Evolution and Natural Selection

Evolution is the process of

• development of one-celled organisms from mammals

• change in species over long periods of time

• embryonic development of modern humans

• changing energy flow in food webs

Which phrase best defines evolution?

• an adaptation of an organism to its environment

• a sudden replacement of one community by another

• the isolation of organisms to its environment

• a process of change in species over a period of time

When lions prey on a herd of antelope, some of the antelope are eliminated. Which part of the theory of evolution can be used to describe this situation?

• asexual reproduction of the fittest

• isolation of the species

• survival of the best adapted

• new species development due to mutation

What is natural selection?

• individuals that survive are able to breed and pass their traits to offspring. Those that are not successful die and do not pass their traits to offspring

• When humans choose which organisms to breed together in order to produce an offspring with desired traits

• Individuals that survive do not pass their traits to offspring. Instead their offspring will receive a different set of traits

The modern theory of evolution states that a basis for variation within a species is provided by

• mutations and asexual reproduction

• cloning

• sexual reproduction and asexual reproduction

• mutations and sexual reproduction

Which two factors provide the genetic basis for variation within many species?

• asexual reproduction and meiosis

• mutations and sexual reproduction

• competition and the synthesis of proteins

• ecological succession and meiosis

How can the lack of genetic diversity found in populations of endangered species hinder their recovery?

• A lack of genetic diversity prevents the species to be better adapted to different environments

• The species may not be able to reproduce as quickly

The shark has changed very little in the last 50 million years. Which statement best explains why this is the case?

• The shark is well adapted to its relatively unchanged environment

• Sharks have a high reproductive rate and show little change in their genetic makeup from one generation to the next

• sharks need to change only if humans are present in their environment

• sharks have a high mutation and genetic recombination rate

A large population of cockroaches was sprayed with a newly developed, fast acting insecticide. The appearance of some cockroaches that are resistant to this insecticide supports the concept that

• species traits tend to remain constant

• variation exists within a species

• insecticides cause mutations

• the environment does not change

Mutations can only be passed through

• sex cells/gametes

• somatic (body) cells

• sex cells and somatic cells