Genes and Variation
The genes carried by all members of a particular population make up the population’s
What is gene pool?
When individuals with an average form of a trait have the highest fitness, the result is
What is stabilizing selection?
A factor that is necessary for the formation of a new species is
What is reproductive isolation?
Hox genes control
What is embryological development?
Natural selection acts directly on
What are phenotypes?
If the allele frequency of a population changes, it tells us that the population is.
What is evolving?
Genetic drift tends to occur in populations that
What is very small?
The separation of populations by barriers such as rivers, mountains, or bodies of water is called
What is geographic isolation?
A farmer sprays insecticide on his crops to kill unwanted insects. Most of the insects die, and the chemicals have the effect of damaging the DNA of the insects that are not killed. Allele frequencies change because of
What is mutation?
A change in the genetic material of a cell is called a
What is a mutation?
Sexual reproduction among members of a population results in this type of change in allele frequency
What is no change?
The type of genetic drift that follows the colonization of a new habitat by a small group of individuals is called
What is the founder effect?
In order to be considered a species, organisms must give rise to
What is reproduce fertile offspring?
In a population of mice if no natural selection takes place this population is said to be in this
What is genetic equilibrium?
In organisms that reproduce sexually, most variation that can be inherited is due to
What is gene recombination?
Genetic recombination includes the independent movement of chromosomes during meiosis as well as
What is crossing over?
One similarity between natural selection and genetic drift is that both events
What is involve a change in a population’s allele frequencies?
A population having some plants whose flowers open at midday and other plants whose flowers open late in the day may experience
What is temporal isolation?
One day, 10 individuals with the genotype aa leave the area and cross a river into a new habitat. The allele frequency has changed because of
What is emigration?
The number of phenotypes produced for a given trait depends upon
What are the number of genes that control the trait?
In genetic drift, the allele frequencies in a gene pool change because of
What is chance?
These scientists described the conditions required to maintain genetic equilibrium
What is the Hardy Weinberg principle?
The geographic isolation of two populations of a species tends to increase differences between their gene pools because it
What is prevents interbreeding?
This can produce a duplication in a gene
What is crossing over in meiosis?
Three sources of genetic variation are
What are sexual reproduction, lateral gene transfer and mutations?