Download Intro Genetics Grade Graph and Allele Graph






Place the date of each assignment on the x-axis
near the bottom of your paper leaving some extra
room
Place percentage marks starting from 0 to 100% on
the y-axis
Add a negative value to your y-axis—missing
assignments—below the 0 on the y-axis
Create a colored histogram (bar graph) showing
how much credit (percentage) you received per
assignment
Missing assignments should show a bar going
below the x-axis

What is a Gene?


Recall from your cancer reading homework
Think about the DNA animal you drew
(write this down) A gene is a piece of DNA that codes
for proteins. The proteins created from a gene have
a specific function for the organism.



All genes come in different forms known as
alleles.
You received two genes/alleles from your
parents– one allele from mom and the other
allele from dad.
Alleles can be either dominant or recessive


Dominant: (capital letters)– this gene/allele rules
over recessive alleles
Recessive: (lowercase letters)– this gene/allele is
overruled when paired with a dominant allele

Eye Color



Blue Eye color is a recessive allele (b)
Brown Eye color is a dominant allele (B)
What eye color will theses allele pairs show?
BB
Bb
(Brown) (Brown)
bb
(Blue)


Use the chart below to find the allele you and your
classmates possess.
We will collect the class data and create a class graph to
determine what alleles are dominant and recessive.
Trait
Eye Color
Eye Shape
Earlobe
Space Between Front Teeth
Tongue Rolling
Number of Fingers
Hair on Middle Sections of
Fingers
Chin Shape
Shape of Hairline
Dimples
Freckles
Option 1
Not Blue
Narrow/oval
Free
Space
Can roll edges
Six per hand
Hair
Option 2
Blue
Round/Circular
Attached
No space
Cannot roll edges
Five per hand
No hair
Dimple in middle
Widow’s peak
Dimples
Freckles
No dimple
No Widow’s Peak
No Dimples
No Freckles

Are you more likely to get a dominant allele or
a recessive allele from your parents? Why or
Option 1
Option 2
why not?
Eye Color (blue v non blue)
Eye Shape (narrow v round)
Ear Lobe (free v attached)
4
7
8
16
13
12
Space between front teeth (yes v no)
Tounge Rolling (yes v no)
Fingers on Hand (6 v 5)
Hair on Fingers (yes v no)
4
15
0
5
16
5
20
15
Chin Shape (dimple v non)
Hair line (widow's peak v non)
Dimples (yes v no)
Freckles (yes v no)
0
6
8
5
20
14
12
15

Are you more likely to get a dominant allele or
a recessive allele from your parent? Why or
why not?
Option 1 Option 2
Eye Color (non blue v blue)
Eye Shape (narrow v round)
16
3
3
11
Ear Lobe (free v attached)
Space between front teeth (yes v no)
Tongue Rolling (yes v no)
Fingers on Hand (6 v 5)
Hair on Fingers (yes v no)
13
2
15
0
9
2
18
4
19
9
Chin Shape (dimple v non)
Hair line (widow's peak v non)
Dimples (yes v no)
Freckles (yes v no)
2
3
2
6
17
16
19
13


Your parents each gave you an allele for a
specific gene (hair color, eye shape etc.) . The
pair of alleles is known as a Genotype.
Three different Genotypes:
BB
bb
Homozygous
(both alleles
are the same)
Bb
Heterozygous
(both alleles
are different)


The physical characteristic or trait defined by a
gene/allele is known as the phenotype.
Phenotypes for the eye color gene: blue eyes,
brown eyes, green eyes


Punnett Squares
A punnett square
uses the parent
genotype (P=parent)
to predict all the
possible offspring
(f1=first filial)
genotypes.
Monohybrid Cross

The gametes (pollen
or egg) produced by
each flower only have
half (1N) the DNA
meaning offspring
only get one of the
alleles from each
parent

Punnett sqares can make predictions for two
genotypes at once in a dihybrid cross.
What are the parent
genotypes?
SsBb

Some genes are dominant or recessive
What are the
different phenotypes
going to be?
RR= Red
Rr = Red
Rr = White


Not every gene is dominant or recessive…
What if:
RR= Red
 rr= White
 Rr= PINK?

When a heterozygous
pair have a BLENDED
phenotype the genes
have incomplete
dominance.


Not every gene is dominant or recessive…
What if:
RR= Red
 rr= White
 Rr= Red AND White?

When a heterozygous
pair have a MIXED
phenotype the genes
are codominant



Use the gene guide for dominance, codominance and incomplete dominance.
Determine the genotypes and phenotypes for
each gene pair. Check with me when finished.
Complete the lab of gummy bear crosses using
punnette squares to determine what genotypes
and phenotypes will appear in the offspring.
Record in comp book.
Match the appropriate bear to each problem.
How is sex (male or
female) determined
in humans?
The X-female and Ymale chromosomes
Female = XX
Male= XY
Deformed = -Y, X-, XYY,
XXY, XXX,

X
Y


The X and Y sex chromosomes have genes like
all other chromosomes
Because the genotype for male (XY) and female
(XX) people is different, the phenotype is
different too.

Example: Hemophilia = poor blood clotting
due to mutation on a gene found in the X
chromosome.
Genotype
Phenotype

Xh
=
recessive allele for hemophilia

XH
=
dominant allele for normal
blood clotting

Who has Hemophilia?
Female Genotypes -- Phenotypes
 XhXh
YES
 XHXH
NO
NO
 XHXh




Male Genotypes-- Phenotypes
NO
XHY
YES
XhY
The chance of
getting a recessive
Xh is 1/7000
1/7000 men have
hemophelia
1/49,000,000
women have
hemopheila


Because men only have one X chromosome,
they are more likely to show recessive
genotypes and phenotypes
Male recessive X- conditions:



Hemophilia
Red-Green Color Blindness
Male Pattern Baldness


Pedigrees are family trees that visually tell us
how genes have been passed from one
generation to the next.
We can sue pedigrees to predict if a gene is
dominant, recessive, or sex-linked.
Sex Linked?
Dominant?
Recessive?



What do you
see in the
picture?
How is each
pair
different?
Can we
actually see
genes?
Spectral Karyotype



Karyotypes examine all of the chromosomes of
an organism.
Karyotypes are useful for categorizing the
chromosomes by number and appearance.
We use karyotypes today to see how genetic
mutations change our chromosomes.

What is
different
between
this picture
and the
previous?

H H
Genotype
H


Phenotype
Karyotype

What is
wrong with
this
karyotype?

What is
wrong with
this
karyotype?

What is
wrong with
this
karyotype?
Use the karyotype sheet provided to find genetic chromosome disorders for six
different insects. Copy the chart below in your composition book to record answers.
Sex
Insect 1
Insect 2
Insect 3
Insect 4
Insect 5
Insect 6
Genetic Disorder
Chromosome
Error


Some genes have multiple alleles (multiple
dominant or recessive genes) that create greater
genotypic and phenotypic variation.
(think back to the gummy bear lab)

Blood Type: A, B, AB, o
A = dominant
 B = dominant
 AB = co-dominant
 o = recessive

Blood types tell us about the
specific antigen on the outside
of your blood cells.
Universal receiver Universal Dono
1) Homozygous A crosses with co-dominant AB

What genotypes and phenotypes appear in the
offspring?
2) Heterozygous oA crosses with co-dominant AB

What genotypes and phenotypes appear in the
offspring?



Frame Shift
Deletion
Addition