Transcript disorder - Cloudfront.net

Genetics
1. What chromosomal disorder is
caused by a piece being lost?
• Deletion
2. What chromosomal disorder is
caused by an extra piece of
chromosome being added?
• insertion
3. What chromosomal disorder is
caused by a piece breaking off &
reattaching in the opposite order?
• inversion
4. What chromosomal disorder is
caused by part of a chromosome
breaking off and attaching to
another chromosome?
• translocation
5. What chromosomal disorder is
caused when a chromosome does
not separate?
• nondisjunction
6. In what phases can
nondisjunction occur and what is
the result for the gametes?
• Anaphase I
• Anaphase II
7. Make a dihybrid cross for the
following: TtRr TTrr (T=tall;
t=short; R=red; & r=white)
•
TR
Tr
tR
tr
• Tr
TTRr
TTrr
TtRr
Ttrr
• Tr
TTRr
TTrr
TtRr
Ttrr
• Tr
TTRr
TTrr
TtRr
Ttrr
• Tr
TTRr
TTrr
TtRr
Ttrr
8. From the above dihybrid, how many
tall red flowers were produced?
• 8-TTRr & TtRr=Tall & Red
• 8-TTrr & Ttrr= Tall & White
• Equal 16 squares
•
TR
Tr
tR
• Tr
TTRr
TTrr
• Tr
TTRr
TTrr
Tall/Red
Tall/Red
Tall/Red
• Tr
TTRr
Tall/Red
• Tr
TTRr
Tall/White
Tall/White
Tall/White
TTrr
Tall/White
TTrr
TtRr
Tall/Red
TtRr
Tall/Red
Tall/Red
TtRr
Tall/Red
TtRr
tr
Ttrr
Tall/White
Ttrr
Tall/White
Tall/White
Ttrr
Tall/White
Ttrr
9. What chromosomes are
involved with autosomal conditions?
• Pairs #1-22 (all but the sex chromosomes)
10. A hypothetical disorder's location is written as
13q31.5. Answer the following questions using this
information.
What chromosome is the disorder located? • 13
10. cont. Is the disorder
above or below the
centromere?
If it said "p" instead of "q",
would it be above or below
the centromere?
31.5 represents what?
• Below
• Above
• Units above
orbelow the
centromere
11. Answer the following questions for Down's
Syndrome:
List the 4 main characteristics• Mental retardation, muscle weakness, heart defects &
short stature
•
It affects what 3 systems the most?
Brain/neurological, heart/circulatory and muscle
Which chromosome does it affect and what is
the cause?
• Chromosome 21 nondisjuntion causing trisomy 21
12.Answer the following questions for Cystic
Fibrosis:
What 2 systems does it affect?
• Lungs & digestive
Which chromosome and what type of autosomal
disorder is it?
• #7 autosomal recessive
13. Answer the following questions for Sickle Cell
Anemia:
Describe the condition• Red blood cells are crescent shaped instead of round.
This shape change does not allow them to bind to
oxygen properly
What type of autosomal disorder and which
chromosome?
• Autosomal recessive chromosome #11
14. Answer the following questions for
Huntington's Disease:
Describe the condition• Deterioration of brain tissue in middle age
(30’s & 40’s)
What type of autosomal disorder• Chromosome #4 Autosomal Dominant
15. If an offspring has an autosomal
dominant disorder, what does that tell you
about their parent?
• 1 or both parents have the disorder
16. If both parents are heterozygous with an
autosomal dominant disorder (they have the
disorder), what is the likeliness for their offspring to
have the disorder? (D=disorder & d=no disorder)
D
D
d
DD
Dd
Disorder
d
Dd
Disorder
Disorder
dd
no disorder
75% with Disorder
17. What is the likeliness for an offspring to
get an autosomal recessive disorder if both
parents have the disorder? (d=disorder &
D=no disorder)
d
d
d
dd
dd
(disorder)
d
dd
(disorder)
(disorder)
dd
(disorder)
100% disorder
18. If both parents are carriers for an autosomal
recessive disorder (they do not demonstrate the
condition), what is the likeliness of the offspring
getting the condition. What about the likeliness of
being a carrier? (d=disorder & D=no disorder)
D
D
d
DD
Dd
no disorder
d
Dd
carrier
Disorder =1/4 or 25%
Carrier= ½ or 50%
carrier
dd
disorder
19. How can an autosomal
recessive condition be hidden for
generations?
• The dominant allele hides it
20. What chromosome number do
sex-linked chromosomes occur on?
• Pair #23
21. Which chromosome do most
sex-linked conditions occur and
why?
• X
• Larger & carries more genes
22. What type of chromosome does
mothers give their offspring? Their
fathers?
• Mother gives only “X’s” to their offspring
• Fathers give X’s to daughters & Y’s to sons
23. Who determines the offspring's sex?
• Father
24. Answer the following
about Colorblindness:
DescriptionWho is most commonly
affected-
• Can’t distinguish
certain colors
• Males
Type of sex-linked disorder- • X-linked recessive
25. Answer the following about Hemophilia:
Description• Blood does not clot
Who is most commonly affected• Males
Type of sex-linked disorder• X linked recessive
26. Answer the following about
Turner Syndrome:
• Females short in
Descriptionstature, no puberty,
or menstruation
Who is most commonly • Females
affected & chromosome
combination• X0-only 1
What type of sex-linked
chromosome
disorder• Nondisjunction
27. Answer the following
about Klinefelter's
Syndrome:
•
DescriptionWhat type of sex-linked
disorder & chromosome •
combination-
Hermaphroditic male
& female reproductive
organs but only 1
functional
NondisjunctionXXY(usually)
28. Who is more affected by X-linked
recessive disorders and why?
• Males because they only have 1 X-sex
chromosome & girls have a 2nd X which if
dominant can mask the disorder
29. If a mother has a disorder,
what is the likeliness her son will
have it too?
• 100%-mother gives the son his only X & if
she only has affected X’s-then he will have
disorder
30. If a daughter has a disorder,
which parent(s) contributed the
chromosome?
• Both
31. Describe the 3 types of genetic screening
and the method used to analyze them?
1. Blood tests
2. Amniocentesis-draw fluid from sac
3. Chorionic Villi Sampling-testing tissue from between
uterus & placenta
4. Karyotyping-taking tests & arranging the chromosomes
into homologous pairs by size & shape
32. What is the benefit of pedigree
charts?
• To view heredity and characteristics
33. What type of allele can a
carrier have but not show the
condition?
• recessive
34. What type of chromosomal
disorder can males not be a
recessive carrier for?
• X linked