Genetics Final Cheat Sheet

Genetics Final Cheat Sheet - Mendels Laws 1 Principle of...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
Mendel’s Laws 1. Principle of Segregation: Each individual diploid organism possesses two alleles for any particular characteristic. These two alleles segregate (separate) when gametes are formed, and one allele goes into each gamete. Furthermore, the two alleles segregate into gametes in equal proportions. 2. Concept of Dominance: When two different alleles are present in a genotype, only the trait encoded by one of them—the dominant allele—is observed in the phenotype. 3. Principle of Independent Assortment: Alleles at different loci separate independently of one another. Laws of Probability 1.Probability of two or more independent events calculated by multiplying probability of each 2. Probability of two mutually exclusive events calculated by adding together Ex. AaBbccDdEe x AaBbCcddEe What is probability of aabbccddee? Aa x Aa yielding aa (1/4) Bb x Bb yielding bb (1/4) cc x Cc yielding cc (1/2) etc. X 2 test X 2 = - observed expected2expec ted Calculate expected by finding the proportions and multiplying by total Degrees of freedom = classes – 1 Special Cases 1. Incomplete Dominance: When the heterozygote is an intermediate between parents (ex. Red and white plant produce pink) 2. Codominance: When heterozygotes exhibit both phenotypes (ex. Blood type) 3. Lethal allele: when homozygous recessive/dominant kills organism; results in 2:1 ratio 4. Multiple alleles: number of genotypes possible will be [n(n+1)]/2 where n equals number of alleles 5. Novel Phenotypes: A_B_, aaB_, A_bb, and aabb all produce different phenotypes in 9:3:3:1 ratio 6. Recessive Epistasis: recessive of one masks the
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 05/04/2009 for the course BICD 660930 taught by Professor Reinagel during the Spring '09 term at UCSD.

Page1 / 4

Genetics Final Cheat Sheet - Mendels Laws 1 Principle of...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online