bio chapters 13 n 15 review

What is responsible for genetic variation in bacteria?

- Mutations occur in the genome during binary fission. - Gene transfer from a different bacterial strain occurs. - Mutations produce new alleles, therefore new traits.

Which of these is a human-caused environmental change that animals face?

- climate change - urbanization - urban dwelling

S. aureus can be transferred from person to person by _____.

- direct contact with contaminated skin - the use of soap and towels - contaminated surfaces

populations of asexually reproducing bacteria acquire genetic variation by

- gene transfer - mutation

the bottleneck effect is an example of

- nonadaptive evolution - genetic drift

Treating and preventing infections by antibiotic-resistant bacteria can be accomplished by _____.

- reducing antibiotics in livestock feed - washing hands frequently - disinfecting common surfaces - researching new vaccines

Evolutionary fitness describes

- successful in the environment they live in - reproduces successfully

MRSA and drug-resistant staph refer to _____.

-staph strains that are resistant to penicillins -staph strains that are resistant to cephalosporins -staph strains that are resistant to beta-lactams

MRSA sickens some 75,000 people in the United States each year and kills almost _____.

10,000

Experts estimate that approximately _____ of the U.S. population (nearly 90 million people) is colonized by S. aureus.

30%−40%

Phylogenic Tree of Life

A branching diagram of relationships showing common ancestry.

Population

A group of individuals that belong to the same species and live in the same area

vestigal structures

A structure inherited from an ancestor that no longer serves a clear function in the organism that possesses it.

Extinction

A term that typically describes a species that no longer has any known living individuals.

plate tectonics

A theory stating that the earth's surface is broken into plates that move.

Adaptation

A trait that helps an organism survive and reproduce

fossil record

An assemblage of fossils arranged in order of age, providing evidence of changes in species over time.

adaptive radiation

An evolutionary pattern in which many species evolve from a single ancestral species

raioactive isotopes

An unstable form of an element that decays into another element by radiation, that is, by emitting energetic particles.

Which step is NOT involved in bacterial reproduction?

Daughter cells stay attached.

relative dating

Determining the age of a fossil from its position relative to layers of rock or fossils of known age.

taxonomic ranks

Domain, Kingdom, Phylum, Class, Order, Family, Genus, and Species

convergent evolution

Evolution toward similar characteristics in unrelated species

Phylogeny

Evolutionary history of a species

gene transfer

Movement of genetic information between organisms

allele frequency

Number of times that an allele occurs in a gene pool compared with the number of alleles in that pool for the same gene

punctuated equilibrium

Periodic bursts of species change as a result of sudden environmental change.

sedimentary rock

Rock formed from the compression of layers of particles eroded from other rocks.

igneous rock

Rock formed from the cooling and hardening of molten lava.

homologous structures

Structures in different species that are similar because of common ancestry.

Domains

The highest (most inclusive) category in the modern system of classification. There are three domains: Bacteria, Archaea, and Eukarya.

continental drift

The hypothesis that states that the continents once formed a single landmass, broke up, and drifted to their present locations

fossils

The preserved remains or impressions of once-living organisms.

Taxonomy

The scientific study of how living things are classified

An antibiotic-resistant allele confers a fitness cost. What would you predict about the growth of the bacteria with the resistant allele compared to the growth of bacteria without the sensitive allele in the presence or absence of antibiotics?

The sensitive strain will have the highest fitness in the absence of antibiotic, and the resistant strain will have the highest fitness in the presence of antibiotic.

Biogeography

The study of the distribution of organisms in geographical space.

half-life

The time it takes for one-half of a sample of a radioactive isotope to decay.

radiometric dating

The use of radioactive isotopes as a measure for determining the age of a rock or fossil.

divergent evolution

This happens when one species evolves into separate species.

directional selection

When the environment favors an extreme phenotype, causing the population to shift in one direction over time

Evolution is defined as

a change in the frequency of alleles in the POPULATION over time.

MRSA is caused by _____.

a drug-resistant form of Staphylococcus aureus

evolution is

always occurring to some degree in any population

Invertebrates are

animals without a backbone

Chemicals that either kill bacteria or slow their growth by interfering with the function of the essential bacterial cell structures are _____.

antibiotics

Antibiotics _____.

are chemicals that interfere with the functioning of essential bacterial cell structures

A type of asexual reproduction in which one parent cell divides into two is called _____.

binary fission

The study of how organisms are distributed in geographic space is called _____.

biogeography

How does geographic isolation contribute to speciation?

by making it more difficult for members of the species to locate each other.

taking antibiotics when youre sick causes _______ selection within the population of bacteria

directional

The type of natural selection in which organisms with phenotypes at one end of the spectrum are favored by the environment is _____.

directional selection

mass extinction

event in which many types of living things become extinct at the same time

adaptive evolution

evolution that results in a better match between organisms and their environment

stabalizing selection

favors average version of the trait

The relative ability of an organism to survive and reproduce in a particular environment is known as _____.

fitness

An organism's ability to survive and reproduce in a particular environment is called its

fitness.

what species would be most closely related

genus

Where is MRSA most likely to be a problem?

in the bloodstream

All of these statements are true about natural selection EXCEPT _____.

it works best in genetically uniform populations

What are the two major mechanisms by which bacterial populations generate genetic diversity?

mutation and meiosis

Differential survival and reproduction of individuals in response to environmental pressure that leads to changes in allele frequencies in a population over time is called _____.

natural selection

The most severe disease that can result from MRSA is _____.

necrotizing fasciitis

Which hypothetical antibiotic would treat bacterial infections by interfering with bacterial reproduction?

one that decreases cell membrane synthesis

Fitness is determined by the interaction between _____ and the environment.

phenotype

Staphlococcus aureus is a spherical bacterium that can cause:

pimples, boils, and wound infections.

A group of organisms of the same species living together in the same geographic area is called a(n) _____.

population

Natural selection acts on

populations

As far as how many species there are on the planet Earth (i.e., species diversity), which of the following groups may be immeasurable?

protists, bacteria, and archaea

Homology

similarity resulting from common ancestry

On which part of your body is normal staph most likely to reside?

skin

Which of the four regions of the body contain species of staph that are considered helpful?

skin

A type of natural selection in which organisms near the middle of the phenotypic range of variation are favored is _____.

stabalizing selection

In humans, very large birth weight babies and very tiny babies do not survive as well as midrange babies. What kind of selection is acting on human birth weight?

stabilizing selection

The below graph shows _____ selection. If it showed a change from medium birth weight babies being the majority to only low birth weight babies being the majority, this would be _____ selection.

stabilizing; directional

natural selection

the process by which the indviduals best adapted to their environment, survive & pass their traits on to their offspring

Which of these is decreased when there is stabilizing selection?

the range of phenotypic variation

A bottleneck is best described as a reduction in the size of an original population followed by an expansion in size as the surviving members reproduce.

true

An organism's fitness depends on its environment.

true

MRSA is composed of a number of unique strains of staph bacteria.

true

Mating that occurs between closely related individuals is known as inbreeding.

true

Tetrapods

vertebrate animals having four feet, legs or leglike appendages

diversifying selection

when the environment favors the ends of a phenotypic spectrum

Your physician had prescribed a β-lactam antibiotic for your sister. Your sister took biology in high school and is refusing to take the antibiotic because she says that it will affect osmosis in her cells. Which reason can you use to help your sister understand how the antibiotic will work?

β-lactam affects bacterial cell walls, and it can't affect human cells because they do not have cell walls.