Download Why do you look the way you do?

What is a chromosomal disorder?
• What does trisomy mean?
• What is nondisjunction and when can it
occur?
• What is Kleinfelters? Turners? What sperm
and eggs have to combine for these
disorders to occur?
WHY DO YOU LOOK THE WAY YOU DO???
We are going to take a survey for
some specific traits…
• Please mark whether which characteristic
you have
Do you have a chin with a cleft? Or a chin
without a cleft?
This is a chin with a
Cleft.
Do you have a widows peak?
• Widows peak
How about an 80’s cut and crazy swoop bangs…..
Just kidding.
Do you have mid-digit hair?
• That’s right, hair on your hand between the
two digits.
I do!
Do you have attached ear lobes?
Unattached
Attached
Do you have a hitchhikers
thumb?
hitchhikers
Nonhitchhiker
Can you roll your tongue?
Are you ready to smell something
gross?
• Is your second toe longer than your big toe?
What kind of weirdo
takes a picture of their
toes and puts it on the
inter-net?
• Do you have Dimples like Miss
Hollingworth? Divits in your cheeks?
• When you cross your arms which do you
put on top?
Our Traits
Presence of Traits in Miss H’s Class
Trait
Cleft
Widows Peak
Yes No
Do You see any patterns?
• What is the relationship between
percentages of various traits?
• Are the traits distributed equally in our
class?
Why do you look the way you do?
• You appearance is determined by the genes you
have inherited from your mother and father.
• There are different types of these genes which are
called alleles.
• For example there are different alleles for Ear
shape
– Ex attached, unattached
• The physical appearance of each trait is called the
phenotype.
More on alleles..
• The specific alleles of a specific trait are the
genotype
– The dominant allele is written as a capital letter
– The recessive allele is written as a lower case letter
• If an allele is Dominant it will “cover up the other
allele
• Thus if the genotype is TT or Tt the dominant
trait will show. If tt is the geotype the recessive
trait is shown.
Your job is to determine if a
specific trait is recessive or
dominant
• Recessive traits show up 25% of the
population
• Dominant traits show up in 75% of t he
population
You job is to design an experiment
to determine if a trait is recessive
or dominant.
• Choices of traits
–
–
–
–
–
Freckles or No Freckles
Broad Lips or thin lips
Left or right handed
Crossing Legs (Left over right or Right over left)
Bent pinkies or straight pinkies
You will create your own
• Purpose
• Procedure (Must be approved before you
run your experiment
– Materials and Steps
Data
• Data Analysis
• Conclusion