Transcript Inherited-Human-Trait-Powerpointx

Heredity and Reproduction
Inherited Human Traits
Trait
A trait is inherited from from genes that are
found on DNA.
Attached Earlobes vs. Detached Earlobes
Unattached earlobes is
considered a dominant
gene
Attached earlobe is
considered recessive
Tongue Rolling
Famous geneticist Alfred Sturtevant noted
about 70% of people of European ancestry
are able to roll their tongues.
30% of twins do not share this trait.
Ability to roll tongue
is dominant gene.
Recessive if you cannot
roll tongue
Cleft Chin and Dimples
Cleft chin present dominant
No cleft chin recessive
Dimples present dominant
Lack of dimples recessive
Handedness: Righty or Lefty???
Left handed is recessive Right handed is dominant
Straight or Curly
Straight hair is recessive
Curly hair is dominant
Hairline Shape
Widows peak is dominant
Straight line is recessive
Hand Clasping: Might have some genetic
component to it
Cross left thumb over right 55%
of the people do this
Cross right thumb over left
45% of people do this
Freckles
Freckles present dominant
Absence of freckles recessive
PTC Testing: Bitter taste receptor
• 75% people can taste PTC
• PTC like chemicals found in vegetables
like cabbage, brussel sprouts, and
broccoli
• PTC taster is dominant
Let’s see if you can taste it!
http://learn.genetics.utah.edu/content/inheritance/ptc/