The Human Genome
Unit Exam
Please answer the following questions as best as you can. Select the best answer for each or fill in
the blank to complete the sentence. For the essay questions, write as much as you need to in order to
answer the question. For true false questions, if false, correct the statement.
1. Humans without chromosomal defects have this many chromosomes.
a. 43
b. 46
c. 64
d. 44
2. A picture of chromosomes arranged and grouped together in pairs to be studied by scientists is
called a _karyotype___.
3. __sex___ __chromosomes_ are the chromosomes that determine an individual’s sex. The
other 44 chromosomes are termed _autosomes___.
4. Illustrate the normal two letter chromosomal representation for malesX_ _Yand for females XX.
5. In the space provided, construct a pedigree that shows three generations. Include that the
parents in the first generation have three offspring, one male and two female. In the second
generation, show that the male is affected by a certain disease. In the third generation, show
that these offspring each have children of their own, a boy and a girl each. In only the first set of
grandchildren, show that both the male and female are affected.
6. Explain the difference between dominant and recessive genes. Give an example of a dominant
gene and of a recessive gene.
Dominant genes are expressed, recessive are not. Dominant ex =brown eyes over blue
eyes recessive. Other examples acceptable
7. Define codominance. What is an example of a disease that is codominant?
Both alleles can be expressed. Sickle cell disease
8. Traits can be influenced by other factors besides genes environmental factors. These factors can
specifically include:
a. Diet and exercise
b. Location of where one lives
c. Culture
d. All of the above
9. If a person is blood type A they have a(n) ___ antigen on their red blood cell.
a. A
b. B
c. A and B
d. No antigen
10. T/F: If you are blood type AB, it is safe to get a transfusion from a person who is type O
True
11. What is the human genome project?
a.
b.
c.
d.
A project where humans have analyzed the human DNA sequence.
A project where investigators sequenced the genomes of fruit flies and yeast
An ongoing effort headed by Drs’ Collins and Venter
All of the above
12. One way to find DNA used in the Human Genome project was to find DNA sequences known
as_________________.
a. Demolitions
b. Promoters
c. Intron
d. Exon
13. How might this DNA sequencing affect your life? How might this information evolve in the
future as more and more discoveries are made?
Dna sequencing can tell us if we carry a certain disease. It can also evolve into something much
more serious such as predetermining traits before birth.
14. How can DNA analysis be used to diagnose disorders? Why is this important?
It can be used to determine what part of the DNA is malfunctioning. It’s important so that the
disorder or disease may be diagnosed and properly treated. It can also be important for those
related for their own health.
15. ___Cystic_ _Fibrosis__ is a disease represented by symptoms of excess mucus in the lungs,
digestive tract and liver. Also, it causes an increased susceptibility to disease. This autosomal
disorder is caused by a (circle one) Dominant/Recessive/Codominant allele.
16. _Sickle__ _Cell____ disease is one that is caused by (circle one)
Dominant/Recessive/Codominant allele. Symptoms include misshapen red blood cells among
others.
17. The cell compensates to the extra X chromosome in female calls by randomly inactivating one X
chromosome. This chromosome is called a:
a. Golgi body
b. X Body
c. Barr Body
d. Extra body
18. Define nondisjunction. What happens if this occurs during meiosis?
Means “not coming apart” and if this happens, abnormal numbers of chromosomes may occur
in gametes and a chromosomal disorder can result.
19. The most common form of trisomy occurs on chromosome 21. If this happens, the disorder is
called:
a. Klinefelter’s syndrome
b. Down Syndrome
c. Tay sachs
d. Karyotype
20. Other disorders occur on the sex chromosomes. One occurs in females that only inherit one X.
this disorder is called __Turner’s__ _Syndrome__.
21. ALS aka Lou Gehrig disease is located on which chromosome?
a.
b.
c.
d.
19
20
21
22
22. Explain Gene therapy in your own words in two to three sentences.
Gene therapy is the ability to locate and replace a malfunctioning or missing gene. This way the
body can create the correct protein it needs and can eliminate a disorder.
23. What are some problems with gene therapy? Either opinion or any unknowns in the field.
It is unknown how long this beneficial effect can last
24. What are some costs and benefits of gene mapping? Why?
Gene mapping is beneficial in that it can warn those who are affected with serious diseases like
cancers to have family be cautious for the certain disease. One cost might be that it might one
day be taken to an extreme like changing gametes to have desired traits.
25. What is your stance on information acquired by DNA being submitted to the government?
Support your reasoning with research used from your debate.
Answer depends on students. Points as long as fully supported.
26. A diploid zygote is also known as what?
a. A chromosome
b. A fertilized egg
c. Sperm
d. Two haploids
27. Draw a punnet square in which a Female with a homozygous phenotype for short hair mates with a
heterozygous male. If long Hair (S) is dominant, what percent of the offspring will have long hair?
e.
S
S
S
SS
SS
s
Ss
Ss
Half (50%) will have long hair.
28. If you are phenotype O blood type and give blood at a donation center, what blood type is it
safe to give a transfusion to?
a. A
b. AB
c. O
d. B
e. All of the above
29. Identify the disease by the symptoms presented.
Patient A is a newborn that has been put on a low phenylalanine diet. This diet is intended to
prevent accumulation of phenylalanine in tissues as well as abnormal skin pigment and mental
retardation. What disorder is caused by this recessive allele.
a. Albinism
b. Achondroplasia
c. Hypercholesterolemia
d. PKU or Phenylketonuria
30. In males, nondisjunction causes _Klinefelters__ _Syndrome_ where an extra X chromosome
interferes with meiosis and usually prevents them from reproducing.
31. Which sex chromosome is essential for survival and embryo development?
a.
b.
c.
d.
X
Y
Z
X and Y
32. _DNA__ _Fingerprinting_ can be used to determine whether blood, sperm, or other material
found at a crime scene matches DNA from a suspect.
33. MrNA coding sequence or _______ are interrupted by introns.
a.
b.
c.
d.
Introns
Exons
Promoters
Stop codons
34. ________ are non coding regions.
a. Introns
b. Exons
c. Promoters
d. Stop codons
35. T/F: males have one X chromosome so X-Linked alleles are expressed in males, even if they are
recessive.