USABO Open Exam
The production of the genetically engineered "golden rice" could be important to people
of developing nations, especially in South-East Asia, because:
A. people are more likely to consume yellow grains than white.
B. golden rice is less expensive to grow and harvest than white rice.
C. golden rice has been engineered to be resistant to most commercially available
herbicides.
D. golden rice has been engineered to contain higher concentrations of β-carotene than
white rice.
E. golden rice has been engineered to produce biodegradable plastics. - ANS-D. golden
rice has been engineered to contain higher concentrations of β-carotene than white rice.
A large population of laboratory rats was allowed to breed randomly for a number of
generations. In this population, agouti fur is encoded by the A allele and is dominant to
the black fur trait encoded by the a allele. At the beginning of the breeding cycles, 49%
of the rats had black fur. At the end of the breeding cycles, this percentage was the
same. The rest of the animals had agouti fur. The heterozygotes with agouti fur were
indistinguishable from homozygotes with agouti fur. What percentage of this population
is probably heterozygous for the fur color trait assuming the rats are following
Hardy-Weinberg population genetics?
A. 7%
B. 30%
C. 42%
D. 49%
E. 70% - ANS-C. 42%
An individual suffers brain damage that results in respiratory failure. Which region of the
brain was most likely damaged?
A. Substantia nigra
B. Pons
C. Red nucleus
D. Superior colliculus
E. Reticular formation - ANS-B. Pons
, To keep their dog breeds "pure," breeders will keep dogs of different breeds in
physically separate areas when the female is in heat. This aspect of artificial selection is
most closely analogous to which of the following reproductive isolating mechanisms?
A. Mechanical isolation
B. Gametic isolation
C. Cooperative breeding
D. Ecological isolation
E. Hybrid breakdown - ANS-D. Ecological isolation
A man and a woman get married and soon learn that they both have a rare, genetically
inherited recessive disorder that makes them prone to dizziness. Worried about the fate
of their children, they seek the advice of a genetic counselor. She sequences their
genomes and assures them that none of their children will have the disorder. What
information would she have to obtain from the sequencing procedure that allows her to
make this claim?
A. The dizziness phenotype in the man is due to a mutation in a gene other than the
gene responsible for the woman's phenotype.
B. The dizziness disorder is an autosomal recessive trait.
C. The man and the woman are related genetically causing the same dizziness
phenotype.
D. The dizziness disorder is linked to the sex chromosomes.
E. It is impossible for the man and the woman to have unaffected children - the genetic
counselor is wrong. - ANS-A. The dizziness phenotype in the man is due to a mutation
in a gene other than the gene responsible for the woman's phenotype.
An animal experiences an acid-base imbalance in the arterial blood that results in
acidosis. To increase pH toward normal, which direction would the ventilation rate be
changed and what would be the corresponding change in arterial PCO2?
A. Ventilation rate increases, arterial PCO2 increases
B. Ventilation rate increases, arterial PCO2 decreases
C. Ventilation rate decreases, arterial PCO2 increases
D. Ventilation rate decreases, arterial PCO2 decreases
E. None of the above - ANS-B. Ventilation rate increases, arterial PCO2 decreases
Plants, animals and a quantity of air were sealed into a large glass bottle to comprise a
balanced aquarium. After three months, the plants and animals in the aquarium appear
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller Hkane. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $7.99. You're not tied to anything after your purchase.
