Week 12 Quiz

___________ occurs when a mutation causes a change in the H and N spikes on the influenza virus. ___________ occurs when two different influenza viruses infect the same host cell, and a new form of the virus is manufactured.

Antigenic drift; Antigenic shift

The following are considered to be evidence of natural selection that Darwin observed aboard the Beagle EXCEPT:

Collecting fossilized remains of extinct animals along the west coast of South America, Darwin believed that all species were created at the same time and did not change form.

Which mode of natural selection is being described below? Changes in the environment direct natural selection to favor the variation at one end of the distribution.

Directional selection

Natural selection causes mutations.

False

Components of natural selection

In a population, individuals vary in their heritable traits. In a population, individuals struggle to exist. In a population, individuals differ in their fitness. Over multiple generations, populations become adapted to their environment.

Fitness, in reference to the theory of evolution by natural selection, describes reproductive success.

True

Circumstance necessary for evolution to occur

Variation for a particular trait exists within a population. A particular trait must be able to be passed on to the next generation.

Lines of evidence for evolution

a. Line of evidence 1, anatomical evidence , is the comparison of physical structures between species. b. Line of evidence 2, genetic material , is the comparison of genetic and biochemical similarities to indicate evolutionary relationships. c. Line of evidence 3, the fossil record , is a line of evidence that provides information on transitional species. d. Line of evidence 4, embryonic evidence , focuses on embryo comparisons because some features may be present in the embryo that are not apparent in the adult form.

Comparing lines of evidence for evolution

a. Transitional fossils not only capture the "in-between" forms on the path to present-day species, but they can also provide an indication of the timeline of the changes that took place. True b. Shared physical features due to a common ancestor are said to be homologous structures. True c. Analogous structures evolved independently in different organisms because the organisms lived in similar environments or experienced similar selective pressures. True d. Analogous structure are physical features that look alike and are marks of common ancestry. False

The differences between heritable traits of organisms of a population, also known as _____________, is the primary force driving the mechanism of ________________.

genetic variation; natural selection

The change in the heritable traits of a population continues because natural selection ____________ the frequency of the advantageous trait in the population and _____________ the frequency of detrimental traits.

increases; decreases

The avian influenza virus typically infects and transmits the virus among ________ animal species at a time.

one

Evolution is described as the change in heritable traits of a(n) __________ over a period of time.

population