Problem:
Qiestion 1: In the Ruritanian royal family, in which inbreeding has occurred from time to time over the centuries, there is a history of
males affected by a genetic disease; they seldom live beyond age 30. The present king, Waldemar XII, has the disease; his
wife Queen Marya is unaffected by it, though she is a distant cousin of his. Now they have conceived a son, and the
pregnancy is going fine. Should they worry about the future health of the soon-to-arrive prince?
Argue either a "yes, because..." or a "no, because..." answer (choose one!), based on theory, and stating assumptions.
Question 2: In a given population traits A and B exist, in which each trait has a dominant (A, B) and a recessive (a, b) allele - no codominance or
other unusual things going on. You test-cross a dihybrid individual (genotype AaBb) with an aabb, and see the following numbers and
phenotypes of offspring: (in the table)
How do you explain this pattern? [No need for calculations.]
phenotype: A ,B a ,b A ,b a , B
number: 100 100 10 10
Question 3: Which one of the following options is correct concerning a sex-linked trait?
a. the trait is due to the interaction of several genes, all found on the X chromosome.
b. it must affect the ability of individuals to engage in intercourse
c. its locus must be on the Y chromosome.
d. it may be identified most clearly in the results of reciprocal crosses.
e. it cannot occur in a homozygotic state, only heterozygotic..
Question 4: In a particular habitat, you observe a population whose realized niche is of almost exactly the same extent as its fundamental
niche. Which one of the following options would certainly not apply to such a population?
a. it's probably occupying a habitat in which all species are present at low densities.
b. it's probably occupying a habitat in which abiotic factors are the ones most significant to its survival.
c. it's probably a competitive-dominant species.
d. it's probably occupying a habitat in which stochastic factors are the ones most significant to its survival.
e. it's probably experiencing severe impact from predation and/or disease.
Question 5: You observe a cell of an organism with 2n = 42, when it is at the meiotic stage metaphase II. Which one of the following
would you expect to see in this cell?
a. 21 pairs of tightly-bound chromosomes, distributed across the equatorial plane.
b. a mass of loose, uncoiled chromatin representing 21 pairs of chromosomes.
c. 42 single-stranded chromosomes, distributed across the equatorial plane.
d. 21 single-stranded chromosomes, each undergoing DNA replication.
e. 21 two-stranded chromosomes, distributed across the equatorial plane.
Question 6: In a frequently-disturbed habitat: (choose the incorrect option)
a. there will at times be a considerable biomass of food available.
b. only K-type organisms will be able to survive.
c. there will be an advantage to early maturation and high breeding output.
d. most individual organisms will be small and not very strongly constructed.
e. colonization ability will be a good predictor of organisms' success.
Question 7: A man of blood type (phenotype) AB and a woman of blood type B decide to have children. With only this information,
which one of the following claims about the ABO blood types of their children is correct?
a. none will be type O.
b. all sons will be type B, but daughters will be either AB or B.
c. the majority will be type AB.
d. none can be type A.
e. if there are homozygotes, more than one type of homozygote is possible.
Please suggest the best answer.