Download Mendelian Genetics/Exceptions/Karyotypes

TEKS 6 D & F
Mendelian Genetics
Pedigrees & Karyotypes
TAKS Objective 2 – The student will demonstrate an understanding of
living systems and the environment.
TEKS Science Concepts 6 D & F
The student knows the structures and functions of nucleic acids in the
mechanisms of genetics. The student is expected to
(D) compare genetic variations observed in plants and animals
(A) identify and analyze karyotypes.
TAKS Objective 2
page 1
TEKS 7.9 A
For Teacher’s Eyes Only
Mendelian Genetics
Pedigrees
Karyotypes
Student Prior Knowledge
Students should be familiar with the components associated with body systems
TEKS 6.10 (C) identify how structure complements function at different levels of
organization including organs, organ systems, organisms, and populations and the
functions of these systems.
TAKS Objective 2
page 2
TEKS 7.9 A
Mendelian Genetics
5 E’s
ENGAGE
Comical X and Y Chromosome Maps
Comic relief and fun discussing differences on the X and Y chromosome maps.
EXPLORE
Explore 1
Fundamentally Genetics
In groups of two, students will look at each other to determine whether
they are dominant or recessive for specific, identifiable traits.
Explore 2
Bugs, Bugs, Bugs
Genes for traits are encoded and arranged linearly on structures called
chromosomes found in the nuclei of most cells. When organisms
reproduce, the resulting offspring should receive an equal number of
chromosomes from the mother and the father.
In this activity students will use the chromosomes and Bug Traits Key to
determine the genotype and phenotype of the offspring.
TAKS Objective 2
page 3
TEKS 7.9 A
Explore 3
Begin Wisconsin Fast Plants Genetics Lab
Explore 4
Predicting Outcomes of One Trait Crosses
Monohybrid Punnett Squares
Upon completion of this activity, students will be able to predict the
outcomes of various monohybrid crosses.
Predicting Outcomes of Two Trait Crosses
Dihybrid Punnett Squares
What predictions can be made when looking at two traits. Students will
complete this activity to predict the outcomes of various dihybrid crosses.
EXPLAIN
Complete the Mendelian Genetics PowerPoint presentation with your student
with discussion and the completion of the following questions.
ELABORATE
Elaboration 1
Exceptions to Mendel’s Rules
Students will complete various Punnet squares problems that will involve the
following types of inheritance: Sex-Linked, Multiple Alleles, Co-Dominance,
Incomplete Dominance
TAKS Objective 2
page 4
TEKS 7.9 A
Elaboration 2
Who’s the Parents?
Obtain WARD’S Scientific lab kit Simulated ABO Blood Typing Lab Activity
from www.wardsci.com Item #36 V 0022
Upon completion of this lab, students will:
determine the ABO blood types of two sets of parents and two
newborn children
examine the genetic relationships possible between the parents and
children
match the “mixed up” children with their proper parents.
EVALUATE REWRITE
1.
TAKS Objective 2
page 5
TEKS 7.9 A
TAKS Objective 2
page 6
Biology
Fundamentally Genetics
TAKS Objective 2
page 7
Biology
Bugs, Bugs, Bugs
TAKS Objective 2
page 8
Biology
Predicting Outcomes of One Trait Crosses
Monohybrid Punnett Squares
The Punnett Square:
The Punnett square is a chart, used by geneticists, to help determine the chances
of an offspring receiving a particular characteristic. The Punnett square will not
tell you how many offspring will develop, or the order in which they will be born.
B = brown hair and b = blonde hair.
Example: ----------Bb X Bb ---------Parents who are heterozygous for Brown hair.
Gametes: ----------B and b ; B and b-------Each parent produces 2 gametes.
Punnett Square:
Gametes -------|---->
B
b
--------------------------------- ---------------------B
----------------------
---------------------
B
1. What are the chances of the offspring being homozygous brown haired?
____________.
2. What are the chances of the offspring having blonde hair?
__________________.
3. What are the chances of the offspring being heterozygous brown haired?
___________.
4. What is the genotypic ratio? _________________.
5. What is the phenotypic ratio? ________________.
6. What is the dominant gene? _________________.
TAKS Objective 2
page 9
Biology
7. Is there a heterozygous blonde haired offspring? ___________. Why?
__________________________________________________________________
__________________________________________________________________
Questions:
8. If curly hair is dominant to straight hair, what letters will we use to show these
genes?
9. If a heterozygous curly haired male marries a straight haired female, what
would there genotypes look like using the letters in question 8 ?
________________X _________________.
10. What would be the gametes for the male parent? ____________________
11. What would be the gametes for the female parent? ___________________
12. Work out the Punnett square in the space below and answer the following
questions.
Gametes -------|---->
B
b
--------------------------------- ---------------------B
----------------------
---------------------
B
13. What are the chances of the offspring being homozygous curly haired?
___________________.
14. What are the chances of the offspring having straight hair?
__________________.
15. What are the chances of the offspring being heterozygous curly haired?
____________.
16. What is the genotypic ratio? _________________.
17. What is the phenotypic ratio? ________________.
18. What is the dominant gene? _________________.
TAKS Objective 2
page 10
Biology
19. Is there a heterozygous straight haired offspring? ___________.
Why?_____________________________________________________________
__________________________________________________________________
20. If yellow pods are dominant to green pods, what letters will we use to show
these genes?
21. If a heterozygous yellow male is crossed with another heterozygous yellow
female, what would there genotypes look like using the letters in question 20 ?
________________X _________________.
22. What would be the gametes for the male parent? ____________________
23. What would be the gametes for the female parent? ___________________
24. Work out the Punnett square in the space below and answer the following
questions.
Gametes -------|---->
B
b
-------------------------------- ---------------------B
----------------------
---------------------
B
25. What are the chances of the offspring being homozygous green?
________________.
26. What are the chances of the offspring being yellow? __________________.
27. What are the chances of the offspring being heterozygous yellow?
________________.
28. What is the genotypic ratio? _________________.
29. What is the phenotypic ratio? ________________.
30. What is the dominant gene? _________________.
TAKS Objective 2
page 11
Biology
31. Is there a heterozygous green offspring? ___________. Why?
__________________________________________________________________
__________________________________________________________________
TAKS Objective 2
page 12
Biology
Predicting Outcomes of Two Trait Crosses
Dihybrid Cross
Independent Assortment: Mendel's 4th Law explains that , when gametes are
formed, genes move into these gametes independently of other genes. This occurs
only if these genes are on different chromosomes.
Dihybrid Cross: A genetic problem with two different characteristics.
T = Tall, t= short.---------B = brown hair, b = blonde hair
Parents: TTBB-- X ttbb
Gametes:
TB
-tb
Punnett Square:
Gametes
tb
TB
TtBb
Notice that each parent produces gametes with 2 genes, one from each pair. Never
do we have more than one gene from each pair in a gamete. We are now going to
mate two of the offspring produced in the above problem.
Parents: --- -TtBb ---X -- TtBb
Gametes:- TB---
TB
Tb -
-Tb
tB
tB
tb
tb
TAKS Objective 2
page 13
Biology
Punnett Square:
Gametes
TB
Tb
tB
tb
TB
TTBB TTBb TtBB TtBb
Tb
TTBb TTbb TtBb Ttbb
tB
TtBB TtBb -------- --------
tb
-------- -------- -------- ttbb
a). What is the phenotypic ratio: ________________________________
b). What is the genotypic ratio?
_____________________________________________.
Problem:
Cross a homozygous tall, heterozygous brown haired male with a heterozygous
tall, blonde haired female.
--------------------------- --__________________X ____________________
Gametes: ----------------------____________ -------------______________
Gametes: ----------------------____________ -------------______________
Gametes: ----------------------____________ -------------______________
Gametes: ----------------------____________ -------------______________
Punnett square:
Gametes
TB
Tb
tB
tb
TB
TTBB TTBb TtBB TtBb
Tb
-------- -------- -------- --------
TAKS Objective 2
page 14
Biology
tB
-------- -------- -------- --------
tb
-------- -------- -------- ttbb
a). What is the phenotypic ratio ? ____________________________
b). What is the genotypic ratio ? ____________________________
c). How many offspring are homozygous for both characteristics ?
_______________.
d). How many offspring are heterozygous for both characteristics ?
_________________.
TAKS Objective 2
page 15
Biology
Mendelian Genetics Guided Notes
Mendel and Genetics
Directions: Answer the following questions completely.
1. The _________________________ is a chart, used by geneticists, to help
determine the chances of an offspring receiving a particular characteristic.
2. Before parents can mate successfully, each one must produce special cells
called _________________.
3. These special cells contain ______________ the normal number of
chromosomes of regular body cells.
4. ________________________ is considered the father of Genetics.
5. DNA contains the code for every ____________________ that an organism
can produce.
6. According to Mendel, ______________ pairs separate during gamete
formation.
7. Mendel called traits that appeared more often than its alternate
____________________.
8. This trait or characteristic is assigned a(n) _________________ letter to
distinguish it from its recessive allele.
9. If two alleles for a characteristic are identical, the organism is said to be
_________________________ for that trait.
10. Another word for hybrid is ___________________________.
11. The ____________________ is the outward appearance of an organism’s
trait.
12. Tt or BB represents the _______________________ of an organism.
13. An alternate form of a gene is called its __________________________.
TAKS Objective 2
page 16
Biology
Read the following problem, solve it by working out the Punnett square, and then
answer the questions that follow.
Mate a rooster that is homozygous for curly feathers with a hen that is
heterozygous for straight feathers. Straight feathers are dominant to curly
feathers.
1. Choose a letter to represent the allele curly feathers ___________ and one for
the allele straight feathers __________.
2. Write out the genotypes of each parent below:
______________ X _______________
3. List the gametes for each parent: _____ _____ and ____ ____
Show all work for full credit.
Gametes -------|---->
B
b
--------------------------------- ---------------------B
----------------------
---------------------
B
4. What are the chances of the offspring having curly feathers?
__________________.
5. What are the chances of the offspring having straight feathers?
__________________.
6. What is the genotypic ratio? _________________.
7. What is the phenotypic ratio? ________________.
TAKS Objective 2
page 17
Biology
8. Being able to roll your tongue into a u shape is caused by a dominant gene. The
recessive allele does not allow this to happen. Two parents, one with the ability to
roll her tongue and the other one cannot roll his, mate and have two children. All
of the children cannot roll their tongues. What is the genotype of each parent?
______________and _______________.
Mendel tried to determine if green seed color was dominant to yellow seed color.
The result of the experiment is found below. Examine the data, bar graph it, and
answer the questions that follow.
Generation of
Plants
Number of Yellow Seeds
Produced per generation
Number of Green Seeds
Produced per generation
P
0
0
F1
0
100
F2
102
312
F3
303
879
F4
970
2900
F5
2,970
9,080
TAKS Objective 2
page 18
Biology
Graph Title:
___________________________________________________________
TAKS Objective 2
page 19
Biology
1. What color appears to be the dominant allele? _______________________.
2. Why?
________________________________________________________________
__________________________________________________________________
3. What is the phenotypic ratio of the above experiment?
______________________.
4. What is the dependent variable?
____________________________________________.
5. What is the independent variable?
__________________________________________.
6. Explain why the F1 generation contained all green seeds.
__________________________________________________________________
_____________________________
7. What was the genotype of the F1 generation? ___________________.
__________________________________________________________________
TAKS Objective 2
page 20
Biology
Exceptions to Mendel’s Rules
Multiple Alleles, Co-Dominance, Incomplete Dominance
Incomplete Dominance
Sometimes the masking effect of a dominant allele (gene) is not complete. This is
evident in the case of the red and white 4 o'clock flower. If we mate a
homozygous red flower (RR) with a homozygous white flower (WW), we would
expect all the offspring to be red. Instead all of the flowers came out pink. Red did
not completely mask the white allele. The red gene allows the production of red
pigment, if it is in a homozygous condition. The white gene does not allow
pigment production. If one R gene is present, half of the pigment is produced and
a pink color appears. The genotype for pink colored flowers is RW. This
condition also occurs in cattle, where the individual with the genotype RW is
called a roan.
Define incomplete dominance
__________________________________________________________________
______________________________________________
Give two characteristics that are governed by incomplete dominance?
__________________________________________________________________
TAKS Objective 2
page 21
Biology
Example -------------------------------------RR ------X------WW
Punnett Square:
Gametes W
W
RW RW
R
RW RW
R
1. What are the chances of having pink offspring ? ___________________.
2. What are the chances of having red offspring ? __________________.
3. What are the chances of having white offspring ? __________________.
4. What is the genotypic ratio ? _________________.
5. What is the phenotypic ratio ? ________________.
6. A farmer wants to mate two roans together. What are the genotypes of the these
animals ? _____________ X _________________
7. What would be the gametes for the male parent ? ____________________
8. What would be the gametes for the female parent ? ___________________
9. Work out the Punnett square in the space below and answer the following
questions.
Gametes -------|---->
B
b
--------------------------------- ---------------------B
----------------------
---------------------
B
TAKS Objective 2
page 22
Biology
10. What are the chances of having red offspring ? ___________________.
11. What are the chances of having white offspring ? __________________.
12. What are the chances of having roans ? __________________.
13. What is the genotypic ratio ? _________________.
14. What is the phenotypic ratio ?
__________________________________________________________
15. What information would let a person know that a characteristic is governed by
incomplete dominance?
__________________________________________________________________
__________________________________________________________________
TAKS Objective 2
page 23
Biology
Multiple Alleles and Co-Dominance
16. Define multiple alleles.
__________________________________________________
__________________________________________________.
17. What are the genotypes for Blood type A? ____________________, Type B?
________________________, and Type O? ______________________.
18. What is the genotype of the universal donor?
____________________________
19. A man with heterozygous B type blood marries a women with heterozygous A
blood. What are the chances of them having children with type A blood?
__________, Type B blood? _____________, O type blood? _____________.
Work out the problem below.
Punnett Square:
Gametes -------|---->
B
B
--------------------------------- ---------------------B
----------------------
---------------------
b
20. Of the three alleles for blood type which two are codominant?
____________________.
21. At a local hospital, Mr. and Mrs. Lump had a child at the same time as Mr.
and Mrs. Bump. The Lumps had a boy and called him Bill, while the Bumps also
had a boy and called him Tony. A few weeks past and the Bumps claimed the
babies were switched. They sued the hospital and all 6 individuals were asked to
get their blood tested. The results of the tests were: Mr. Lump had A type blood,
his wife had B type blood, and Bill had A type blood. Mr. Bump tested for O type
blood, his wife had AB blood, and Tony had O type blood. Was there a switch?
_________. How do you or do you not know?____________________________
TAKS Objective 2
page 24
Biology
Work the punnett square for each of the parents below:
The Bumps: ________ X ________.
Gametes -->
B
b
The Lumps: _________X________
Gametes -->
----------------------------------------------------B
B
b
--------------------------------- ---------------------B
----------------------
---------------------
B
------------------B
TAKS Objective 2
page 25
Biology
--- ---------------------
Who’s the Parents?
Inheritance Patterns of Blood Types
Use the provided documents from the Ward’s science kit.
TAKS Objective 2
page 26
Biology
Pedigrees and Karyotypes
5 E’s
ENGAGE
Pedigrees
Read the short story Alexis: The Prince Who Had Hemophilia –by:-Kelley, Laureen A.
Set in the early 1900s, this is the story of the youngest child of Tsar Nicholas II of Russia, last
Tsar of Russia. The story includes how Alexis's haemophilia influenced the course of events in
Russia that led to the Russian Revolution. (Ages 8 to adult.)
Cost: FREE
www.kelleycom.com
Kelley, Laureen A., 1992
LA Kelley Communications, Inc.
68 East Main Street, Suite 102
Georgetown, MA 01833
(978) 352-7657
Complete the PowerPoint presentation and discussion of the spread of hemophilia
through the Royal Family. The history and pedigrees will engage students in
predicting inheritance patterns. Have student complete the Sex Chromosomes
hand out in the Blackline Masters before continuing with karyotypes.
Karyotypes
Show students various normal and abnormal karyotypes with their corresponding
diseases and symptoms.
TAKS Objective 2
page 27
Biology
EXPLORE
Explore 1
Sex-Linked Inheritance (Blackline Masters)
Explore 2
What Do You Know About Diabetes?
Obtain this kit from www.sciencekit.com item number WW4810600. This
activity will review covered information over the digestive system and allow
students to a different aspect of diabetes. Students compare a “normal” DNA
strand with one that has a mutation known to cause diabetes. They then test
solutions with glucose test strips to determine the glucose levels of each, examine
the disorder from a Mendelian perspective (pedigrees), workout a diet according
to NIDDK guidelines, and investigate techniques used to determine if a person
carries the genes for diabetes. Developed by Bill Humphries.
Explore 3
Analyzing Chromosomes
Students will correctly identify and analyze the chromosomes of a normal male
and female.
EXPLAIN
Complete the Karyotyping and Pedigrees PowerPoint presentation with your
student with discussion and the completion of the following questions.
TAKS Objective 2
page 28
Biology
ELABORATE
Elaboration
Pedigrees
Students will analyze and draw conclusions from various pedigrees that they
will draw.
Clues from the Karyotype
Order photomicrographs of chromosomes spreads from www.sciencekit.com.
Students will become “geneticists” by identifying, organizing and studying
human chromosomes to determine if any chromosomal disorder is present in
their patient. Order numbers: WW6062301, WW6062401, WW6062501,
WW6062601, WW6062701, WW6062801.
EVALUATE REWRITE
TAKS Objective 2
page 29
Biology
TAKS Objective 2
page 30
Biology
Sex Chromosomes
1. What are the two sex chromosomes? ________________ and
________________.
2. In order for an individual to be a male he must contain the ___________ and
__________ chromosomes.
3. A female's sex chromosomes are ____________and ______________.
4. Of the male and female , the ______________ is responsible for the sex of their
offspring.
5. Mate a male (XX) with a female (XY). Answer the questions that follow:
Gametes -------|---->
B
b
--------------------------------- ---------------------B
----------------------
---------------------
b
6. What is the possibility of producing a boy? ___________________.
7. What is the phenotypic ratio? _________________________.
8. If a family contained 5 children, 3 boys and 2 girls, what is the chance of
having another girl? ___________________.
9. Explain what happens to a person with Turner's syndrome.
__________________________________________________________________
__________________________________________________________________
10. Who can get Turner's syndrome?
__________________________________________
11. Explain the cause of Kleinfelter's syndrome:
__________________________________________________________________
_________________________________________________________________
TAKS Objective 2
page 31
Biology
12. Can girls get Klienfelter's syndrome? ___________. Explain
__________________________________________________________________
13. How can an individual get Down's syndrome?
__________________________________________________________________
__________________________________________________________________
14. What are sex-linked genes?
_______________________________________________
15. What sex chromosome is the largest? _______________
16. Which sex chromosome contains the most genes? ______________
17. Name 2 sex-linked diseases.
______________________________________________
18. What is the genotype of a carrier female for Hemophilia?
________________________
19. Mate a normal male and a carrier female for Hemophilia. Use the Punnett
square below to show your work.
XHY x XHXh
Gametes -------|---->
20.
B
b
--------------------------------- ---------------------B
----------------------
---------------------
b
What are the chances of having a normal boy? ________________.
21. What are the chances of having a normal girl? __________________.
22. What are the chances of having a hemophiliac boy? ________________.
TAKS Objective 2
page 32
Biology
Sex-Linked Characteristics
1. Determine the possible blood types from the cross of a person who is
homozygous A blood type and a person who is heterozygous B blood type.
Show you work here:
_______________________ X _______________________
Female
Gametes
Male
_____________________
_____________________
______
______
_____________________ _____________________ _____________________
______
______
______
_____________________ _____________________ _____________________
______
______
______
2. Humans contain __________ sex chromosomes.
3. Of these sex chromosomes the _________ determines the sex of the child.
4. A gene found on the sex chromosome is called a(n) ________________ gene.
5. Define the term carrier female. _____________________________________
______________________________________________________________.
6. Name two sex-linked conditions. ___________________________________
TAKS Objective 2
page 33
Biology
7. Cross a carrier female and a normal male in the space below.
_______________________ X _______________________
Female
Gametes
Male
_____________________ _____________________
______
______
_____________________ _____________________ _____________________
______
______
______
_____________________ _____________________ _____________________
______
______
______
8. What are the chances of their offspring having the disease hemophilia?
____________.
9. What are the chances of their sons being normal? ______________.
10. What are the chances of their daughters being a carrier? ______________.
11. Cross a colorblind male and a carrier female.
_______________________ X _______________________
Female
Gametes
Male
_____________________ _____________________
______
______
_____________________ _____________________ _____________________
______
______
______
_____________________ _____________________ _____________________
______
______
______
12. What are the chances that their sons will be colorblind? ____________.
13. What are the chances that their daughters will be carriers? __________.
14. If a woman's father had hemophilia, what are the chances that she is normal?
______________
TAKS Objective 2
page 34
Biology
15. Explain your answer.
__________________________________________________________________
__________________________________________________________________
__________________________________________________________________
__________________________________________________________________
16. If her mother was a carrier, what are the chances that she is normal?
____________, a carrier? _______
17. Explain why are there more males with sex-linked problems than females?
__________________________________________________________________
__________________________________________________________________
__________________________________________________________________
18. What is a karyotype?
__________________________________________________________________
__________________________________________________________________
19. Name some chromosomal abnormalities detected through the use of
karyotypes.
__________________________________________________________________
__________________________________________________________________
Cat color is a sex linked trait. Yellow is the dominant allele while black is
recessive. The heterozygous condition results in a mixed coat color refered to as
calico. A calico cat is mated to a black cat. What are the chances of them
producing calico males? _______________.
_______________________ X _______________________
Female
Gametes
Male
_____________________ _____________________
______
______
_____________________ _____________________ _____________________
______
______
______
_____________________ _____________________ _____________________
______
______
______
WHAT DO YOU KNOW ABOUT DIABETES?
Use the handouts provided in the ordered kit.
TAKS Objective 2
page 35
Biology
Pedigrees
Follow the directions below and draw each pedigree.
1.
a. Generation I : A male with blood type O marries a female with blood type A.
b. Generation II : They have 4 children. The first born is a male with A type
blood, the second born is a girl with O type blood, and the last two children were
identical twin boys.
c. Generation III : The last boy married a women with type B blood. They had
two girls, one with AB blood type and one with B blood type.
TAKS Objective 2
page 36
Biology
2.
a. Generation I : A man with dark brown hair marries a women with blond hair.
b). Generation II : They have 5 children. The first born is a girl, who marries a
man with blond hair, the second and third child are boys with blond hair. The
remaining 2 children were girls , both with brown hair.
c). Generation III : The first born girl has 3 girls, all of which have blonde hair. Is
it possible for them to have children with brown hair? Explain.
__________________________________________________________________
__________________________________________________________________
TAKS Objective 2
page 37
Biology
3.
a. Generation I : A farmer mates a roan bull with a red cow.
b. Generation II: Over a period of 5 years three roan cows and 2 red bulls were
born in that order.
c. Generation III : The first roan was mated to a white bull and had 4 calves. The
first one was a white bull while the other 3 were cows.
TAKS Objective 2
page 38
Biology
Analyzing a Normal Karyotype
TAKS Objective 2
page 39
Biology
Clues from the Karyotype
Use the handouts and directions provided in the ordered kit.
TAKS Objective 2
page 40
Biology