Download H H

FRIDAY, Nov. 4th
You are homozygous dominant for a hairy
chest and your sweetie’s heterozygous.
Hairy (H) is dominant to not hairy (h).
• Draw a punnett square to determine the
amount of chest hair your offspring may
have!
• Tell the possible genotypes and phenotypes
of your babies!!!
You are homozygous dominant for a hairy chest and your
sweetie’s heterozygous.
Hairy (H) is dominant to not
hairy (h).
H
H
H
HH
HH
h
Hh
Hh
• HH x Hh
•
•
punnet square
Tell the possible genotypes and phenotypes of your
babies!!!
• Genotypes: 50% HH; 50% Hh (1:1)
• Phenotypes: 100% hairy-chested, 0% not
hairy
Longer 2nd toe is
dominant over 2nd toe
shorter than big toe.
Tongue-Rolling: Rolling up
edges (dominant trait) vs
not rolling (recessive
Pinky:
Straight pinky
(recessive trait) vs.
Bent pinky (dominant
trait)
Mid-digit hair:
Mid-digit hair
(dominant trait)
vs.
No mid-digit hair
(recessive trait)
Dimples:
Dimples (dominant trait)
vs.
No dimples (recessive
trait)
Thumbs:
Straight thumb
(dominant trait) vs.
Curved thumb
(recessive trait)
Earlobes: Free ear
lobes (dominant
trait) vs. Attached
ear lobes (recessive
trait)
Forelock: White forelock
(dominant trait) vs. No white
forelock (recessive trait)
A white forelock is a patch
of white hair, usually located
at the hairline.
Widow's Peak (left) is
dominant over no widow's
peak hairline.
6.6 KEY CONCEPT
Independent assortment and crossing over
during meiosis result in genetic diversity!!
Genetic diversity!! How the heck
does it happen?
Random, increases unique combos
of genes! 64 trillion combos in
humans!!!
Indep. asstmt. of chromos increases
unique gene combos…8 million diff.
combos of chromos in gametes!!!
Exchange of chromo segments between
hom. chromos during prophase I, new
combos of genes, from mom and dad!
So, what’s this crossing over thing?
• exchange of chromo. segments
between homologous chromos!
• during prophase I (meiosis I)
• results in new combinations
of genes
Pair up!!!
Segments
cross!!
Remember,
chromosomes contain
MANY genes!!
– Genes located near each other on same chromo
usually inherited together!!!
– farther apart  usually separated by crossing over
– Researchers use this to calculate distances on
chromosomes…(but you don’t need to know how!)

PHUN Punnett Practice 
Let’s check your answers…
Then the Quiz!!