GENETICS EXAM 2 PRACTICE QUESTIONS
AND DETAILED SOLUTIONS
◉ A chromosome has the following segments, where • represents
the centromere:
ABCDE•FG
What types of chromosome mutations are required to change this
chromosome into each of the following chromosomes? (In some
cases, more than one chromosome mutation may be required.)
d. A F • E D C B G.
Answer: PERICENTRIC INVERSION, as the gene order and
centromere position have changed
◉ A chromosome has the following segments, where • represents
the centromere:
ABCDE•FG
What types of chromosome mutations are required to change this
chromosome into each of the following chromosomes? (In some
cases, more than one chromosome mutation may be required.)
,e. A B C D E E D C • F G.
Answer: duplication and paracentric inversion
◉ Species I is diploid (2 n = 4) with chromosomes AABB; related
species II is diploid (2 n = 6) with chromosomes MMNNOO. Give the
chromosomes that would be found in individuals with the following
chromosome mutations:
a. Autotriploidy in species I..
Answer: AAABBB
gives an extra set of chromosomes
6 chromosomes
◉ Species I is diploid (2 n = 4) with chromosomes AABB; related
species II is diploid (2 n = 6) with chromosomes MMNNOO. Give the
chromosomes that would be found in individuals with the following
chromosome mutations:
b. Allotetraploidy including species I and II..
Answer: allotetraploidy of species I and II = for (species I, n=2, and
for species II, n=3. cross b/w them then 2n = 5 so allotertaploidy of
sp I and II is = 4n = 10 chromosome.
,◉ Species I is diploid (2 n = 4) with chromosomes AABB; related
species II is diploid (2 n = 6) with chromosomes MMNNOO. Give the
chromosomes that would be found in individuals with the following
chromosome mutations:
c. Monosomy in species I..
Answer: AAB or ABB
2n-1
3 chromosomes
◉ Species I is diploid (2 n = 4) with chromosomes AABB; related
species II is diploid (2 n = 6) with chromosomes MMNNOO. Give the
chromosomes that would be found in individuals with the following
chromosome mutations:
d. Trisomy in species II for chromosome M..
Answer: MMMNNOO or MMNNNOO or MMNNOOO
2n+1
7 chromosomes
, ◉ Species I is diploid (2 n = 4) with chromosomes AABB; related
species II is diploid (2 n = 6) with chromosomes MMNNOO. Give the
chromosomes that would be found in individuals with the following
chromosome mutations:
e. Tetrasomy in species I for chromosome A..
Answer: AAAABB or AABBBB
2n+2
6 chromosomes
◉ Species I is diploid (2 n = 4) with chromosomes AABB; related
species II is diploid (2 n = 6) with chromosomes MMNNOO. Give the
chromosomes that would be found in individuals with the following
chromosome mutations:
f. Allotriploidy including species I and II..
Answer: Allotriploid formed from species I and II
There will be n from sp I and 2n from species II
AND DETAILED SOLUTIONS
◉ A chromosome has the following segments, where • represents
the centromere:
ABCDE•FG
What types of chromosome mutations are required to change this
chromosome into each of the following chromosomes? (In some
cases, more than one chromosome mutation may be required.)
d. A F • E D C B G.
Answer: PERICENTRIC INVERSION, as the gene order and
centromere position have changed
◉ A chromosome has the following segments, where • represents
the centromere:
ABCDE•FG
What types of chromosome mutations are required to change this
chromosome into each of the following chromosomes? (In some
cases, more than one chromosome mutation may be required.)
,e. A B C D E E D C • F G.
Answer: duplication and paracentric inversion
◉ Species I is diploid (2 n = 4) with chromosomes AABB; related
species II is diploid (2 n = 6) with chromosomes MMNNOO. Give the
chromosomes that would be found in individuals with the following
chromosome mutations:
a. Autotriploidy in species I..
Answer: AAABBB
gives an extra set of chromosomes
6 chromosomes
◉ Species I is diploid (2 n = 4) with chromosomes AABB; related
species II is diploid (2 n = 6) with chromosomes MMNNOO. Give the
chromosomes that would be found in individuals with the following
chromosome mutations:
b. Allotetraploidy including species I and II..
Answer: allotetraploidy of species I and II = for (species I, n=2, and
for species II, n=3. cross b/w them then 2n = 5 so allotertaploidy of
sp I and II is = 4n = 10 chromosome.
,◉ Species I is diploid (2 n = 4) with chromosomes AABB; related
species II is diploid (2 n = 6) with chromosomes MMNNOO. Give the
chromosomes that would be found in individuals with the following
chromosome mutations:
c. Monosomy in species I..
Answer: AAB or ABB
2n-1
3 chromosomes
◉ Species I is diploid (2 n = 4) with chromosomes AABB; related
species II is diploid (2 n = 6) with chromosomes MMNNOO. Give the
chromosomes that would be found in individuals with the following
chromosome mutations:
d. Trisomy in species II for chromosome M..
Answer: MMMNNOO or MMNNNOO or MMNNOOO
2n+1
7 chromosomes
, ◉ Species I is diploid (2 n = 4) with chromosomes AABB; related
species II is diploid (2 n = 6) with chromosomes MMNNOO. Give the
chromosomes that would be found in individuals with the following
chromosome mutations:
e. Tetrasomy in species I for chromosome A..
Answer: AAAABB or AABBBB
2n+2
6 chromosomes
◉ Species I is diploid (2 n = 4) with chromosomes AABB; related
species II is diploid (2 n = 6) with chromosomes MMNNOO. Give the
chromosomes that would be found in individuals with the following
chromosome mutations:
f. Allotriploidy including species I and II..
Answer: Allotriploid formed from species I and II
There will be n from sp I and 2n from species II
