MCB 140 Exam 1
Spring 2025
You have 120 min to work on the exam. Please print your name on each page of
the exam. You can use pen or pencil, but please make sure that your writing is
visible. Keep in mind that the exams will be scanned for grading on Gradescope
and if we can’t properly scan what you write we can’t read/grade it either.
WIRELESS DEVICES OF ANY SORT ARE NOT PERMITTED! Please look over
the entire exam, so you don’t spend too much time on hard questions, leaving easy
questions unanswered. Please check your answers to make sure that they make
sense. To help us give partial credit, show your work and briefly state any
assumptions that you make.
Best of luck!! YOU GOT THIS.
Question 1 ( 30 points) ............
Question 2 ( 30 points) ............
Question 3 ( 20 points) ............
Question 4 ( 20 points) ............
Question 5 ( 35 points) ............
Question 6 ( 15 points) ............
, Name:
. The pedigree below shows
Question 1. Huntington's disease is an autosomal dominant disorder
is a particular blood antigen,
inheritance of Huntington's disease in a family. Also present in this family
for the blood antigen are
which is a recessive trait. The Huntington's disease locus and the locus
and squares represent XY
located on chromosome 4 and are 5 cM apart. Circles represent XX
in the families shown.
individuals. Assume complete penetrance and that no new mutations occur
% %afiected with Huntington’s disease
. .exhibits recessive blood antigen
None of the individuals shown below are both affected with Huntington’s
disease and exhibit the blood antigen.
4+ WY Individual | Genotype
a + 1“ L 1 a+ | a+
=)
a + e 2 +H/+tHR or +H[++
3 " 3 a+/+H
A 2 . a+ | a+
(o)) = a +
i 7 —
P
+ H ° a 1t
e (1 through 4). If there is
a. (4 points) Indicate the genotype of each individual shown in the pedigre
individual. Use + for wild-
more than one possibility, write down all the possible genotypes for a given al shown
each numbered individu
type allele for a given gene. Please write down the genotype next to
antigen. o @ points, escl-
in the pedigree. H: allele for Huntington's disease, a: allele for the blood
g+=Hpe
probability that the indicated grandchild (shown as "?") will develoé3
b. (4 points) What is the
Huntington’s disease? Show your work.
0x Hu O +I
83 1S o +/H9wbpe
Cien
W HD.
1|2 clence ol deelopd)
*Hj 12
e
T
4 {4+ tH
(shown as "?") will both exhibit the
c. (6 points) What is the probability that the indicated grandchild
your work.
recessive blood antigen and develop Huntington’s disease? Show
= |/?_9 = S
Xs FLreg belreen O‘RH)
I’(“H) 2w *x'2 = Hluo = 092>
Y’
Spring 2025
You have 120 min to work on the exam. Please print your name on each page of
the exam. You can use pen or pencil, but please make sure that your writing is
visible. Keep in mind that the exams will be scanned for grading on Gradescope
and if we can’t properly scan what you write we can’t read/grade it either.
WIRELESS DEVICES OF ANY SORT ARE NOT PERMITTED! Please look over
the entire exam, so you don’t spend too much time on hard questions, leaving easy
questions unanswered. Please check your answers to make sure that they make
sense. To help us give partial credit, show your work and briefly state any
assumptions that you make.
Best of luck!! YOU GOT THIS.
Question 1 ( 30 points) ............
Question 2 ( 30 points) ............
Question 3 ( 20 points) ............
Question 4 ( 20 points) ............
Question 5 ( 35 points) ............
Question 6 ( 15 points) ............
, Name:
. The pedigree below shows
Question 1. Huntington's disease is an autosomal dominant disorder
is a particular blood antigen,
inheritance of Huntington's disease in a family. Also present in this family
for the blood antigen are
which is a recessive trait. The Huntington's disease locus and the locus
and squares represent XY
located on chromosome 4 and are 5 cM apart. Circles represent XX
in the families shown.
individuals. Assume complete penetrance and that no new mutations occur
% %afiected with Huntington’s disease
. .exhibits recessive blood antigen
None of the individuals shown below are both affected with Huntington’s
disease and exhibit the blood antigen.
4+ WY Individual | Genotype
a + 1“ L 1 a+ | a+
=)
a + e 2 +H/+tHR or +H[++
3 " 3 a+/+H
A 2 . a+ | a+
(o)) = a +
i 7 —
P
+ H ° a 1t
e (1 through 4). If there is
a. (4 points) Indicate the genotype of each individual shown in the pedigre
individual. Use + for wild-
more than one possibility, write down all the possible genotypes for a given al shown
each numbered individu
type allele for a given gene. Please write down the genotype next to
antigen. o @ points, escl-
in the pedigree. H: allele for Huntington's disease, a: allele for the blood
g+=Hpe
probability that the indicated grandchild (shown as "?") will develoé3
b. (4 points) What is the
Huntington’s disease? Show your work.
0x Hu O +I
83 1S o +/H9wbpe
Cien
W HD.
1|2 clence ol deelopd)
*Hj 12
e
T
4 {4+ tH
(shown as "?") will both exhibit the
c. (6 points) What is the probability that the indicated grandchild
your work.
recessive blood antigen and develop Huntington’s disease? Show
= |/?_9 = S
Xs FLreg belreen O‘RH)
I’(“H) 2w *x'2 = Hluo = 092>
Y’
