Santiago Callejas

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Human Traits The Physical Aspect

• Santiago Callejas
• Cherish Centeno
• Romina Chanduvi
• Aileen Perez

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Abstract
Since, dominant traits have supremacy over
recessive traits, we have created and conducted
surveys that establishes whether dominant traits
are more common than recessive traits in the
Miami-Dade College Wolfson Campus student
population.
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Hypothesis
If dominant traits prevail over recessive traits,
then dominant traits should be more commonly
found in Miami Dades College student population.
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Observation/ResearchOverview

• Researched
• What are human traits?
• Where do they come from?
• Mendelian Genetics
• Dominant VS Recessive
• Sex linked traits
• Shuffling the deck
• Types of inherited human traits

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What Are Human Physical Traits?
The genetically determined characteristic or
condition of an individual. These
characteristics are controlled by one or more
genes.
Most genes have two or more variations, called
alleles. For instance, the gene for hairline
shape has two alleles widows peak or straight.
An individual may inherit two identical or two
different alleles.
The eye color gene, also has more than one
variation.
Straight Hairline Widows Peak

Hairline
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Where Do They Come From?

• Physical traits that are observable
  characteristics determined by specific segments
  of DNA called genes. Multiple genes are grouped
  together to form chromosomes, which reside in the
  nucleus of the cell.

• Every cell (except eggs and sperm) in an
  individual's
• body contains two copies of each gene.
  This is due
• to the fact that both mother and father
  contribute a
• copy at the time of conception.

• This original genetic material is copied each
  time a cell divides so that all cells contain
• the same DNA. Genes store the information needed
  for the cell to assemble
• proteins, which eventually yield specific
  physical traits.

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Mendelian Genetics
Mendel studied traits how they are passed on to
offspring

• He established 2 possible "alleles" for each
  trait. The combination was (1 from mom, 1 from
  dad) which is called your "genotype"
• There are more than 2 alleles for some traits.
  Most traits, in fact, are affected by more than 1
  gene

Gregor Mendel (1822-1884)
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Dominant VS Recessive
Recessive Gene is expressed only when two copies
of the gene are present 2 Matching Allele -In
homozygous individuals, The allele that is
expressed is either the recessive allele or the
dominant allele.
Dominant Gene is expressed in a person who has
only one copy of that gene 2 Different
Allele -In heterozygous individuals, the allele
that is expressed is the dominant allele.
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Sex-Linked TraitsGregor Mendel

• In the case of genes located on the X chromosome,
  females would have the usual 2 alleles for each
  gene but males only have 1 X chromosome and thus
  1 allele (the Y chromosome contains only a small
  number of genes related to gender)

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Shuffling the Deck(Gregor Mendel)

• Chromosomes of offspring dont have a half thats
  clearly from dad and a half that's from mom.
  During duplication there is "crossing over" of
  bits of each half.

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Types of Traits
Trait Dominant Recessive
Hairline Widows peak hairline Straight hairline
Dimples Dimples No dimples
Earlobes Detached Earlobe Attached Earlobe
Freckles Freckles No freckles
Tongue Roller No roller
Thumb Straight thumb hitch-hikers thumb
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Who was surveyed?
Miami- Dade Wolfson Campus
Determining Factors Race, gender and writing hand

• Recessive Traits
• -Straight hairline
• -No dimples
• -Attached Earlobe
• -No roller
• -hitch-hikers thumb

Dominant Traits -Windows peak
hairline -Dimples -Free ear lobe -Roller
-Straight thumb
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Results
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Earlobe Trait
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Dimples
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Hairline Trait
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Thumb Trait
Hitch-Hikers
Straight
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Tongue Trait
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Conclusion
Results show that our hypothesis was indeed
correct. They are more people within the
population who express dominant traits rather
than recessive traits. However, our studies also
revealed that there are many among the population
that display recessive traits.
Dominant Recessive
Straight Hairline Attached earlobe
Straight Thumb No Dimples
Tongue roller
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Quiz!!!

• 1. Name a leading recessive trait found in the
  Miami-Dade student population.
• Freckles
• Dimples
• Tongue roller
• Attached earlobe
• 2. Is tongue rolling a dominant or recessive
  trait?
• 3. Who is going to get an A for the presentation
• Human traits group
• Human traits group
• Human traits group
• Human trait group

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THANK YOU