JOURNAL QUESTION
14 Jan 2013
 Which form of reproduction is most likely to
give a population of organisms genetic variety?

 Why?
Vocabulary
 Allele Segregation Activity

JOURNAL QUESTION

16 Jan 2013

How is an allele related to a gene? Explain and
give an example.
TODAY’S APPS
Nearpod Student
 Funny2018


Student PIN: FGOJO

Set up Google Drive Science Folder
 5-Lastname,FirstName
JOURNAL QUESTION
Male alleles are both brown.
 Female alleles are brown and white.
 Show the possible outcomes for the offspring.

GENOTYPE VS. PHENOTYPE
LEARNING TARGET
I
can differentiate and make
connections between phenotypes
and genotypes of organisms.
GENE

The instructions for a specific inherited trait
that are found on one section of a chromosome
of DNA.
 For
example, you have a gene(s) for each of the
following traits:
 Hair
color
 Eye color
 Hitchhiker’s thumb
 Tongue rolling
 Hairline
 Earlobes
ALLELE
The different forms of a gene.
 Each gene is made up of at least two alleles,
one inherited from the male parent and one
from the female parent.

 For
example:
 Gene
for hair color: Blonde hair OR Black hair
 Gene for eye color: Blue eyes OR Brown eyes
 Gene for thumb shape: Hitchhiker’s thumb OR Straight
thumb
 Gene for tongue rolling ability: Can roll tongue OR Can’t
roll tongue
 Gene for hairline: Widow’s Peak OR Straight hairline
PUNNETT SQUARES
HOW CAN IT BE DETERMINED WHICH
ALLELES AN OFFSPRING WILL
INHERIT?
DOMINANT ALLELES



Alleles that cover up, hide, mask, or over-power other
alleles.
The trait associated with the dominant allele always
shows up when it is present (it dominates!).
Writing convention:


UPPERCASE letters.
For example:


H = Dominant (Straight thumb)
h = Recessive (Hitchhiker’s thumb)
Hh = Straight thumb
 HH = Straight thumb
 hh = Hitchhiker’s thumb

RECESSIVE ALLELES



Alleles that are covered up or hidden.
The recessive trait will only show up if a dominant
allele is NOT present.
Writing convention:


lowercase letters
For example:




W = Dominant (Widow’s peak)
w = Recessive (Straight hairline)
Ww = Widow’s peak
ww = Straight hairline
HOMOZYGOUS
Both alleles are the SAME as each other.
 Homo = same

 For
example:
 TT
= homozygous DOMINANT
(both alleles are dominant)
 tt
= homozygous RECESSVIE
(both alleles are recessive)
HETEROZYGOUS
Each allele is DIFFERENT from each other.
 Hetero = different

 For
example:
 Hh
 Ss
 Ww
 Tt
GENOTYPE
The genes that an organism has in their DNA
 Genotype = Genes
 Represented by letters

 Examples:
 Hh
 BB
 tt
 Dd
PHENOTYPE

The traits or characteristics of an organism
 (What
it looks like)
Phenotype = “Features”
 Examples:

 Brown
or blonde hair color
 Brown or blue eye color
 Hitchhiker’s or straight thumb
 Tongue rolling ability or not
 Widow’s peak or straight hairline
PUNNETT SQUARE
Female
Alleles
Male
Alleles
EYE COLOR
BROWN IS DOMINANT TO BLUE
.
Use the letter “B”
B = BROWN allele (dominant)
b = blue allele (recessive)
RIHANNA
Brown is dominant to blue.
Rihanna has brown eyes.
What is her PHENOTYPE?
What is her GENOTYPE?
RIHANNA
Brown is dominant to blue.
PHENOTYPE: brown eyes
GENOTYPE: BB or Bb
BRAD PITT
Brown is dominant to blue.
Brad has blue eyes.
What is his PHENOTYPE?
What is his GENOTYPE?
BRAD PITT
Brown is dominant to blue.
PHENOTYPE: blue eyes
GENOTYPE: bb
HAIRLINE
HAVING A WIDOW’S PEAK IS DOMINANT TO
HAVING A STRAIGHT HAIRLINE
Use the letter “W”
W = WIDOW’S PEAK allele (dominant)
w = straight hairline allele (recessive)
Widow’s peak is dominant to normal hairline.
JOHN TRAVOLTA
John has a widow’s peak.
What is his PHENOTYPE?
What is his GENOTYPE?
Widow’s peak is dominant to normal hairline.
JOHN TRAVOLTA
PHENOTYPE: widow’s peak
GENOTYPE: WW or Ww
LEBRON JAMES
Widow’s peak is dominant to normal hairline.
LeBron has a normal hairline.
What is his PHENOTYPE?
What is his GENOTYPE?
LEBRON JAMES
Widow’s peak is dominant to normal hairline.
PHENOTYPE: normal hairline
GENOTYPE: ww
DO YOU HAVE A WIDOW’S PEAK?

If yes, what is your genotype?

If no, what is your genotype?

Which geneotype has could possibly be
heterozygous? Why?
SKIN
FRECKLES ARE DOMINANT TO NO FRECKLES
(use the letter “F”)
JENNIFER LOPEZ
Freckles are dominant to no freckles.
JLo has no freckles.
What is her PHENOTYPE?
What is her GENOTYPE?
JENNIFER LOPEZ
Freckles are dominant to no freckles.
PHENOTYPE: no freckles
GENOTYPE: ff
LINDSAY LOHAN
Lindsay has freckles.
What is her PHENOTYPE?
What is her GENOTYPE?
Freckles are dominant to no freckles.
LINDSAY LOHAN
PHENOTYPE: freckles
GENOTYPE: FF or Ff
Freckles are dominant to no freckles.
LADY GAGA
Freckles are dominant to no freckles.
Lady Gaga has
no freckles.
What is her PHENOTYPE?
What is her GENOTYPE?
LADY GAGA
Freckles are dominant to no freckles.
Lady Gaga has
no freckles.
PHENOTYPE: no freckles
GENOTYPE: ff
DIGITS (FINGERS AND TOES)
POLYDACTYLY IS DOMINANT TO 5 DIGITS
(use the letter “D”)
“NORMAL” 5 DIGITS
Polydactyly is dominant to 5 digits.
These people have 5 digits.
What is the PHENOTYPE?
What is the GENOTYPE?
“NORMAL” 5 DIGITS
Polydactyly is dominant to 5 digits.
PHENOTYPE: 5 digits
GENOTYPE: dd
Polydactyly is dominant to 5 digits
POLYDACTYLY (EXTRA DIGITS)
These people have Polydactyly.
What is the PHENOTYPE?
What is the GENOTYPE?
Polydactyly is dominant to 5 digits
POLYDACTYLY (EXTRA DIGITS)
PHENOTYPE: Polydactyly
GENOTYPE: Dd or DD
ALBINISM


Lack of pigmentation
Recessive trait

Use the letter “P”


What is the genotype of
this family?
What is the phenotype?