we are.
How can I have a combination of alleles? • Remember in Meiosis: 23 chromosomes from mom & dad each • Two matching chromatids from each parent; two matching genes from each parent. • This means that we receive one allele from mom & one from dad
Why do I only have one parent’s nose or eyes then? • The “winning” or dominating allele is always referred to as the dominant • The suppressed or hidden allele is always referred to as the recessive One allele dominates over the other and is expressed.
Alleles are often represented by a single letter: Homozygous (AA or aa) refers to two alleles that are the same Heterozygous (Aa) refers to two alleles that are the different
Important Terms before we move on: Genotype is the allele combination of a trait (ex. Aa, AA, or aa) Phenotype is the physical expression of that trait (ex. hair color, blood type, etc)
Let’s Start Our Next Activity! • The next activity is related to heredity and allows us to practice the new terms we learned in a fun way. • Heredity = the passing of characteristics from parents to offspring