a Flashcards
A gene in Hardy-Weinberg equilibrium has only two alleles. The frequency of one homozygote is 0.16, or 16%. What will be the frequency of heterozygotes?
.48
Which process is the result of sampling error in finite populations?
genetic drift
Which of these is not a prezygotic isolating mechanism?
hybrid sterility
Pleiotropy occurs when:
one gene simultaneously affects multiple traits
Mutations arise stochastically. This means that:
the chance a mutation occurs is not affected by whether it is advantageous or not
Which of the following is not a necessary condition for natural selection to occur?
assortative mating
Which statement is true?
natural selection cannot follow a predetermined path
Protists form a paraphyletic group.
TRUE
In giraffes, the recurrent laryngeal nerve makes a needless detour of about 15 feet.
True
Intrasexual selection in nature most commonly occurs as:
male-male competition
Pathogenic (disease-causing) bacteria found in many hospitals are quite resistant to antibiotics. This is best described as an example of:
directional selection
Reversals to the usual forms of sexual selection are expected when:
male investment in offspring is high
What is the name of the mating system in which successful females typically mate with multiple males during a breeding season, but a male typically mates with one female?
polyandry
Two individuals are homozygous for different alleles at two genes (AABB vs. aabb). How many different genotypes are possible among their F2 progeny?
9
Which type of macromutation is especially important in the evolution of gene families?
duplications
This figure illustrates:
vestigial character
Which process is the ultimate source of genetic variation?
mutation
Which of these conditions should completely prevent the occurrence of evolution by natural selection?
all phenotypic variation among individuals is caused by environmental factors
Frogs are more closely related to fish than they are to humans.
false
Which phenomenon causes significant divergence between the genetic make-up of an individual’s gametes and the genetic make-up of the gametes that produced the individual in the first place?
recombination
The figure above indicates:
auto polyploidy
When we reconstruct phylogenies using morphological traits, we need to rely on characters that are both unique and derived.
false
What is the type of allopatric speciation in which gene-flow barriers arise without dispersal?
vicariant speciation
Which of the necessary conditions for natural selection is not illustrated in this figure?
underlying genetic variation
