Stable expression of harmful recessive traits across generations most likely occurs in populations with a high level of:
A. emigration
B. natural selection
C. inbreeding
D. random mating
Click for Explanation
Stable expression of traits, even harmful recessive traits, most likely occurs in populations which satisfy the Hardy-Weinberg equilibrium conditions: 1) large population, 2) mutational equilibrium, 3) no immigration or emigration, 4) random mating, and 5) no selection for the fittest organism. The only answer choice satisfying one of these conditions is answer choice d) random mating.
A. emigration, incorrect, Emigration from a population will artificially alter the gene pool frequencies.
B. natural selection, incorrect, Selection for fittest organisms introduces bias towards certain genes in the pool, again taking away the random criterion for the statistical gene stability defined by Hardy-Weinberg.
C. inbreeding, incorrect, Inbreeding tends to increase the frequency of harmful recessive traits because it artificially creates a smaller subpopulation within the larger gene pool. These smaller populations also frequently share deleterious genes between relatives, thereby amplifying recessive gene expression. Inbreeding contradicts the large population and the random mating criteria of Hardy-Weinberg.
D. random mating, correct.
Want more MCAT practice?
We’ve got options for every schedule and learning style!
From the best online MCAT course created by top instructors with 524+ MCAT scores to the most representative full-length practice exams and private tutoring, we can custom tailor your MCAT prep to your goals!
Not sure which option is right for you? Schedule a free MCAT consultation with an MCAT expert using the form below. No obligation, just expert advice.
Related Posts
Search the Blog
Free Consultation
Interested in our Online MCAT Course, One-on-One MCAT Tutoring or Med admissions packages? Set up a free consultation with one of our experienced Senior Student Advisors.
Schedule NowPopular Posts
-
-
MCAT Blog What's on the MCAT? -
-
-
MCAT Blog How to Review MCAT Full Lengths
Free MCAT Practice Account
Need great MCAT practice?Get the most representative MCAT practice possible when you sign up for our free MCAT Account, which includes a half-length diagnostic exam and one of our full-length MCAT practice exams.
Learn More