Unit 8 and 9

A population of bacteria is treated with hand sanitizer. Because of genetic variation in the population, what is a possible outcome?

• The population will grow quickly.

• All of the bacteria are already resistant.

• They will get better at obtaining a food source.

• Some may be resistant and survive

One of the biggest ways that a species evolves is because some organisms with some traits survive and reproduce better than others. This process is known as

• natural selection.

• convergent evolution.

• coevolution.

• sexual selection.

Genes for traits that help an organism be more successful reproductively can be expected to

• cause it to evolve into a new species

• become more common in the future

• cause the extinction of the species

• eventually be eliminated by natural selection

An adaptation is

• any trait an organism possesses

• how an organism evolves during its own lifetime

• a gene an organism has

• a trait that helps an organism survive in its environment

Genetic diversity is ULTIMATELY/MAINLY the result of

• meiosis

• viruses

• mutations

• reproduction

Which of the following does NOT an example of evolution

• Horses becoming taller and faster over millions of years

• All species of tortoises in the Galapagos islands descending from a common ancestor.

• Human brains becoming larger over time

• A caterpillar going through a change into a butterfly

Which of the following does NOT increase genetic variation?

• Mutations

• Gene flow

• Mitosis

• Crossing over

Which of the following is NOT a principle of natural selection?

• Most species produce more offspring than will actually reproduce

• Organisms complete for limited resources

• Evolution will occur as an organism gets older and learns more

• In every population, adaptations allow some organisms to survive and reproduce better than others

Individuals that are well adapted to their environment will survive and produce _____________.

• fewer mutations

• more offspring

• stronger gene

• better traits

During a period of droughts in the Mojave Desert, seeds that are small and easily eaten become more and more rare, leaving mostly seeds that are large with hard-cased shells behind. The only birds that can

• small birds will gain larger beaks by exercising their mouths more.

• More small-beaked birds will die than larger-beaked birds. The offspring produced in the following generations will have a higher percentage of birds with larger beaks.

• Smaller birds will mutate their beak genes, resulting in the following generations having a higher percentage of birds with larger beaks.

• Small birds will eat more to gain weight in preparation for the drought. As a result, they will grow larger beaks from eating more.