Transcript here - My Haiku

Genetics Vocab Notes
Mendelian Genetics Video
https://www.youtube.com/watch?v=Mehz7tCxjSE&index=1&list=PLEzC
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• Traits are coded on segments of
DNA called genes
• Alleles: different versions of the
same trait
• How many alleles for each
trait do you have?
• Genotype: the type of alleles an organism has
• Phenotype: the appearance of the organism
• Caused by the genotype
• Mendel found a pattern of
inheritance:
• Dominant: trait always shown
• Recessive: trait “hidden” unless
both alleles are recessive
BB
Bb
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Add a sticky note to our class bar graph if you have:
- Cleft chin
- Hitchhikers’s thumb
- Widow’s peak
- Dimples
- Freckles
- Polydactyly
- Tongue Rolling
- Free earlobes
• Homozygous: have 2 of the same alleles
• Either both dominant or both recessive
• Heterozygous: have 2 different alleles
Tips for Punctiliously Perfect Punnett Squares
• Choose letters to represent your alleles
• Dominant = uppercase letter
• Recessive = lowercase letter
• Pick letters with distinct upper- and lowercases
• Line up mom’s alleles on the side, dad’s on the top
• Heterozygote? Put the capital (dominant) in front
Punnett Square Practice: In Your Notes
A dog breeder wants to know how many puppies he can expect to have
brown coats (a dominant trait) and white coats. He crosses a truebreeding brown female with a true-breeding white male.
What will their puppies look like?
What will the next generation look like?
Punnett Square
Whiteboard Practice
A green pea plant (Gg) is crossed
with a yellow pea plant (gg).
What percentage of their offspring will be yellow?
A green pea plant (Gg) is crossed
with a yellow pea plant (gg).
What percentage of their offspring will be yellow?
Mrs. Weasley has freckles, while Mr. Weasley
does not. Mr. and Mrs. Weasley each have a
homozygous genotype. All of their children
have freckles.
Write the genotypes for Mr. and Mrs. Weasley
What are the genotypes of the Weasley
children?
Are they homozygous or heterozygous for
freckles?
Ron Weasley marries Hermione Granger
(against J.K. Rowling’s better judgement,
per recent news).
Hermione does not have freckles.
What is the probability that their children will not
have freckles?
Skill Check! Answer on an index card
In purple people eaters, one-horn is dominant and no
horns is recessive.
Draw a Punnet Square showing the cross of a
heterozygous purple people eater with a purple people
eater that does not have horns.
What are the genotypes and phenotypes of their
potential offspring?