In twin studies, scientists measure _____, which is defined as _____
A. heritability; the extent to which variation in
phenotype in a population is due to variation
in genotype.
B. concordance; the percentage of cases in
which both members of a pair of twins show
the trait when at least one member shows it.
C. concordance; the percentage of cases in
which both members of a pair of identical
twins, but not fraternal twins, show the trait
when at least one member shows it.
D. concordance; the percentage of cases in
which both members of a pair of fraternal
twins, but not identical twins, show the trait
when at least one member shows it.
E. concordance; the extent to which
differences in the environment influences
differences in phenotype.
B
You might also like to view...
Which of the following may result from improper activation of B cells by self antigens?
A. Production of autoantibodies B. Allergic reactions C. Anergy D. Peripheral tolerance E. Production of self-reactive T cells
The AIDS virus becomes established in cells bearing the ________ receptor.
Fill in the blank(s) with the appropriate word(s).
Stomata open when K+ concentration in guard cells ____, followed by water ____ the guard cells by
osmosis.
a. increases, entering b. decreases, entering c. decreases, leaving d. increases, leaving e. increases H+, leaving
Tears and saliva contain ________, an enzyme that kills bacteria
Fill in the blank(s) with correct word