A high level of gene flow into a population increases genetic diversity in a population. A high level of gene flow out of a population decreases genetic diversity in a population. Genetic drift is the change in allele frequencies due to "sampling error" factors. Typically, genetic drift has the biggest impact on small populations.
Gene flow (or gene migration) is a mechanism of evolution (change the allele frequencies) which transfers genetic variation among populations due to migration. High level of gene flow decreases the genetic differentiation between the two populations.
Genetic drift is a mechanism of evolution that acts by chance (“sampling error”) often when a population is reduced in size by a natural disaster (bottleneck effect) or when a small group leaves the main population and forms a colony (founder effect).
Answer: The correct options are C and E.
Explanation: When the rattlesnake population increases, the population of grasshopper and prairie dog are also decreases.
Both grasshopper and prairie dog are herbivores and eaten by rattlesnake. When rattlesnake population increases they feed on grasshopper and prairie dog and decrease occurs in their population.
Answer: 46 chromosomes
Explanation: Germ cells contain a complete set of 46 chromosomes (23 maternal chromosomes and 23 paternal chromosomes). By the end of meiosis, the resulting reproductive cells, or gametes, each have 23 genetically unique chromosomes. The overall process of meiosis produces four daughter cells from one single parent cell.
Answer: A. It is liquid and weighs two pounds.
Explanation:
A provides the most details and includes a quantitative measurement however an actual cup of gasoline does not weigh 2 pounds.