3chapter11
DESCRIPTION
TRANSCRIPT
CHAPTER CHAPTER 1111
Introduction to Genetics
Gregor Mendel
• Austrian monk who worked with true-breeding pea plants
• He cross-pollinated them
Angela + Allie
Basics of What Mendel Learned
• Genes passed from parents to offspring
• Dominant allele that will show up• Recessive allele that will not show
up• Alleles separate independently
Allie Presher
Phenotypes vs. Genotypes
Examples of phenotypes:1. Tall pea plants2. Brown hair in humans
Examples of genotypes:1. TT homozygous
Tt heterozygoustt homozygous
2. BB
Bb
bb
Allie Presher
Punnett Squares
Punnett squares show the probability of possible outcomes of certain traits in organisms.
Angela Nguyen
Incomplete Dominance and Codominance
Angela Nguyen
Example of Incomplete Dominance:
Example of Codominance:
Polygenic Traits
• Controlled by two or more genes– Example:
Skin color in humans
Angela Nguyen
Meiosis
Allie + Angela
Linked Genes
• Genes that are on the same chromosome: they stay together– Example:
Black body and reduced bristles on fruit flies
Allie Presher