Natural Selection

________ is a mechanism by which individuals that have inherited beneficial adaptations produce more offspring on average than do other individuals.

'Blueprint' or code for an organisms' way of life, made of nucleic acids.

• DNA

• natural selection

• population

• mutation

A group of organisms so similar that they can reproduce and have fertile offspring.

• DNA

• Natural Selection

• Population

• Mutation

Characteristics are passed from one generation to the next through DNA.

• Inheritance

• Mutation

• Allele

• Natural selection

A change in the DNA sequence.

• Natural selection

• Allele

• Mutation

• Population

Any of the alternative forms of a gene.

• DNA

• Population

• Allele

• Natural Selection

A heatwave hits the arctic, and a group of polar bears struggles to stay cool with all their thick fur. What is likely to happen?

• The polar bears will individually adapt by making less fur in the heat, so that they don’t overheat.

• The polar bears with less fur will survive, and those with a lot of fur will die.

• The polar bears will migrate to a new area that is colder.

A population of grasshoppers in the Kansas prairie has two color phenotypes, green and brown. Typically, the prairie receives adequate water to maintain healthy, green grass. Assume a bird that eats grasshoppers moves into the prairie. How will this affect natural selection of the grasshoppers?

• The green phenotype should be more easily seen by the predator and decrease in frequency.

• The brown phenotype should be more easily seen by the predator and decrease in frequency.

• Both green and brown grasshoppers should be eaten and their relative numbers should remain constant.

• Predation will cause the brown grasshoppers to mutate into green grasshoppers.

If the weather in Richmond, Virginia, changed to very cold (snow on the ground 8 months of each year) over the next few years, what change might occur?

• The cold weather would cause a mutation in squirrels which causes their fur to be white.

• If a mutation occurred which caused white fur to develop, such white squirrels would have a better chance to survive and produce more offspring with the characteristic.

• Evolution would definitely occur resulting in white squirrels

• Natural selection would cause a new genotype to appear in the population, resulting in squirrels with white fur.

• Natural selection would not permit such climatic changes.

Which of the following is NOT an example of natural selection?

• Plants with thorns are less likely to be eaten by herbivores than other members of the same species that lack thorns.

• Bacterial populations in hospitals develop resistance to drugs used to combat infection by them.

• Scientists breed cows that give greater amounts of milk than their ancestors.

• Fruit fly larvae with an enzyme to break down alcohol are better able to feed on fermenting fruit than those that lack the enzyme.

• Female fish that produce more eggs leave more offspring than those that produce fewer eggs.