1. UNIT 9 – THE HUMAN GENOME
Quiz Friday 1-27
Test Friday
2-3-16

2. I. HUMAN GENETICS (pp. 341-343) A. Human Somatic Cells
Human somatic cells (____ cells) are ______ or __. Each cell contains ___ chromosomes, or ___ pairs of chromosomes. Of these pairs of chromosomes, ___ pairs are ____________ pairs, meaning they contain the same genes in the same order.
body
diploid 2n 46 23 22
homologous

3. A. Human Somatic Cells sex XX
The 44 chromosomes that make up the 22 homologous pairs in each cell are called _________. The 23rd pair of chromosomes are the ____ chromosomes. In female somatic cells, the sex chromosomes are ___; in a male’s cells, the sex chromosomes are ___.
autosomes
sex XX XY

4. B. Human Gametes n
Gametes are _______, or __, and contain ___ chromosomes. Female gametes are _____ cells and male gametes are ______cells. Gametes are produced through the process of ________ in the _______ or ______, respectively.
haploid 23
egg
sperm
meiosis
ovaries
testes

5. B. Human Gametes
In meiosis, when the ___________ pairs of chromosomes separate in ___________, the sex chromosomes separate also. The resulting egg cell can only contain an __ chromosome, while the sperm cell produced has a ___% chance of containing a ___ and a ___% chance of containing an __. Therefore, the _____ determines the sex of the offspring.
homologous
anaphase I X 50 Y 50 X
male

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

7. Nondisjunction
In Anaphase I if homologous pairs do not separate correctly
In Anaphase II if sister chromatids do not separate correctly
In either case, Gametes are produced with an abnormal number of chromosomes.
Number disorders are not inherited; therefore, they cannot be predicted with Punnett squares.

8. C. Analyzing Human Chromosome Numbers
2. Karyotypes - A karyotype is a photograph of ____________________.
Cells from the developing embryo or individual being tested are cultured in a nutrient growth medium, and then chemically treated to stop _________ in metaphase. The cells are stained, the chromosomes 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. Karyotypes can only be 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. 352, 353)
A. Autosomal Number Disorders
Most autosomal number disorders 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
Down syndrome is also known as __________ because there are ___ chromosomes at the ____ position, instead of _______.
trisomy 21 3
21st 2

14. Down Syndrome

16. Autosomal Number Disorders Down syndrome
Individuals have characteristic facial features; growth, behavior, and mental development are all affected. There is also a higher risk of _________ heart defects. The incidence of babies with Down syndrome is much higher in ______ mothers.
congenital
older

17. Patau Syndrome (Trisomy 13)

18. Trisomy 13 Cleft lip or palate
Clenched hands (with outer fingers on top of the inner fingers)
Close-set eyes -- eyes may actually fuse together into one
Extra fingers or toes (polydactyly)
Hole, split, or cleft in the iris (coloboma)
Low-set ears
Mental retardation, severe
Scalp defects (missing skin)
Seizures
Single palmar crease
Skeletal (limb) abnormalities
Small head (microcephaly)
Can have 3 types
One extra 13th chromosome in all cells
Trisomy 13 mosaicism-Extra 13 only in some cells, caused by mitosis after fertilization
Partial Trisomy-due to translocation presence of a part of extra chromosome 13 in all cells

20. Edwards or Trisomy 18

21. Edward’s Syndrome (Trisomy 18)
Symptoms
Clenched hands
Crossed legs (preferred position)
Feet with a rounded bottom (rocker-bottom feet)
Low birth weight
Low-set ears
Mental deficiency
Small head (microcephaly)
Small jaw (micrognathia)
Underdeveloped fingernails
Undescended testicle
Unusual shaped chest (pectus carinatumTrisomy 18 is a relatively common syndrome. It is three times more common in girls than boys. The syndrome is caused by the presence of extra material from chromosome 18. The extra material interferes with normal development.
Can also be Full Trisomy 18, Partial Trisomy 18, or Mosaicism

23. Is there a problem with this karyotype?

24. B. Sex Chromosome Number Disorders
1. Turner Syndrome
Also called ______ because individuals lack __________________. Affected individuals are _______, typically short in stature, underdeveloped sexually, with a normal life expectancy.
* Generally infertile
45 XO
2nd sex chromosome
female

25. Turner’s Syndrome

26. Does this individual have a number disorder?

27. B. Sex Chromosome Number Disorders
2. Klinefelter Syndrome
Also 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

28. Klienfelter’s
Syndrome

29. III. ANALYSIS OF HUMAN INHERITANCE
A. Punnett Squares & Multiple Alleles (pp )
A multiple alleles gene has that is, ___________ alleles. An example of this is ABO blood groups. There are ____ alleles for this gene.
more than 2 3

30. . Punnett Squares & Multiple Alleles (pp. 345-346)
A and B
_______ are co-dominant, meaning ______________ if present. The third allele, ____, is recessive, meaning it will only show if the genotype is ___.
they always show
i (o) ii

31. ABO Blood Types

32. Punnett Squares & Multiple Alleles (pp. 345-346)
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

33. B. Pedigrees 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 ________ and females, by _______.
Individuals with the trait are represented with ________ figures.
trait
generations
squares
circles
shaded

34. B. Pedigrees
Vertical lines connect _______ and _______. Horizontal lines connect _________ or _________.
Children are placed in __________,
from _________.
parents
children
spouses
siblings
birth order
left to right

35. IV. INHERITED HUMAN GENETIC DISORDERS
Gene Mutations
Inherited human genetic disorders are the result of gene mutations; that is, ______________________________.
a change in the DNA sequence of the gene

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

37. V. GENETIC DISORDERS - SEX-LINKED DISORDERS
A. Sex-Linked Inheritance (pp.350, 351)
A gene is referred to as “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.350, 351)2
one
Females have __ X chromosomes; males have ____. Females will only show recessive traits located on the X chromosome if they are ______________________. But a male 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.
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.
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. Male Baldness

41. 2. Sex-Linked Punnett Squares
In sex-linked traits, probabilities for male
and female offspring must be calculated
separately because traits are inherited differently.
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?

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. Gene Therapy for Hemophilia

46. 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

47. DMD

50. VI. GENETIC DISORDERS - AUTOSOMAL DISORDERS (pp. 345-348)
Most genes are carried on the ___________, ______ chromosomes other than the sex chromosomes. These disorders affect males and females ________ and are due to _____ mutations. Autosomal disorders can be divided into three groups based on the pattern of inheritance.
autosomes 44
equally
gene

51. Autosomal Recessive Disorderd
Albinism
Characterized by failure to
produce pigment,_____________
2. Very susceptible to __________________
melanin
UV rays

52. Autosomal Recessive Disorders
Cystic Fibrosis
Characterized by excess _______________ in ________, _________________system.
Symptoms appear just after birth and include frequent respiratory infections poor nutrition.
With treatment, patients can survive into adulthood.
Most common_____________genetic disorder in the _______________________ among Caucasians.
mucus
lungs
digestive
fatal
United States

53. Cystic Fibrosis Gene

54. Phenylketonuria or ________
PKU
Characterized by an inability to breakdown the amino acid, _______________________
If untreated, results in severe mental retardation
All babies born in US hospitals are tested for PKU because it is easily treated with a diet low in ___________________
Phenlyalanine
proteins

56. Autosomal Co-Dominant Disorders
Sickle cell anemia is an autosomal
co-dominant disorder that affects ________________ production. Hemoglobin is the protein that binds _________________
to red blood cells.
hemoglobin
oxygen

57. Sickle Cell Anemia AA
Individuals with the normal genotype do not have the sickle cell allele and produce only normal hemoglobin.

58. Sickle Cell Anemia 2. SS Sickle Cell Anemia
Produce abnormal hemoglobin that causes the red blood cells to “sickle” when oxygen availability is decreased; for example, in high altitudes or during period of stress.
Sickled RBCs are more fragile, easily destroyed-results in lack of ___________due to decreased _______________ in cells, blockage of blood vessels, and severe pain.
energy
oxygen

59. SS Shortened life expectancy.
Most common inherited disease in individuals of _______________ ancestry.
African

60. 3. AS heterozygous Described as _____________________
Produce both normal and abnormal hemoglobin
Do not typically show symptoms of the disorder.
Heterozygote Advantage-Provides resistance to __________________
malaria

61. C. Autosomal Dominant Disorders
Huntington’s Disease
Fatal genetic disorder in which symptoms do not show until _______________________
Characterized by deterioration of
Middle age m
Mental functions and
uncontrollable movements

62. Achondroplasia
Dwarfism
________________ (one form)

63. Marfan Syndrome
Marfan syndrome- Dominant disorder that affects the connective tissue of the skeletal system, eyes, and circulatory system.
Affected individuals have very long limbs, vision problems, and are susceptible to aortic rupture.

65. Marfan Syndrome