Download Dihybrid Problems

Name _________________________ Date ________ Hour _____
HW due Friday October 23rd
Lab
Beaker
Babies
Lab
Pedigree
Analysis
EXTRA
HW
Pedigree
HW
dihybrid
Due:_______________
Data Table
Drawing
Due:_______________
Data Table
Analysis
T.V. Show Pedigree
HW Peidgree
0 1 2 3
0 1 2 34
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0 1
Can earn: 0 1 2 3
0 1
1
2
4
2
2
3
5
3
Page 8
Page 9
Page 10
Do in class
0 1 2
0 1 2
Page 11
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Do in class
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Genetic
Disorder #2
Your Points
Total Points Possible (25 pts)
1
Imaginary Beaker Babies
Objective: To show the workings of the gene and chromosome and their pairing to determine the
characteristics of an offspring.
Pre-lab Discussing: It must be realized that half of the chromosomes and genes an organism
possesses was inherited from the female parent and the other half came from the male parent if the
organisms was produced sexually.
Procedure A:
1. Get together with your partner (spouse) at your lab station.
2. You should have 3 beakers at your lab station, one marked female (P1), one male
(P2) and the other marked offspring (F1). If they are not marked, take a marker and
mark each one.
P1(parent 1) X P2 (parent 2)
=
F1
(offspring)
3. Each of you are going to create an imaginary beaker baby (make it up) using the
characteristics listed below. Choose the letters (genotypes) you’d like your offspring to
inherit and place the genes on your chromosome (be sure one of you is male and the
other is a female).
Genotypes and Phenotypes for imaginary Beaker Babies: DATA
A. Sex
B. Hair Color
C. Eye color
D. Height
E. Size of feet
F. Mouth shape
G. Teeth
H. Body shape
I. Blood Rh factor
J. Blood Type
K. length of mouth
L. shape of nose
M. Size of ears
N. Size of eyes
O. Shape of head
P. Hair texture
Q.
XX = female
BB = Black
EE = brown
TT = 18 cm
FF = 4 cm
RR = round
PP = Sharp
LL = Round
+ = postive
A = Type A
MM = 3 cm
NN =
ZZ = large
KK = Quarter
DD = Rectangular
CC = curly
XY = Male
bb = blonde
ee =blue
tt = 10 cm
ff = 2 cm
rr = heart shaped
pp = none
ll = square
- = negative
B = Type B
mm = 1 cm
nn =
zz = small
kk = penny
dd = Circle
cc = straight
O = Type O
R.
S.
T.
U.
V.
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HYPOTHESIS: For hair color and eye color predict the probability of your offspring
looking like their mother. What is the probability of the offspring of having the same
genetic makeup?
Speculate the logic of the probabilities for being this way?
4. Cut the male and female chromosomes along the dotted lines for each genotype
(not centromere) and place all the “genes” for male and female into the correct
beakers marked male and female beakers.
5. Randomly pull out one of each type of gene (letter A-V) from both the male and
female beakers. Use only the first of each gene drawn to form your gamete. Place it
in the offspring beaker to create one complete chromosome. So, there is a mixture of
male and female genes in the offspring beaker.
6. Put the two new chromosomes together by pairing up the letters (starting with A and
ending with V) and record them in Data Table 1 (your child). This is how you will
determine both the genotype and the phenotype for your first offspring.
Procedure B:
1. Draw your child offspring (F1) from procedure A you formed in the space provided
on the next page.
Questions:
1. Were all of your traits the dominant traits?
2. Did you have a “twin” in class that had all of your same alleles (traits)?
3. Why do you think that there was no other person just like you in class?
4. Propose a hypothesis explaining why the ring finger-index finger trait is different in males and
females.
5. If a trait is dominant does that mean that most people have that trait?
6. Define:
Allele –
Trait –
Gene –
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Eye Line
Sex
Blood
Type/ Rh
factor
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Lab– Pedigree Analysis
Background:
Pedigrees provide a powerful tool for genetic counselors. These tables help us to find the genotypes of
individuals from observable phenotypes. Before the advent of modern DNA analysis pedigrees were
one of the only ways available to determine many genotypes. With the development of DNA analysis
pedigrees provide an alternate method to find genotypes. With the genotype data we can use genetics
to determine the likelihood of having a child with a given phenotype.
Procedure A:
1. Use the pedigrees and under each symbol write the two letters that symbolize that individual’s
genotype. Remember that if we cannot be certain of an allele we must put a question mark for
that letter.
Problems:
2. Several members of a family have been diagnosed with diabetes (D or d). Use this pedigree to
determine the genotypes of each member and prove if diabetes is dominant or recessive.
3. Is diabetes dominant or recessive? Describe in detail how you know.
4.
Use this pedigree of red hair (R or r).
5. Is red hair dominant or recessive? Describe in detail how you know.
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6. If individuals II2 and II3 were to have another child what would the chance of having a child
without red hair be?
Pedigree:
Create a pedigree using the information listed below on a separate sheet of paper. For Extra Credit:
Determine the famous 70, 80’s & 90’s T.V. show families used in this pedigree.
Starting with Bill and Clair who wed in 1932 had four children. The oldest was a girl named Denise,
next came a boy named Theo, followed by his sister Vanessa. The baby in the family was Rudy.
In 1957, Theo married Carol. They had six children. First was Greg, then came Marcia, then Peter,
then Jan, they youngest boy was Bobby and finally Cindy.
Denise was first married to Jerry before she caught him with his secretary, they had two children: First
was Richie and then Joanie. After the divorce, she married Bob and they had three children: First
Becky, then Darlene and then the Baby D.J.
Vanessa married Michael and they had four children: First was a boy named Alex, then came a girl
named Mallory, next was Jennifer and the youngest boy was Andrew.
Rudy married Ross and they had twin boys named Chandler and Joey. They also had triplets named
Monica, Rachel and Phoebe.
The fourth generation is pretty small, so far…..
Jan married the housekeeper Toni and they had two children: the oldest was Samantha and the
youngest was Johnathan.
Finally, Alex married Norma and had two sons: The oldest was Wayne and the youngest was Kevin.
Part B of pedigree: Unfortunately, there is a genetic disorder found within this family’s pedigree.
The genetic disorder is X-linked for red/green colorblind. The following individuals have been found
to have the genetic disorder red/green colorblind. Theo, Jerry, Baby D.J., Chandler, Joey, and
Johnathan. Make sure to write the X’s and Y’s in your pedigree to determine who is a carrier or who
has the disorder.
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HW Biology - Genetics
Pedigree Analysis:
For each pedigree you must list what traits are dominant and recessive and which letters are
used for each. Number each individual within a generation from right to left as I1, I2, etc. Each
individual must have a genotype written, remember if you are not absolutely sure of a genotype
put a ‘?’.
1. This is a pedigree for brown eyes.
I
II
III
2. This is a pedigree for fructosuria:
I
II
III
If II3 and II4 were to have another child, what are the chances that this child would have
fructosuria?
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3. This is a pedigree for cystic fibrosis:
I
II
III
If II3 and II4 were to have another child what are the chances that this child would have cystic
fibrosis?
4. This is a pedigree for achondroplasia (dwarfism):
I
II
III
Explain what might have happened to II5.
Explain how two individuals with achondroplasia could have a child of normal height.
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5. This is a pedigree for red hair:
I
II
III
6. This is a pedigree for color blind (x-linked):
I
II
III
If II3 and II4 have another child what are the chances that they will have Adult on-set Diabetes?
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Blood Type Review
A. Cross blood type O with purebred blood type A.
1.
2.
3.
4.
5 & 6.
7.
B. Cross a heterozygous Rh+ woman with an Rh- man.
1.
2.
3.
4.
5 & 6.
7.
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Dihybrid Problems
A. Cross a totally heterozygous tall and green pea plant with a totally homozygous tall and green
pea plant.
1.
2.
3.
4.
5 & 6.
7.
B. Cross a homozygous Tall pea plant with hybrid green leaves with a heterozygous tall plant with
yellow leaves.
1.
2.
3.
4.
5 & 6.
7.
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C. Cross a homozygous red petal rose without thorns with a totally heterozygous white petal rose
with thorns.
1.
2.
3.
4.
5 & 6.
7.
D. Cross a heterozygous tall poodle with homozygous curly fur and a homozygous short poodle
with hybrid straight fur.
1.
2.
3.
4.
5 & 6.
7.
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E. Cross a heterozygous wrinkled and a homozygous green leafed lettuce plant with a homozygous
smooth and heterozygous red leafed lettuce plant.
1.
2.
3.
4.
5/6.
7. What are the genotypes, phenotypes and probabilities for their offspring?
F. List the possible gametes we could make from each genotype.
Cross out any repetitions.
bbtt: __________, __________, __________, __________
BbTt: __________, __________, __________, __________
Bbtt: __________, __________, __________, __________
AB: __________, __________, __________, __________
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My assigned genetic disorder is
GENETIC DISORDER PROJECT ASSIGNMENT #2 –
Remember, your audience for this brochure is either someone who has just been
diagnosed as having this genetic disorder or someone who is the parent or child of
someone who has been diagnosed. Your teacher will show you examples of good
brochures so you can be familiar with the qualities you should include in your brochure.
1. How common is this disorder?
2. How long do people usually live with this disorder? You may want to search terms
such as “life expectancy”.
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