1. Human Genetic Disorders
Chapter 12 Review
Human Genetic Disorders

2. The person in this picture is a male female
This organized picture of an individual’s chromosomes is called a __________________
karyotype
The person in this picture is a
male female
Female
There are 2 X and no y chromosomes.

3. Name an X-linked genetic disorder.
The genetic disorder in which the person can’t make the protein needed to make their blood clot is called ______________________
hemophilia
Name an X-linked genetic disorder.
Hemophilia, colorblindness, Duchenne Muscular dystrophy

4. A person with trisomy-21 (three #21 chromosomes) has ____________
Amniocentesis
___________________ is a test in which a needle is inserted through the mother’s abdomen and some of the fluid surrounding the fetus is withdrawn to test for genetic problems.
A person with trisomy-21 (three #21 chromosomes) has ____________
Down syndrome

5. Males can NOT be carriers for autosomal recessive disorders.
Genetic disorder in which a person can NOT
breakdown phenylalanine and eating foods containing this amino acid causes them to become retarded.
Phenylketonuria (PKU)
TRUE or FALSE
Males can NOT be carriers for autosomal recessive disorders.
False. Males CAN carry AUTOSOMAL disorders, they just can’t be carriers for X linked disorders.

6. A group of genes carried on the same
A person who has a copy of the gene for a recessive disorder but doesn’t show any signs of the sickness is called a _________________
carrier
A group of genes carried on the same
chromosome and usually inherited together
Linkage group

7. The cell that forms when an egg and a sperm
join together is called a _______________
zygote
TRUE or FALSE
GERM cell mutations can be passed on to
Offspring.
TRUE : Germ cells are reproductive cells. Changes in the DNA of these cells is passed on to the offspring.

8. An autosomal trait is found on the X chromosome
Genetic disorder in which the DNA code for hemoglobin is changed. Red blood cells with the damaged hemoglobin protein, change into a sickle shape and clog up the blood vessels.
Sickle cell anemia
TRUE or FALSE
An autosomal trait is found on the X chromosome
FALSE Autosomes are the chromosomes that are NOT sex chromosomes.

9. A trait that is controlled by several genes
(like skin color or height) is called ______________
Polygenic
Give an example of an autosomal dominant
genetic disease.
Huntington’s ;
Achondroplasia (dwarfism)
Male pattern baldness (males)

10. Give an example of Y linked gene.
Chorionic villi sampling
_____________________ is a test in which a sample of the tissue is taken from the tissue surrounding the baby and tested to see if the fetus has any genetic disorders.
Give an example of Y linked gene.
Hairy ears (pinna)

11. A trait in which there are three or more choices
A trait carried on autosomes but affected by a person’s sex hormones (like male pattern baldness) is said to be _____________________
SEX INFLUENCED
A trait in which there are three or more choices
for a single gene (like A, B, and O blood type) is a ____________ trait.
polygenic multiple allele
multiple allele

12. Dizygotic or fraternal twins have identical DNA
TRUE or FALSE
Dizygotic or fraternal twins have identical DNA
False They come from 2 different eggs and 2 different sperm
Eye color is a _____________ trait.
Polygenic Multiple allele sex linked
polygenic

13. reattaches backwards in the strand.
The change in a single base of the DNA code is
called a ___________ mutation.
point
An _______________ happens when a piece of DNA breaks off, gets flipped around, and
reattaches backwards in the strand.
INVERSION

14. ______________ mutations cause death often before birth.
A body cell is also called a ______________ cell.
SOMATIC
______________ mutations cause death often before birth.
LETHAL

15. A person with the Xy genotype would be
male female
male
A _________ cell mutation happens in sperm or egg cells.
GERM

16. Twins which don’t separate entirely and remain attached by some body part are called ______________
Conjoined
Which person shows the
Genetic trait? A B A C

17. The mutation caused when a piece of
This picture shows a ___________________
Karyotype
Pedigree
Punnett square
pedigree
The mutation caused when a piece of
a chromosome is missing is called a ________
Addition substitution inversion deletion
deletion

18. A trait that is NOT polygenic is
A point mutation in which one base in the code is replaced with a different base is called a
Addition deletion substitution inversion
Substitution
A trait that is NOT polygenic is
Height skin color A,B,O blood type eye color
A,B,O blood type is a multiple allele trait NOT polygenic

19. A genetic mutation in which an extra base is
This is used to show possible genotypes of offspring. It is called a _______________
Karyotype Pedigre Punnett square
Punnett Square
A genetic mutation in which an extra base is
added to the DNA code is called a
Addition deletion substitution inversion
Addition (also called an insertion)

20. A B O blood type is a ___________ trait.
TRUE or FALSE
When 1 egg and 1 sperm form a zygote that splits into balls of cells, the babies will have identical DNA.
TRUE
A B O blood type is a ___________ trait.
Multiple allele polygenic sex linked
Multiple allele

21. X-linked genes _______________ Only show up in girls
Doctor’s check the level of ________________ in the mother’s blood to see if the baby’s spinal cord and brain are growing correctly.
Alpha-feto protein
X-linked genes _______________
Only show up in girls
Show up more frequently in boys
can be heterozygous in boys
only pass from mothers to daughters
Show up more frequently in males

22. Cystic fibrosis is more common in ___________
Sickle cell anemia is more common in ____________________
Males females African Americans Caucasians
African Americans
Cystic fibrosis is more common in ___________
Males females African Americans Caucasians
Caucasians

23. Twins that come from one sperm and egg are called _____________
Maternal or MONOZYGOTIC
Which person is a carrier for the trait? A B C C D

24. The genes that cause a person’s red blood cells to change into this
A mutation in which a certain piece of DNA is copied over and over is called a ____________
Deletion substitution inversion duplication
duplication
The genes that cause a person’s red blood cells to change into this
sickle shape is inherited as an
(choose 2)
Autosomal Dominant
X-linked Recessive
Autosomal recessive

25. A gene that is carried on the X chromosome
X-linked
A trait with 3 or more choices for a gene
(like A B and O blood type alleles)
Multiple allele trait

26. Sex linked genes are found on the X or y chromosome.
Twins with different DNA that come from 2 different egg and sperm are called
dizygotic or Fraternal
TRUE or FALSE
Sex linked genes are found on the X or y chromosome.
True; sex LINKED means they are on one of the sex chromosomes.

27. When homologous chromosomes don’t separate
The gene that causes male pattern baldness is
Sex linked sex influenced Y linked
Sex influenced
BB’ in males = bald
BB’ in females = not bald
It is also AUTOSOMAL DOMINANT
When homologous chromosomes don’t separate
during meiosis it is called _________________
nondisjunction

28. What mutation is it? deletion inversion translocation
Piece of DNA breaks off and is lost ____________________
Piece of DNA breaks off, flips backwards,
and reattaches ____________________
Piece of DNA breaks off and reattaches
To a non-homologous chromosome _____________________
Extra piece of DNA is added into the
sequence _______________________
One nucleotide in a codon is replaced with another _______________________
Failure of homologous chromosomes to separate during meiosis ________________________
inversion
translocation
Insertion (addition)
substitution
Non-disjunction

29. Which parent determines the sex of the baby?
thefatcat ranandran theatcatranandran
the fat cat ran and ran the atc atr and ndr an
Addition or deletion of part of the DNA code can cause the remaining codons to move up or down the line in the code resulting in a misreading of the code. This is called a ______________ mutation.
frameshift
Which parent determines the sex of the baby?
father

30. Which type of mutation can be passed along to offspring?
Somatic cell mutation Germ cell mutation
Germ cell mutation
Which of the following is NOT visible in a karyotype ?
Sex of baby
Missing or extra chromosomes a point mutation
Point mutations

31. Name 3 disorders that are:
Autosomal recessive X linked recessive
_______________ _______________
________________ _______________
Phenylketonuria (PKU)
Sickle cell anemia
Cystic fibrosis
Hemophilia
Colorblindness
Muscular dystrophy
Name 3 disorders that is caused by nondisjunction:
___________________
Down’s syndrome
Turner’s syndrome
Kleinfelter’s syndrome

32. A trait that is X linked will _____________
show up more in females than males
be carried on an autosome appear more in males than females
be carried by males
Appear more in males than females
What is the difference between a germ cell mutation and a somatic cell mutation?
Somatic cells are body cells and mutations in these cells are NOT passed on to offspring.
Germ cells are reproductive cells. Mutations in these cells CAN be passed on to offspring.

33. LOW AFP in the mom’s blood suggests what?
Chromosomal abnormality like
Down or Turner syndrome
Test that can be done earlier than amniocentesis
in which cells from the tissue around the baby are sampled and checked for genetic defects
Chorionic villi sampling (CVS)

34. How is a pedigree different from a karyotype?
Genes that are closer together on a chromosome are ______________ likely to be separated by crossing over than genes that are farther apart.
more less
less
How is a pedigree different from a karyotype?
Pedigree shows how a trait is passed along through the generations in a family;
Karyotype shows the chromosomes from just one person

35. Give an example of a MULTIPLE ALLELE trait.
ABO Blood type
Give an example of a POLYGENIC trait.
Hair color foot size
skin color nose length
eye color intelligence
height

36. HIGH AFP in the mom’s blood suggests what?
Spina bifida
Name a disadvantage of doing amnioncentesis
or chorionic villi sampling
Can cause miscarriage

37. Twins with identical DNA that come from the
same egg and sperm are called
Monozygotic or Maternal
TRUE or FALSE
Sex influenced genes are found on the X chromosome.
False; they are autosomal. They are influenced by the sex hormones of a person.

38. Name the test
Needle is inserted through abdomen and amniotic fluid containing baby cells is removed and tested ____________________
Blood test done on mother to measure level of a
protein made by the baby ___________________
Piece is removed from tissue surrounding baby
and tested for abnormalities ___________________
Cell is smashed, chromosomes are matched up,
and a picture is taken ______________________
amniocentesis
Alpha feto protein
Chorionic villi sampling
karyotype

39. Name a kind of mutation that causes a frame shift.
Deletion or insertion (any change that is not in multiples of 3)
TRUE or FALSE
Females can be carriers for X linked genes.
True; they have 2 X chromosomes. So they can have one normal gene and one mutant gene.

40. The cell that forms when an egg and a sperm
join together is called a _______________
zygote
TRUE or FALSE
Somatic cell mutations can be passed on to
offspring.
False; they are in body cells. They can make the cell unable to function; cause cancer; or kill the body cell BUT are NOT PASSED ON TO OFFSPRING.

41. How is a sex linked trait different from a sex influenced trait?
Sex linked traits are carried on sex chromosomes.
Sex influenced traits are carried on autosomes but
are affected by a person’s sex hormones.
The deletion of a single nucleotide base would
result in _________________.
nondisjunction monosomy a translocation a frame shift mutation
a frame shift mutation;
Everything gets moved over one place in the code

42. Why do X-linked recessive disorders show up
Genes that are farther apart on a chromosome are ______________ likely to be separated by crossing over than genes that are farther apart.
more less
more
Why do X-linked recessive disorders show up
more in males than females?
Males only have one X. If they get the gene it will show.
Females have a 2nd X that can “hide” the disorder gene. They need 2 copies of the gene to show disorder. Males don’t have a “back up” X.

43. Tell one way genetics in humans in MORE COMPLICATED than Mendel thought
Some traits are determined by more than one gene
(POLYGENIC)
Some traits have more than 2 allele choices
(MULTIPLE ALLELE)
Some genes are linked to other genes
Genes can move during crossing over OR
“Jump” like in corn

44. Explain why frame shift mutations at the beginning of a gene are more damaging than those at the end
Frame shift at beginning damages more of the code.

45. ________________________
A man and a woman have the same genotype for a trait, but only one of them shows the trait. This would be an example of
________________________
A sex influenced gene
Down’s syndrome is an example of _______________.
monosomy trisomy a sex linked a recessive gene mutation
TRISOMY; three of one chromosome

46. What disorder is it? Hemophilia Sickle cell anemia
Mutation in the blood clotting protein makes
person unable to stop bleeding after an injury _______________
Mutation in hemoglobin causes red blood
cells to change shape and ____________________
clog up blood vessels
Mutation causes mental retardation
if foods containing phenylalanine are eaten _____________________
Three #21 chromosomes are present
causing mental retardation _______________________
Mutation in ion channel protein causes thick mucous to clog up lungs and digestive organs _______________________
Hemophilia
Sickle cell anemia
Phenylketonuria (PKU)
Down syndrome
Cystic fibrosis

47. What disorder is it? Huntington’s disease (HD)
Gradual deterioration of the brain that appears during middle age resulting
in nursing home care and early death ____________________
Progressive weakening of muscle proteins resulting in inability to walk and eventually death _________________________
Inability to distinguish between the colors red and green _____________________
Only one X and no y chromosome ____________________
resulting in infertility
Huntington’s disease (HD)
Duchenne Muscular dystrophy
Colorblindness
Turner syndrome

48. What disorder is it? Spina bifida Conjoined twins Kleinfelter syndrome
Twins that are born joined together ____________________
Males with an extra X chromosome ______________________ (XXY) karyotype; some female features; infertility
Pattern of hair loss in which _____________________
homozygous persons(male& female) & heterozygous males lose their hair in a predictable pattern
Failure of the bone and skin to grow
correctly and cover the spinal cord __________________________
Conjoined twins
Kleinfelter syndrome
Male pattern baldness
Spina bifida

49. Dominant/recessive? Autosomal/X-linked/nondisjunction
Turner syndrome ____________________
Cystic fibrosis ____________________
Hemophilia _____________________
Colorblindness __________________
Phenylketonuria ___________________
Duchenne muscular dystrophy ________________
Autosomal recessive
X-linked recessive
X-linked recessive
Autosomal recessive
X-linked recessive

50. Dominant/recessive? Autosomal/X-linked/nondisjunction
Autosomal recessive
Phenylketonuria ____________________
Down syndrome ____________________
Sickle cell anemia _____________________
Kleinfelter syndrome ____________________
Huntington’s disease ______________________
Male pattern baldness _________________
nondisjunction
Autosomal recessive
nondisjunction
Autosomal dominant
Autosomal dominant

51. Name 3 disorders that are:
Autosomal recessive X linked recessive
_______________ _______________
________________ _______________
Phenylketonuria (PKU)
Sickle cell anemia
Cystic fibrosis
Others in book:
Tay Sach’s
Albinism
Hemophilia
Colorblindness
Duchenne
Muscular dystrophy
Others in book:
Achondroplasia (dwarfism)
Polydactyly
(extra fingers/toes)

52. Name 3 disorders that is caused by nondisjunction:
___________________
Down syndrome
Turner syndrome
Kleinfelter syndrome
XXX
Xyy
Name a SEX INFLUENCED TRAIT
_____________________
Male pattern baldness

53. Name a multiple allele trait:
__________________
A, B, O blood type
Name a POLYGENIC TRAIT
_____________________
Human height
Intelligence
Eye color
Hair color

54. Dominant/recessive? Autosomal/X-linked/nondisjunction
Phenylketonuria ____________________
Down syndrome ____________________
Sickle cell anemia _____________________
Klinefelter syndrome ____________________
Huntington’s _______________________
Autosomal recessive
nondisjunction
Autosomal recessive
nondisjunction
Autosomal dominant

55. Dominant/recessive? Autosomal/X-linked/nondisjunction
Turner syndrome ____________________
Cystic fibrosis ____________________
Hemophilia _____________________
Colorblindness __________________
Nondisjunction
Autosomal recessive
X-linked recessive
X-linked recessive