1. UNIT 9 – THE HUMAN GENOME

2. I. HUMAN GENETICS (pp. 311-313) A. Human Somatic Cells
________ cells are ______ or __.
Each cell contains ___ chromosomes, or ___ pairs of chromosomes.
Of the pairs, ___ are ____________, contain the same genes in the same order, and are called ____________.
diploid
body 2n 46 23 22
homologous
autosomes

3. A. Human Somatic Cells sex XX
The 23rd pair of chromosomes are the ____ chromosomes.
Female =___
Male= ___.
sex XX XY

4. B. Human Gametes n
Gametes are _______, or __, and contain ___ chromosomes.
Female gametes are _____ cells made in the ___________ in the process of __________.
Male gametes are ______cells made in the _________ in the process of __________.
haploid 23
egg
ovaries
meiosis
sperm
testes
meiosis

5. B. Human Gametes Egg cell can only contain an __ chromosome
Sperm cell produced has a ___% chance of containing a ___ and a ___% chance of containing an __.
The _____ determines the sex of the offspring. X 50 Y 50 X
male

6. C. Analyzing Human Chromosome Numbers
Nondisjunction - Abnormal numbers of chromosomes in ______ result in genetic disorders called ___________.
____________, which means ______________.
gametes
number disorders
nondisjunction
“not coming apart”

7. C. Analyzing Human Chromosome Numbers
A chromosome pair fails to separate correctly in ________ so the gametes produced have an abnormal _____________________.
Number disorders are not inherited; therefore, they cannot be predicted with ________________.
anaphase
number of chromosomes
Punnett squares

8. C. Analyzing Human Chromosome Numbers
Karyotypes –
A karyotype is a photograph of ________________.
Cells are stopped during _________ and are stained, photographed, and the photograph is enlarged.
chromosome pairs
mitosis

9. C. Analyzing Human Chromosome Numbers
The chromosomes are cut out and arranged in ____________ pairs in size order, with the ____ chromosomes making up the 23rd pair.
Used to detect _________ disorders and to determine the ________ of an unborn child.
homologous
sex
number
gender

10. C. Analyzing Human Chromosome Numbers
They do not detect abnormal _______; therefore, a normal karyotype does not guarantee a ______ child!
genes
normal

11. II. HUMAN GENETIC DISORDERS – NUMBER DISORDERS (pp. 313-314)
A. Autosomal Number Disorders
Most are _____.
The only autosomal number disorder that allows survival into adulthood is ___________________.
lethal
Down syndrome

12. Is there a problem with this karotype

13. Autosomal Number Disorders Down syndrome
known as __________ because there are ___ chromosomes at the ____ position, instead of ___.
Individuals have characteristic facial features; growth, behavior, and mental development are all affected
trisomy 21 3
21st 2

14. Autosomal Number Disorders Down syndrome
There is also a higher risk of _________ heart defects.
The incidence of babies with Down syndrome is much higher in ______ mothers.
congenital ol
older

15. Is there a problem with this karyotype?

16. B. Sex Chromosome Number Disorders
1. Turner Syndrome
Called ______
because individuals lack __________________.
_______, typically ______ in stature, underdeveloped sexually, ______, with a normal life expectancy.
45 XO
2nd sex chromosome
female
short
sterile

17. Does this individual have a number disorder?

18. B. Sex Chromosome Number Disorders
2. Klinefelter Syndrome
Called ________.
Symptoms do not appear until ________ at which time affected _________ show poor sexual development and infertility.
Treated with __________. Normal life expectancy.
47 XXY
puberty
males
testosterone

19. III. ANALYSIS OF HUMAN INHERITANCE
A. Punnett Squares & Multiple Alleles (pp. 304)
multiple alleles; that is, ___________ alleles.
An example of this is ABO blood groups. There are ____ alleles for this gene. Two of the alleles, _______ are co-dominant, meaning ______________ if present. The third allele, ____, is recessive, meaning it will only show if the genotype is ___.
more than 2 3
A and B
they always show
i (o) ii

20. . Punnett Squares & Multiple Alleles2
Each individual inherits ___ alleles for this gene, one from _____ and one from ____.
mom
dad

21. Punnett Squares & Multiple Alleles
The possibilities for blood group genotypes and phenotypes are:
Phenotypes Genotypes
Type A blood _____________
Type B blood _____________
Type AB blood _____________
Type O blood _____________
I I or I i A
I I or I i B
I I A B ii

22. Complete ABO Blood Type Punnetts in Notes packet

23. B. Pedigrees (pp. 299-301) trait generations squares circles shaded
A pedigree is a diagram that follows the inheritance of a single _____ through several ____________ of a family.
Males are represented by ________
Females, by _______.
Individuals with the trait are represented with ________ figures.
trait
generations
squares
circles
shaded

24. B. Pedigrees Individuals shown with unshaded figures
_________________.
Vertical lines connect _______ and _______.
Horizontal lines connect _________ or _________.
Children are placed in __________,from _________.
do not show the trait
parents
children
spouses
siblings
birth order
left to right

25. Complete pedigrees in note packet

26. IV. INHERITED HUMAN GENETIC DISORDERS
Gene Mutations
______________________________.
Causes Inherited human genetic disorders
a change in the DNA sequence of the gene

27. IV. INHERITED HUMAN GENETIC DISORDERS
B. Types of Inherited Genetic Disorders
1. Autosomal Genetic Disorders – Gene mutation is on any chromosome other than ________________
2. Sex-Linked Disorders – Mutated gene is on the ____ chromosome.
sex chromosomes X

28. VI. GENETIC DISORDERS - AUTOSOMAL DISORDERS
autosomes
Most genes are carried on the ___________, ______ chromosomes other than the sex chromosomes.
Most genetic disorders are ___________ disorders.
These disorders affect males and females ________ and are due to _____ mutations. 44
autosomal
equally
gene

29. Autosomal disorders can be divided into three groups based on the pattern of inheritance.
1. Autosomal Recessive
2. Autosomal Co-Dominant
3. Autosomal Dominant

30. A. Autosomal Recessive Disorders (pp. 297)
1. Albinism – Characterized by failure to produce pigment, __________. Affected individuals lack coloration in ______, _____, and _____. Very susceptible to ___________. Symptoms appear __________; _________ life expectancy
melanin
eyes
skin
hair
UV light
Normal
at birth

31. A. Autosomal Recessive Disorders
2. Cystic Fibrosis – Characterized by excess __________________in _______, _________system. Symptoms appear just after birth and include frequent respiratory infections, poor nutrition. With treatment, patients can survive to young adulthood. Cystic fibrosis is the most common _______ genetic disorder in the ________ among Caucasians.
mucus production
lungs
digestive
fatal
United States

32. B. Autosomal Co-Dominant Disorders (pp. 303)
Sickle cell anemia is an autosomal co-dominant disorder that affects __________ production.
Hemoglobin is the protein that binds ________ to red blood cells.
hemoglobin
oxygen

33. Sickle cell Anemia
Individuals with the normal genotype, AA, do not have the sickle cell allele and produce only normal Hemoglobin.

34. Sickle cell Anemia
Individuals that are SS produce abnormal hemoglobin that causes the red blood cells to “sickle” when oxygen availability is decreased;
for example, in high altitudes or during periods of stress. Sickled RBCs are more fragile, easily destroyed – results in lack of ________ due to decreased _____ production in cells, blockage of blood vessels, and severe pain. Shortened life expectancy. Most common inherited disease in individuals of ______ ancestry.
energy
ATP
African

35. Sickle cell Anemia
Heterozygotes (AS) produce both normal and abnormal hemoglobin and are said to have ________________. They do not show symptoms of the disorder. In certain areas, individuals with sickle cell trait have a benefit over individuals that lack the sickle cell allele because they are resistant to _______. Malaria is a serious, sometimes fatal disease spread by __________ that affects millions of people each year in _______. This increased malarial resistance has resulted in a very high incidence of AS individuals. If two heterozygotes marry and have children, they have a ___% chance of having a child with sickle cell anemia.
sickle cell trait
malaria
mosquitoes
Africa 25

36. C. Autosomal Dominant Disorders (pp. 298)
1. Huntington’s Disease – Fatal genetic disorder in which symptoms do not show until ______________. Characterized by deterioration of _____________.
2. Achondroplasia - ___________
30s to 40s
nervous system
Dwarfism

37. V. GENETIC DISORDERS - SEX-LINKED DISORDERS (pp. 305-308)
A. Sex-Linked Inheritance
“Sex-linked” if it is located on a sex chromosome (______).
In humans, sex-linked genes are almost always located on the larger ___ chromosome.
The __ chromosome is much smaller and carries only a few genes related to ________________________.
X or Y X Y
male sexual development

38. A. Sex-Linked Inheritance (pp. 305-308)2
Females have __ X chromosomes;
males have ____.
Females will only show recessive traits located on the X chromosome if they are ________________________.
Males will always show a recessive trait located on the X chromosome because he only has _____ X chromosome,
so all _______ on the X chromosome will show.
This results in _________ having a much higher incidence of sex-linked disorders.
one
homozygous recessive
one
genes
males

39. Sex-Linked Inheritance 1. Genotypes
Genotypes for sex-linked traits are written using the X and Y chromosomes to show path of inheritance.
For example, male-pattern baldness is a sex-linked recessive trait. If H = normal head of hair and h = baldness, bald male = _____; bald female = _____.
Females can be _______ for sex-linked recessive disorders. A carrier has the defective allele, but ______________. The genotype of a female carrier is ______.
Males _______ be carriers for sex-linked traits because their 2nd sex chromosome is the _______!
X Y h
X X h
carriers
it does not show
X X h H
cannot
naked Y

40. 2. Sex-Linked Punnett Squares
In sex-linked traits, probabilities for male
and female offspring must be calculated
separately because traits are
________________.
If a man with a full head of hair marries a
woman who is heterozygous, what is the
probability they would have a son who would
go bald? A daughter?
inherited differently

41. Sex-Linked Punnett Squares-
If a man with a full head of hair marries a woman who is heterozygous, what is the probability they would have a son who would go bald? A daughter?
Key: __________________
Cross: _________________
Probability of bald daughter = ________
Probability of bald son= ___________

42. B. Sex-Linked Disorders
All of these disorders are sex-linked ___________________.
1. Color Blindness – Inability to differentiate and distinguish ___________________.
recessive
colors

43. Left Right Top 25 29 Spots Middle 45 56 Bottom 6 8
Results For Ishihara Test(above)
Normal Color Vision
Red-Green Color Blind
Left
Right
Top 25 29
Spots
Middle 45 56
Bottom 6 8

44. B. Sex-Linked Disorders
2. Hemophilia – Missing an enzyme required for normal ____________ - results in _____________________. Treated with blood transfusions, injections of missing factor.
blood clotting
uncontrolled bleeding

45. B. Sex-Linked Disorders
3. Duchenne’s Muscular Dystrophy – Symptoms develop at ___________. Muscles ____________________, leading to eventual death. No available
__________ or ______. Death usually occurs before adulthood.
3-6 years
weaken, break down
treatment
cure

48. Examples:
A colorblind female marries a man with normal vision. What is the probability of colorblind children?
Key: ______________
Cross: ______________
Probability of colorblind daughter: _______
Probability of colorblind son:________

49. 2. A genetics counselor interviews a couple with a family history of hemophilia to evaluate the possibility of offspring with the disorder. The woman does not have hemophilia, but states that her father had the disorder. The man is normal. Key:_____________ Cross: ____________ Son with: _________ daughter with: ______