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Review for Final please feel free to ask addi3onal ques3ons at any 3me! 1. Analyze phenotypic data and deduce pa3erns of inheritance from family histories. 2. Describe the molecular anatomy of genes and genomes. 3. Describe the mechanisms by which an organism’s genome is passed on to the next genera@on. 4. Describe the phenomenon of linkage and how it affects assortment of alleles during meiosis. 5. Extract informa@on about genes, alleles, and gene func@ons by analyzing the progeny from gene@c crosses. 6. Compare different types of muta@ons and describe how each can affect genes and the corresponding mRNAs and proteins. 7. Interpret results from molecular analyses to determine the inheritance pa3erns and iden@@es of human genes that can mutate to cause disease. Homologous chromosomes have a.  The same genes, but not necessarily the same sequence b.  The same genes with the same exact sequence c.  Different genes Meiosis I Meiosis II The two chromosomes represented by this green “X” are: a.  Homologous (have exactly the same gene3c material) b.  Homologous (similar but not iden3cal gene3c material) c.  Sisters (have different gene3c material) d.  Sisters (have similar but not iden3cal gene3c material) e.  Sisters (have exactly the same gene3c material) gametes Below is a karyotype of a genetically normal female. The
karyotype was made from cells undergoing metaphase of
mitosis. The circle contains how many units of DNA (consider
a “unit” to equal one double stranded DNA)
A.  1
B.  2
C.  4
D.  6
E.  8
#1
#1
A
#2
Q
A
A a
Q
Qq
a
q
a
#2
q
The cell above is a normal cell in the human body, with 4 of 46 chromosomes shown. The cell to the leO is an example of: a.  This cell in Interphase b.  This cell in Metaphase of Mitosis c.  This cell in Metaphase of Meiosis 1 d.  A daughter of this cell in Metaphase of Meiosis II e.  An en@rely different cell; no rela@onship to star@ng cell The cell to the right is a normal cell in the human body , with 4 of 46 chromosomes shown. The cell below is an example of: a.  This cell in Interphase b.  This cell in Metaphase of mitosis c.  This cell in Metaphase of meiosis 1 d.  A daughter of this cell in Metaphase of meiosis II e.  An en@rely different cell; no rela@onship to star@ng cell B B f f B
#1
f
#1
#2
b
#2
f
If two plants are crossed together in which the genotypes of both are Tt, what is the chance that an offspring will not be 3? a.  100% b.  75% c.  50% d.  25% e.  0% Rod is a carrier for two recessive disease alleles, DdEe. His wife is a carrier of just one disease allele, but has the other disease, Ddee. What is the chance that their child will be a carrier for both diseases? a.  0 b.  ¼ c.  ½ d.  ¾ e.  1 Homer AaBb x aabb Marj AaBb Bart The genes represented by A/a and B/b are closely linked on the same chromosome. Look at Bart’s genotype. What can you conclude about the gametes that Homer produced to make Bart? A.  aB & Ab gametes were more likely than AB & ab gametes B.  AB & ab gametes were more likely than aB & Ab gametes C.  aB, Ab, AB, & ab gametes were equally likely D.  You cannot determine rela3ve frequency from the informa3on given Homer AaBb x aabb Marj AaBb Lisa The genes represented by A/a and B/b are closely linked on the same chromosome. Now think about Lisa. When she produces gametes, what can you conclude? A.  aB & Ab gametes will outnumber AB & ab gametes B.  AB & ab gametes will outnumber aB & Ab gametes C.  aB, Ab, AB, & ab gametes will be present in equal numbers D.  You cannot determine rela3ve frequency from the informa3on given Sam and his wife Maggie are concerned about the inheritance of two disease-­‐ causing genes that run in their family. The two genes are 8 map units apart on the same chromosome. They are both carriers for the b allele, but are normal with respect to the A allele. Sam's genotype is B A while Maggie's is b A b A B A What is the chance they'll have a child affected with the disease caused by the b allele? a. 25% b. 21% c. 8% d. 4% e. 2% What if Sam and Maggie had different genotypes? (genes are s@ll 8 m.u. apart) Sam: A B Maggie: a B a b A b What’s the chance that their child will be aabb? What mode of inheritance is possible in the
pedigree shown below? There could be carriers
that are unmarked.
a) autosomal recessive
b) autosomal dominant
c) x-linked recessive
d) x-linked dominant
e) autosomal or x-linked recessive
Based on the pedigree above, which inheritance paYern can be ruled out? There could be carriers that are unmarked. a.  Autosomal dominant b.  Autosomal recessive c.  X-­‐linked dominant d.  X-­‐linked recessive e.  None of the above W What mode of inheritance is being shown here?
a.  X linked recessive
b.  X linked dominant
c.  Autosomal dominant
d.  Autosomal recessive
e.  mitochondrial
What will the children of the affected women in generation III
look like (assume they have children with normal, non-carrier
males)?
a.  They will be normal and not carriers
b.  They will be normal, but will be carriers
c.  Some of them will have the disease
d.  All of them will have the disease
A couple has a child with Down’s syndrome (3
copies of chromosome 21). The mother is
Bb for a recessive phenotype of cardiac
arrhythmia on chromosome 21, and the
father is BB. If genotype of the patient is
BBb, in which parent did nondisjunction
happen?
a. In the mother
b. In the father
c. It could have happened in either parent
Jeff is genotype QqDd for two genes on two different chromosomes. AOer meiosis, Jeff produces a sperm that has genotype Qdd. When did the nondisjunc@on event occur to create this sperm? a. During meiosis I b. During meiosis II c. It could have happened during meiosis I or II If you have a double stranded DNA molecule comprised of 50% cytosine, what propor@on of the molecule would be thymine? a.  Cannot be determined b.  75% c.  50% d.  25% e.  0% If you are given one strand of DNA as follows: 3’ AGCTAAC 5’ what is the sequence of the complete strand of DNA? a. 5’ TCGATTG 3’ b. 5’ GTTAGCT 3’ c. 3’ AGCTAAC 5’ 5’ TCGATTG 3’ d. 5’ AGCTAAC 3’ 3’ TCGATTG 5’ Which of the following would be the correct product of transcrip3on from this DNA? coding strand 5’ ATGTGGCAC 3’ template strand 3'TACACCGTG 5’ a.  3'ATGTGGCAC5' b.  5'ATGTGGCAC3' c.  3'AUGUGGCAC5' d.  5'AUGUGGCAC3' e.  3'UACACCGUG5' Which of the following would be the correct RNA product of transcrip3on from this DNA? 5’ TTGTGGCAC 3’ template strand 3’ AACACCGTG 5’ coding strand a. 
b. 
c. 
d. 
e. 
3’TTGTGGCAC5’ 5’TTGTGGCAC3’ 3’UUGUGGCAC5’ 5’UUGUGGCAC3’ 3’AACACCGUG5’ Where does the ribosome start “reading” the messenger RNA? a. At the very beginning of the RNA b. At the “AUG” codon c. Wherever the ribosome happens to bind along the RNA AUG-start of translation (on the mRNA)
Transcription start
5’
3’
TF RNA promoter
polym
erase 3’
gene
Sequence of DNA, showing start and stop of transcription
Transcription
Termination
5’
If a person has many copies of a par3cular protein whose structure is changed from normal, where did this change most likely originate? a.  In the DNA sequence of the gene b.  In the mRNA sequence c.  In the amino acid sequence normal muta@on A T A
A T T
U A U
U A A
tyr
Stop What about the mutation shown above? What is the result?
a.  Transcription is stopped by this mutation
b.  Translation is stopped by this mutation
c.  Both a and b
d.  Neither a. nor b. is true, but the amino acid is changed
e.  None of the above: the amino acid is the same
Point mutations can lead to a stop= “nonsense”
= shortened protein
Mutations do NOT stop transcription
If the gel below shows DNA samples from two people, one who is genotype Dd and has myotonic dystrophy, the other from a normal person, dd. Myotonic dystrophy is caused by an inser3on in the gene. Which individual has the disease? A. 
B. 
C. 
D. 
Individual I-­‐1 Individual I-­‐2 Both individuals could be affected There is no way to tell from this informa3on The cys3c fibrosis gene, when isolated by PCR, can then be cut with the restric3on enzyme HINDIII into 3 fragments, 10, 5 and 2 Kb in size 10 5 2 One of the muta3ons that causes cys3c fibrosis is a missense that changes the second cut site so that the restric3on enzyme no longer cuts at that site. If samples from some pa3ents are run on a gel, which of the gels correctly represents what would be seen if the pa3ent had cys3c fibrosis? a. 10 Kb 7 Kb 5 Kb 2 Kb b. c. d.