Download Monster Genetics Practice Test

MONSTER GENETICS TEST
Scientists sent a remote video rover to a distant planet and detected a population of monster-like
creatures. Records were kept for several mating pairs over several generations. As lead geneticist,
study the records and determine the inheritance pattern for each phenotype in the population.
Figure 1 and Table 1 show the various traits monsters can inherit. Use these as a guide when
answering the questions below.
1.
Figure 2 shows a Punnett square for a pair of mating monsters. What kind of inheritance
pattern best explains the appearance of the mixed spike shapes in the offspring?
a. Codominance
b. Incomplete (intermediate) dominance
c. Sex-linked
d. complete (simple) dominance
2.
In figure 2, what kind of inheritance pattern best explains the gray spots in the offspring?
a. Codominance
b. Incomplete (intermediate dominance)
c. Polygenic
d. Complete (simple) dominance
3.
In figure 2, what kind of inheritance pattern best explains all offspring having kinked tails?
a. Codominance
b. Incomplete (intermediate) dominance
c. Sex-linked
d. complete (simple) dominance
4.
Every time the parents in figure 2 mate, the offspring always have kinked tails. Given this,
What is true about the parents regarding tail shape?
a. One parent is homozygous dominant, while the other is homozygous recessive.
b. One parent is heterozygous while the other is homozygous recessive.
c. Both parents are heterozygous.
d. Both parents are homozygous recessive.
5.
Figure 3 shows a small sample of the variety of tail lengths found among individuals in the
population. What kind of inheritance pattern best explains this wide variation in tail length?
a. Codominance
b. Incomplete (intermediate) dominance
c. Polygenic
d. Complete (simple) dominance
6.
Figure 4 shows a fangless monster (missing the long teeth). Scientists observed that about 8%
of males have this trait while only 0.5% of females do. What kind of inheritance pattern best
explains this rare trait?
a. Codominance
b. Sex-linked
c. Multiple alleles
d. Complete (simple) dominance
7.
One study (figure 5) found that white spots are always associated with crossed eyes. Both
conditions are known to be recessive traits. What is the best explanation for this pattern?
a. The genes for spot color and eye position are easily segregated by crossing-over events.
b. The genes for spot color and eye position are found on separate chromosomes.
c. The spot color and eye-position genes are on the same chromosome.
d. The inheritance pattern occurs only during mitosis, not meiosis.
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MONSTER GENETICS TEST
8.
One day, a monster was born with a never-seen-before curly tail (see figure 6). What is the
best explanation for this novel (brand new) phenotype?
a. Both parents were homozygous dominant for the new phenotype. The curly-tailed
baby was then born homozygous recessive.
b. The mutation that changed the tail shape occurred in the baby after it was born.
c. A mutation in the DNA of one parent’s tail cell created the new look.
d. Prior to meiosis, a kinky-tail allele mutated to produce the new curly-tail phenotype,
which was then involved in the fertilization event that produced the curly-tailed baby.
9.
The curly tail in figure 6 is now a third tail shape available to the monster population. This
type of inheritance pattern where genes occur in more than two forms is called
a. Multiple alleles
b. Incomplete (intermediate) dominance
c. Sex-linked
d. Codominance
10. During the colder months on the planet, babies are born with tails that are darker than those
born in warmer months. Just like animals on Earth, this demonstrates that
a. darker tails are superior to lighter tails.
b. lighter tails are superior to darker tails.
c. some characteristics can be influenced by the environment.
d. baby monsters should not be born in cold weather.
11. If the cross-over event shown in figure 7 were to occur in the chromosomes of monsters, what
effect would that have on the variability of the population?
a. The number of different-looking individuals in the population would decrease to the point
where all monsters would eventually look alike.
b. It would have no effect what-so-ever.
c. The cross-over event would make all monsters sterile, thus no babies could be born.
d. It would greatly increase the variability of phenotypes in the population, since alleles
could be shuffled into new combinations.
12. Shown below is the cell of a monster in the G2 stage of interphase (the DNA has already
replicated). Study the diagram and determine the diploid number (2N) of a monster?
a. 2N = 3
b. 2N = 6
c. 2N = 12
d. 2N = 24
White chromosomes
are female sourced.
Cell
Nucleus
Black chromosomes
are male sourced.
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MONSTER GENETICS TEST
13. A sample of a monster’s germ cell was obtained and observed as it underwent meiosis.
Study the diagram of the meiotic event below and determine what stage of meiosis it is in.
a. metaphase I
b. telophase II
c. anaphase I
d. metaphase II
White chromosomes
are female sourced.
Black chromosomes
are male sourced.
Spindle fibers
14. After watching several monster germ cells complete meiosis, scientists determined that only
eight unique types of gametes could form. Study the eight gametes types below and determine
what conclusion(s) could be drawn from the process of monster meiosis.
a. There is evidence that monster chromosomes always cross-over and exchange DNA.
b. Mendel’s law of independent assortment does not apply to monster meiosis.
c. There is no evidence of crossing-over but independent assortment does occur.
d. Both crossing-over and independent assortment never occurs.
15. One day a mating pair of monsters bit into a rock that was shaped like their favorite
food. Unfortunately, the long-teeth (fangs) of both monsters broke completely off at the gums
and never grew back. Given what you know about inheritance, what will their future offspring
look like?
a. Because the parents are now fangless, all of their offspring will be fangless too.
b. The offspring will have fangs, since both parents still carry the genes for them.
c. The offspring will grow fangs, then lose them at the same age that their parents did.
d. The offspring will grow broken fangs up to the gum level.
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MONSTER GENETICS TEST
Figure 1: Monster Phenotypes
Males have chest hair and an arrow tipped tail
Females have a bow on their tail
Straight eyes
Fangs
Crossed eyes
Pointed spikes
Fangless
Arrow tip
(males)
Chest hair
(males)
Bow
(females)
Kinky
tail
Black spots
Straight
tail
White spots
Mixed spikes
Gray
spots
Table 1: Monster Phenotypes
Gene
Characteristic
Allele Traits
Pointed
Rounded
Black
White
Gray
Kinked
Straight
Fanged
Fangless (no fangs)
Straight-eyed
Crossed-eyed
Varies
Spikes on back
Spot color
Tail shape
Canine-like long
teeth
Eye position
Tail length
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Rounded spikes
MONSTER GENETICS TEST
Figure 2: A typical monster cross
Figure 4: A fangless male
X
Figure 5: Crossed-eyes always
appear with white spots
All offspring above have gray spots, mixed
spikes, kinked tails, and straight eyes.
Figure 6: A female with a
never-before-seen curly tail
Figure 3: Variation in Tail Length
Figure 7: Chromosomes crossingover and exchanging DNA
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MONSTER GENETICS TEST
Answers
1.
A
2.
B
3.
D
4.
A
5.
C
6.
B
7.
C
8.
D
9.
A
10.
C
11.
D
12.
B
13.
A
14.
C
15.
B
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