Why is it that mutation, acting alone, has little effect on allele frequency, and therefore evolution? What other factors will magnify the effect?
What will be an ideal response?
If the mutation rate for a gene is known, we can use the Hardy–Weinberg formula to calculate the new allele frequency resulting from mutations in that gene. Let's use the dominant trait achondroplasia as an example. For this calculation, we assume that initially only homozygous recessive individuals with the genotype dd (normal stature) were present in the population. We will also assume that mutation has added new mutant (D) alleles to each generation at the rate of 1X10-5 . To change the frequency of the recessive allele (d) from 1.0 (100%) to 0.5 (50%) at this rate of mutation will require 70,000 generations, or 1.4 million years. Our conclusion in this case is that mutation alone has a minimal impact on the amount of genetic variation present in a population. In other words, mutation generates all new alleles, but except for very small populations, drift, migration, and selection are the forces that change the frequency of alleles in a population.
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If the figure above shows the dances of bees in a hive at twelve noon on March 21 in the northern hemisphere, which dance is communicating that the food is to the south of the hive?
A) dance A B) dance B C) dance C D) It is not possible to tell if any of the dances indicate the food is to the south of the hive.
You are excited because your lab is studying the first microorganisms retrieved from Mars! Interestingly, their genetic material consists of a single-stranded nucleic acid with six different nitrogenous bases. Like organisms from Earth, segments of the nucleic acid contain the code for making proteins. If the genetic code in these organisms was read in groups of 2 bases instead of 3, what is the maximum number of amino acids that could be coded for assuming that only one codon functioned as a stop codon? (Enter your answer as a numeral, not a word; e.g., enter 17, not seventeen.)
Fill in the blank(s) with the appropriate word(s).
Most ATP is generated during the process of glycolysis.
a. true b. false
Which of the following is a member of the domain bacteria?
a. euglena b. methanogens c. halophiles d. cyanobacteria e. giardia