BIOLOGY 1407 EXAM 1 QUESTIONS
REVIEW
Multicellular organisms evolved from three different ancestral lineages: stramenopiles,
unikonts, and archaeplastids. Of these, fungi and animals evolved from two different
lineages of ________, and land plants are ________. - Correct Answers -unikonts;
archaeplastids
Chemoautotrophic bacteria obtain their carbon from ________ and their energy from
________. - Correct Answers -CO2; reactions involving inorganic chemicals
Dunaliella salina is a bacterium that is able to live in aqueous solutions with such high
salt concentrations that the salt cannot fully dissolve. D. salina is an example of a(n) -
Correct Answers -extreme halophile.
________ are toxic proteins secreted by pathogenic bacteria, and ________ are toxic
components of the outer membrane of gram-negative bacteria. - Correct Answers -
Exotoxins; endotoxins
Which of the following is a member of the domain Archaea? - Correct Answers -
methanogens
One difference between gram-positive and gram-negative bacteria is that - Correct
Answers -gram-positive bacteria have more peptidoglycan in their cell walls.
The heterokaryotic phase of a fungal life cycle is a - Correct Answers -stage in which
hyphae contain two genetically different haploid nuclei.
Humans are an example of - Correct Answers -chemoheterotrophs
Heterotrophic eukaryotes that digest their food externally and absorb the small
molecules are referred to as - Correct Answers -fungi.
Threadlike fungal filaments are called - Correct Answers -hyphae.
The ultimate source of all new alleles is - Correct Answers -mutation.
Structures that evolved from the same structure in a common ancestor are - Correct
Answers -homologous
, The process through which species not closely related may come to resemble one
another if they live in a similar environment is known as - Correct Answers -convergent
evolution.
Uplift and formation of a mountain range divide a freshwater snail species into two
isolated populations. Erosion eventually lowers the mountain range and brings the two
populations together again, but when they mate, the resulting hybrids all produce sterile
young. This scenario is an example of - Correct Answers -allopatric speciation
Under the biological species concept, a species is a group of organisms that - Correct
Answers -have the potential to interbreed in nature and produce fertile offspring
Allopatric speciation is not likely to occur when - Correct Answers -several populations
become isolated from one another as drying conditions cause a large body of water to
become separate, smaller bodies of water.
Which of the following would a biologist describe as microevolution? - Correct Answers -
a change in the gene pool of a population from one generation to the next
According to this figure, which pair of organisms shares the most recent common
ancestor?
The figure shows a phylogenetic tree. A common ancestor divides into two branches at
node 1. One of the branches leads to lungfishes and the other leads to node 2. It
divides into two branches as well. One of these branches leads to amphibians and the
other leads to node 3. It divides into two branches, with one of them leading to
mammals and the other leading to node 4. It divides into two branches as well, one of
these branches leads to lizards and snakes and the other leads to node 5. It divides into
two branches and one of them leads to crocodiles and the other leads to node 6. It
divides into two branches which lead to ostriches and hawks, respectively. - Correct
Answers -mammals and crocodiles
Which statement best describes the mode of selection depicted in the figure? - Correct
Answers -directional selection, changing the average color of the population over time
Genetic drift resulting from a disaster that drastically reduces population size is called -
Correct Answers -the bottleneck effect.
In natural selection, _____ determine which phenotypes are successful. - Correct
Answers -current conditions in the local environment
The evolution of populations due to chance is - Correct Answers -genetic drift.
If color is an inherited trait in beetles, and birds are more likely to eat brown beetles than
green beetles, - Correct Answers -the frequency of the green allele will increase.
REVIEW
Multicellular organisms evolved from three different ancestral lineages: stramenopiles,
unikonts, and archaeplastids. Of these, fungi and animals evolved from two different
lineages of ________, and land plants are ________. - Correct Answers -unikonts;
archaeplastids
Chemoautotrophic bacteria obtain their carbon from ________ and their energy from
________. - Correct Answers -CO2; reactions involving inorganic chemicals
Dunaliella salina is a bacterium that is able to live in aqueous solutions with such high
salt concentrations that the salt cannot fully dissolve. D. salina is an example of a(n) -
Correct Answers -extreme halophile.
________ are toxic proteins secreted by pathogenic bacteria, and ________ are toxic
components of the outer membrane of gram-negative bacteria. - Correct Answers -
Exotoxins; endotoxins
Which of the following is a member of the domain Archaea? - Correct Answers -
methanogens
One difference between gram-positive and gram-negative bacteria is that - Correct
Answers -gram-positive bacteria have more peptidoglycan in their cell walls.
The heterokaryotic phase of a fungal life cycle is a - Correct Answers -stage in which
hyphae contain two genetically different haploid nuclei.
Humans are an example of - Correct Answers -chemoheterotrophs
Heterotrophic eukaryotes that digest their food externally and absorb the small
molecules are referred to as - Correct Answers -fungi.
Threadlike fungal filaments are called - Correct Answers -hyphae.
The ultimate source of all new alleles is - Correct Answers -mutation.
Structures that evolved from the same structure in a common ancestor are - Correct
Answers -homologous
, The process through which species not closely related may come to resemble one
another if they live in a similar environment is known as - Correct Answers -convergent
evolution.
Uplift and formation of a mountain range divide a freshwater snail species into two
isolated populations. Erosion eventually lowers the mountain range and brings the two
populations together again, but when they mate, the resulting hybrids all produce sterile
young. This scenario is an example of - Correct Answers -allopatric speciation
Under the biological species concept, a species is a group of organisms that - Correct
Answers -have the potential to interbreed in nature and produce fertile offspring
Allopatric speciation is not likely to occur when - Correct Answers -several populations
become isolated from one another as drying conditions cause a large body of water to
become separate, smaller bodies of water.
Which of the following would a biologist describe as microevolution? - Correct Answers -
a change in the gene pool of a population from one generation to the next
According to this figure, which pair of organisms shares the most recent common
ancestor?
The figure shows a phylogenetic tree. A common ancestor divides into two branches at
node 1. One of the branches leads to lungfishes and the other leads to node 2. It
divides into two branches as well. One of these branches leads to amphibians and the
other leads to node 3. It divides into two branches, with one of them leading to
mammals and the other leading to node 4. It divides into two branches as well, one of
these branches leads to lizards and snakes and the other leads to node 5. It divides into
two branches and one of them leads to crocodiles and the other leads to node 6. It
divides into two branches which lead to ostriches and hawks, respectively. - Correct
Answers -mammals and crocodiles
Which statement best describes the mode of selection depicted in the figure? - Correct
Answers -directional selection, changing the average color of the population over time
Genetic drift resulting from a disaster that drastically reduces population size is called -
Correct Answers -the bottleneck effect.
In natural selection, _____ determine which phenotypes are successful. - Correct
Answers -current conditions in the local environment
The evolution of populations due to chance is - Correct Answers -genetic drift.
If color is an inherited trait in beetles, and birds are more likely to eat brown beetles than
green beetles, - Correct Answers -the frequency of the green allele will increase.
