Biology test 1√ Answers
Genetic change in a population through multiple generations defines which of the following?
a) heredity
b) mitosis
c) phenotype
d) evolution
e) genotype
a) heredity
b) mitosis
c) phenotype
d) evolution
e) genotype
d) evolution
The scientist who published “On the Origin of Species by Means of Natural Selection” in 1859 was
A. Alfred Russel Wallace. B. Jean Lamarck.
C. Georges Buffon.
D. Charles Darwin.
E. Charles Lyell.
A. Alfred Russel Wallace. B. Jean Lamarck.
C. Georges Buffon.
D. Charles Darwin.
E. Charles Lyell.
D. Charles Darwin.
A gradual change from an ancestral type was referred to by Darwin as
A. uniformitarianism.
B. descent with modification.
C. fossils.
D. natural selection.
E. special creation.
A. uniformitarianism.
B. descent with modification.
C. fossils.
D. natural selection.
E. special creation.
B. descent with modification.
According to Darwin, natural selection usually
A. neither preserves nor rejects harmful variations in a population.
B. preserves harmful variations and rejects favorable variations in a population.
C. preserves favorable and harmful variations in a population.
D. preserves favorable variations and rejects harmful variations in a population.
A. neither preserves nor rejects harmful variations in a population.
B. preserves harmful variations and rejects favorable variations in a population.
C. preserves favorable and harmful variations in a population.
D. preserves favorable variations and rejects harmful variations in a population.
D. preserves favorable variations and rejects harmful variations in a population.
The relatively short-term changes in allele frequencies within a species or population is
A. uniformitarianism.
B. artificial selection.
C. microevolution.
D. natural selection.
E. macroevolution.
A. uniformitarianism.
B. artificial selection.
C. microevolution.
D. natural selection.
E. macroevolution.
C. microevolution.
The entire collection of genes and their alleles is a population’s
A. genotype.
B. phenotype.
C. dominant traits.
D. recessive traits.
E. gene pool.
A. genotype.
B. phenotype.
C. dominant traits.
D. recessive traits.
E. gene pool.
E. gene pool.
The mode of natural selection in which one extreme phenotype is fittest and the environment selects against the others is
A. directional selection.
B. disruptive selection.
C. stabilizing selection. D. artificial selection. E. uniformitarianism.
A. directional selection.
B. disruptive selection.
C. stabilizing selection. D. artificial selection. E. uniformitarianism.
A. directional selection.
The three types of natural selection are
A. directional selection, artificial selection, and disruptive selection.
B. directional selection, artificial selection, and normalizing selection. C. disruptive selection, stabilizing selection, and normalizing selection. D. disruptive selection, stabilizing selection, and artificial selection.
E. directional selection, disruptive selection, and stabilizing selection.
A. directional selection, artificial selection, and disruptive selection.
B. directional selection, artificial selection, and normalizing selection. C. disruptive selection, stabilizing selection, and normalizing selection. D. disruptive selection, stabilizing selection, and artificial selection.
E. directional selection, disruptive selection, and stabilizing selection.
E. directional selection, disruptive selection, and stabilizing selection.
Darwin made which observation while on his four-year voyage on the HMS Beagle?
A. More individuals of a population are born than survive to reproduce.
B. Populations grow constantly.
C. Organisms are varied and some variations are inherited.
D. An individual’s chance of survival is random. E. Species do not appear to change over time.
A. More individuals of a population are born than survive to reproduce.
B. Populations grow constantly.
C. Organisms are varied and some variations are inherited.
D. An individual’s chance of survival is random. E. Species do not appear to change over time.
C. Organisms are varied and some variations are inherited.
Darwin obtained which of the following in the Essay on the Principle of Population by Malthus? A. Organisms are varied and some variations are inherited.
B. Populations grow constantly.
C. An individual’s chance of survival is random.
D. Species do not change over time.
E. More individuals of a population are born than survive to reproduce.
B. Populations grow constantly.
C. An individual’s chance of survival is random.
D. Species do not change over time.
E. More individuals of a population are born than survive to reproduce.
E. More individuals of a population are born than survive to reproduce.
If an environment changes rapidly, organisms with ____ will be more likely to survive and reproduce.
A. existing beneficial mutations
B. existing neutral mutations
C. the ability to produce beneficial mutations D. the ability to adapt their genotype
E. the correct allele frequency
A. existing beneficial mutations
B. existing neutral mutations
C. the ability to produce beneficial mutations D. the ability to adapt their genotype
E. the correct allele frequency
A. existing beneficial mutations
The founder effect
A. occurs when large groups of individuals leave their home population and establish new settlements, mating only among themselves.
B. occurs when small groups of individuals leave their home population and establish new settlements, mating only among themselves.
C. occurs when many members of a population die, resulting in a great loss of genetic diversity.
D. occurs when many members of a population reproduce causing too much genetic diversity within the population.
E. does not occur in nature.
A. occurs when large groups of individuals leave their home population and establish new settlements, mating only among themselves.
B. occurs when small groups of individuals leave their home population and establish new settlements, mating only among themselves.
C. occurs when many members of a population die, resulting in a great loss of genetic diversity.
D. occurs when many members of a population reproduce causing too much genetic diversity within the population.
E. does not occur in nature.
B. occurs when small groups of individuals leave their home population and establish new settlements, mating only among themselves.
The bottleneck effect
A. occurs when many members of a population die, resulting in a great loss of genetic diversity.
B. occurs when many members of a population reproduce, causing too much genetic diversity within the population.
C. occurs when small groups of individuals leave their home population and establish new settlements, mating only among themselves.
D. occurs when large groups of individuals leave their home population and establish new settlements, mating only among themselves.
E. does not occur in nature.
A. occurs when many members of a population die, resulting in a great loss of genetic diversity.
B. occurs when many members of a population reproduce, causing too much genetic diversity within the population.
C. occurs when small groups of individuals leave their home population and establish new settlements, mating only among themselves.
D. occurs when large groups of individuals leave their home population and establish new settlements, mating only among themselves.
E. does not occur in nature.
A. occurs when many members of a population die, resulting in a great loss of genetic diversity.
The mode of natural selection in which two or more extreme phenotypes are fitter than the intermediate phenotype is
A. directional selection.
B. stabilizing selection.
C. disruptive selection.
D. artificial selection.
E. uniformitarianism.
A. directional selection.
B. stabilizing selection.
C. disruptive selection.
D. artificial selection.
E. uniformitarianism.
C. disruptive selection.
The mode of natural selection in which extreme phenotypes are less fit than the optimal intermediate phenotype is
A. directional selection.
B. disruptive selection.
C. stabilizing selection.
D. artificial selection.
E. uniformitarianism.
A. directional selection.
B. disruptive selection.
C. stabilizing selection.
D. artificial selection.
E. uniformitarianism.
C. stabilizing selection.
Farmers and horticulturalists bred broccoli, cauliflower, kale, and cabbage from the wild mustard plant through _____.
A. artificial selection
B. evolution
C. genetic drift
D. natural selection
E. sexual selection
A. artificial selection
B. evolution
C. genetic drift
D. natural selection
E. sexual selection
A. artificial selection
Darwin concluded from his observations of nature and readings that
A. individuals compete with one another for limited resources and only the fittest survive.
B. individuals compete with one another for limited resources and only the fittest reproduce.
C. population growth is unlimited, leading to the large numbers of organisms.
D. an individual’s chance of survival and reproduction are mostly due to chance and changes in the environment.
E. species do not change over time.
A. individuals compete with one another for limited resources and only the fittest survive.
B. individuals compete with one another for limited resources and only the fittest reproduce.
C. population growth is unlimited, leading to the large numbers of organisms.
D. an individual’s chance of survival and reproduction are mostly due to chance and changes in the environment.
E. species do not change over time.
B. individuals compete with one another for limited resources and only the fittest reproduce.
A male peacock has enormous tail feathers that it uses in mating displays to attract females. While the tail feathers are an advantage in mating, what is the potential disadvantage of these feathers to the male?
A. The feathers require a lot of energy to produce.
B. Bright feathers make males less susceptible to predation.
C. The feathers make the male more attractive to other males.
D. There are no disadvantages to having large tail feathers.
E. The large tail feathers would make it easier to fly.
A. The feathers require a lot of energy to produce.
B. Bright feathers make males less susceptible to predation.
C. The feathers make the male more attractive to other males.
D. There are no disadvantages to having large tail feathers.
E. The large tail feathers would make it easier to fly.
A. The feathers require a lot of energy to produce.
Sexually dimorphic features do not include
A. colored plumage.
B. intelligence.
C. antlers.
D. body size.
E. None of the answers are correct.
A. colored plumage.
B. intelligence.
C. antlers.
D. body size.
E. None of the answers are correct.
B. intelligence.
Which of the following does NOT lead to natural selection?
A. adaptations
B. adjustments an individual makes during its lifetime
C. heritable traits that lead to an advantage over others
D. beneficial variations in some individuals of a population
E. All answers are correct.
A. adaptations
B. adjustments an individual makes during its lifetime
C. heritable traits that lead to an advantage over others
D. beneficial variations in some individuals of a population
E. All answers are correct.
B. adjustments an individual makes during its lifetime
The process by which new species originate
A. is germination.
B. is extinction.
C. occurred only once in Earth’s history.
D. is speciation.
E. occurred for millions of years but is no longer occurring.
A. is germination.
B. is extinction.
C. occurred only once in Earth’s history.
D. is speciation.
E. occurred for millions of years but is no longer occurring.
D. is speciation.
The process by which species cease to exist
A. has never occurred.
B. is speciation.
C. is extinction.
D. is occurring today at a faster rate than ever before.
E. All answers are correct.
A. has never occurred.
B. is speciation.
C. is extinction.
D. is occurring today at a faster rate than ever before.
E. All answers are correct.
C. is extinction.
The types of living organisms on Earth have changed over time – new species have originated and existing species have disappeared. This is an example of
A. speciation.
B. extinction.
C. macroevolution.
D. alternation of generations.
E. hybridization.
A. speciation.
B. extinction.
C. macroevolution.
D. alternation of generations.
E. hybridization.
C. macroevolution.
Biologists divide mechanisms of reproductive isolation into A. sexual and geographic.
B. prezygotic and sexual.
C. postzygotic and geographic.
D. sexual and postzygotic.
E. prezygotic and postzygotic.
B. prezygotic and sexual.
C. postzygotic and geographic.
D. sexual and postzygotic.
E. prezygotic and postzygotic.
E. prezygotic and postzygotic.
An example of polyploidy is found in a plant
A. having an abnormal number of two or more individual chromosomes.
B. having only one set of chromosomes.
C. having three or more chromosomes.
D. having an abnormal number of one particular chromosome.
E. having three or more sets of chromosomes.
A. having an abnormal number of two or more individual chromosomes.
B. having only one set of chromosomes.
C. having three or more chromosomes.
D. having an abnormal number of one particular chromosome.
E. having three or more sets of chromosomes.
E. having three or more sets of chromosomes.
The idea that evolution proceeds in small, incremental changes over many generations is
A. temporal isolation.
B. gradualism.
C. punctuated equilibrium.
D. hybrid breakdown.
E. mechanical isolation.
A. temporal isolation.
B. gradualism.
C. punctuated equilibrium.
D. hybrid breakdown.
E. mechanical isolation.
B. gradualism.
The idea that evolution proceeds with long periods of stasis with relatively brief bursts of fast evolutionary change is
A. temporal isolation.
B. mechanical isolation.
C. gradualism.
D. punctuated equilibrium.
E. hybrid breakdown.
A. temporal isolation.
B. mechanical isolation.
C. gradualism.
D. punctuated equilibrium.
E. hybrid breakdown.
D. punctuated equilibrium.
Species such as mice have a better chance of surviving sudden environmental change than elephants because
A. elephants reproduce much more slowly than mice.
B. elephants require larger habitats than mice.
C. elephants eat more than mice.
D. elephants live longer than mice.
E. elephants have a more selective diet than mice.
A. elephants reproduce much more slowly than mice.
B. elephants require larger habitats than mice.
C. elephants eat more than mice.
D. elephants live longer than mice.
E. elephants have a more selective diet than mice.
A. elephants reproduce much more slowly than mice.
It is believed that the two main reasons for mass extinctions in Earth’s history have been
A. collision between Earth and a large celestial body and human intervention.
B. global warming and human intervention.
C. human intervention and shifting of Earth’s continents.
D. global warming and shifting of Earth’s continents.
E. collision between Earth and a large celestial body and shifting of Earth’s continents.
A. collision between Earth and a large celestial body and human intervention.
B. global warming and human intervention.
C. human intervention and shifting of Earth’s continents.
D. global warming and shifting of Earth’s continents.
E. collision between Earth and a large celestial body and shifting of Earth’s continents.
E. collision between Earth and a large celestial body and shifting of Earth’s continents.
Phylogenetics
A. is the study of evolutionary relationships among species.
B. is the science of describing, naming, and classifying species. C. are inherited attributes.
D. are features only found in living species.
E. are species unrelated and used for comparison.
A. is the study of evolutionary relationships among species.
B. is the science of describing, naming, and classifying species. C. are inherited attributes.
D. are features only found in living species.
E. are species unrelated and used for comparison.
A. is the study of evolutionary relationships among species.
Bacteria cannot be classified using the biological definition of a species for which reason? A. The DNA sequences of all bacteria are more than 97% identical.
B. Bacteria cannot reproduce.
C. Bacteria are present everywhere and cannot be reproductively isolated from other bacteria.
D. Bacteria are asexual.
E. Bacteria do not evolve.
B. Bacteria cannot reproduce.
C. Bacteria are present everywhere and cannot be reproductively isolated from other bacteria.
D. Bacteria are asexual.
E. Bacteria do not evolve.
D. Bacteria are asexual.
Closely related plant species that attract different pollinators resulting in reproductive isolation is an example of
A. sympatric speciation.
B. allopatric speciation.
C. hybrid inviability.
D. hybrid infertility.
E. hybrid breakdown.
A. sympatric speciation.
B. allopatric speciation.
C. hybrid inviability.
D. hybrid infertility.
E. hybrid breakdown.
A. sympatric speciation.
What force leads to the evolution of a new species?
A. All answers are correct.
B. prezygotic reproductive barriers
C. postzygotic reproductive barriers
D. compiled microevolution events
E. large amount of genetic divergence
A. All answers are correct.
B. prezygotic reproductive barriers
C. postzygotic reproductive barriers
D. compiled microevolution events
E. large amount of genetic divergence
A. All answers are correct.
Evolution of a new species occurs
A. in sexually-reproducing organisms.
B. in asexually-reproducing organisms.
C. typically over long periods of time.
D. All answers are correct.
E. allopatrically and sympatrically.
A. in sexually-reproducing organisms.
B. in asexually-reproducing organisms.
C. typically over long periods of time.
D. All answers are correct.
E. allopatrically and sympatrically.
D. All answers are correct.
15. What is the most inclusive level of the hierarchical classification scheme?
A. domain
B. phylum
C. kingdom
D. genus E. species
A. domain
B. phylum
C. kingdom
D. genus E. species
A. domain
Which of the following is true of prokaryotes?
A. Prokaryotes have a nucleus.
B. Prokaryotes are single-celled.
C. Prokaryotes do not have a chromosome.
D. Prokaryotes have membrane-bounded organelles.
E. Prokaryotes do not have ribosomes.
A. Prokaryotes have a nucleus.
B. Prokaryotes are single-celled.
C. Prokaryotes do not have a chromosome.
D. Prokaryotes have membrane-bounded organelles.
E. Prokaryotes do not have ribosomes.
B. Prokaryotes are single-celled.
The domain (domains) that contain prokaryotes is (are)
A. Archaea.
B. Bacteria.
C. both Archaea and Bacteria.
D. Eukarya.
E. both Bacteria and Eukarya.
A. Archaea.
B. Bacteria.
C. both Archaea and Bacteria.
D. Eukarya.
E. both Bacteria and Eukarya.
C. both Archaea and Bacteria.
The region of a prokaryotic cell where the bacterial chromosome (DNA) is located in the A. cell membrane.
B. nucleus.
C. cell wall.
D. nucleoid.
E. ribosome.
B. nucleus.
C. cell wall.
D. nucleoid.
E. ribosome.
D. nucleoid.
DNA that is separate and apart from the chromosome in a prokaryote is a(n)
A. ribosome.
B. endospore.
C. nucleus.
D. nucleoid.
A. ribosome.
B. endospore.
C. nucleus.
D. nucleoid.
E. plasmid.
The rigid barrier that surrounds most prokaryotes is the A. cell membrane.
B. flagellum.
C. ribosome.
D. cell wall.
E. cytoplasm.
B. flagellum.
C. ribosome.
D. cell wall.
E. cytoplasm.
C. ribosome.
The three most common shapes of bacteria are
A. spirillum, endospore, and peptidoglycan.
B. bacillus, spirillum, and coccus.
C. cubical, spiral, and thread-like.
D. spirillum, nucleiod, and peptidoglycan.
E. cubical, spherical, and rod-shaped.
A. spirillum, endospore, and peptidoglycan.
B. bacillus, spirillum, and coccus.
C. cubical, spiral, and thread-like.
D. spirillum, nucleiod, and peptidoglycan.
E. cubical, spherical, and rod-shaped.
B. bacillus, spirillum, and coccus.
Prokaryotes lack which of the following?
A. a nucleus
B. RNA
C. DNA
D. a cell membrane
E. a cell wall
A. a nucleus
B. RNA
C. DNA
D. a cell membrane
E. a cell wall
A. a nucleus
Cyanobacteria are phototrophic. Which of the following would they also be considered?
A. heterotrophic
B. autotrophic
C. chemotrophic
D. obligate anaerobes
E. aerobic
A. heterotrophic
B. autotrophic
C. chemotrophic
D. obligate anaerobes
E. aerobic
B. autotrophic
Which protists produce much of the Earth’s oxygen?
A. amoeba
B. slime molds
C. algae
D. protozoa
E. radiolarians
A. amoeba
B. slime molds
C. algae
D. protozoa
E. radiolarians
C. algae
In the ecosystems of the world, fungi act primarily as
A. decomposers.
B. autotrophs.
C. primary consumers.
D. secondary consumers.
E. photosynthesizers.
A. decomposers.
B. autotrophs.
C. primary consumers.
D. secondary consumers.
E. photosynthesizers.
A. decomposers.
Associations of fungi and plant roots are called
A. pili.
B. mycorrhizae.
C. lichens.
D. root forks.
E. endophytes.
A. pili.
B. mycorrhizae.
C. lichens.
D. root forks.
E. endophytes.
B. mycorrhizae.
A lichen is made up of which two types of organisms?
A. a fungus and a plant
B. a plant and a cyanobacterium
C. a fungus and an alga or cyanobacterium
D. an alga and a bacterium
E. an alga and a plant
A. a fungus and a plant
B. a plant and a cyanobacterium
C. a fungus and an alga or cyanobacterium
D. an alga and a bacterium
E. an alga and a plant
C. a fungus and an alga or cyanobacterium
Why are lichens a good indicator of environmental quality?
A. They cannot absorb toxins.
B. If the air is polluted they cannot get enough sunlight for photosynthesis.
C. They cannot excrete absorbed toxins.
D. If the soil is polluted they cannot produce roots.
E. Toxins inhibit their reproduction.
A. They cannot absorb toxins.
B. If the air is polluted they cannot get enough sunlight for photosynthesis.
C. They cannot excrete absorbed toxins.
D. If the soil is polluted they cannot produce roots.
E. Toxins inhibit their reproduction.
C. They cannot excrete absorbed toxins.
Unlike plant cells, fungal cells lack which of the following?
A. mitochondria
B. chloroplasts
C. cell walls
D. nuclei
E. cytoplasm
A. mitochondria
B. chloroplasts
C. cell walls
D. nuclei
E. cytoplasm
B. chloroplasts
A protist is defined as
A. mostly multicellular eukaryotes that obtain food by external digestion. B. entirely multicellular eukaryotes that obtain food by ingestion.
C. mostly multicellular eukaryotes that obtain food by photosynthesis. D. mostly unicellular eukaryotes that obtain food by photosynthesis.
E. eukaryotic organisms that are not plants, fungi, nor animals.
A. mostly multicellular eukaryotes that obtain food by external digestion. B. entirely multicellular eukaryotes that obtain food by ingestion.
C. mostly multicellular eukaryotes that obtain food by photosynthesis. D. mostly unicellular eukaryotes that obtain food by photosynthesis.
E. eukaryotic organisms that are not plants, fungi, nor animals.
E. eukaryotic organisms that are not plants, fungi, nor animals.
The “Cambrian explosion” refers to
A. the mass extinction of dinosaurs.
B. the origination of all major phyla of animals.
C. the development of the first true cell.
D. the origination of life.
E. the creation of Earth.
A. the mass extinction of dinosaurs.
B. the origination of all major phyla of animals.
C. the development of the first true cell.
D. the origination of life.
E. the creation of Earth.
B. the origination of all major phyla of animals.
An invertebrate is an animal that
A. does not have a backbone.
B. has a backbone.
C. has a complete digestive tract.
D. has an incomplete digestive tract. E. does not have true tissues.
A. does not have a backbone.
B. has a backbone.
C. has a complete digestive tract.
D. has an incomplete digestive tract. E. does not have true tissues.
A. does not have a backbone.
A vertebrate is an animal that
A. has a complete digestive tract.
B. does not have a backbone.
C. has a backbone.
D. has an incomplete digestive tract. E. does not have true tissues.
A. has a complete digestive tract.
B. does not have a backbone.
C. has a backbone.
D. has an incomplete digestive tract. E. does not have true tissues.
C. has a backbone.
Which of the following characteristics do all animals share? A. They are single-celled eukaryotes.
B. They are multi-cellular prokaryotes.
C. They are multi-cellular eukaryotes.
D. They are single-celled prokaryotes.
B. They are multi-cellular prokaryotes.
C. They are multi-cellular eukaryotes.
D. They are single-celled prokaryotes.
C. They are multi-cellular eukaryotes.
The embryonic germ layer of tissue in animals that develops into the skin and nervous system is the
A. pachyderm.
B. endoderm.
C. mesoderm.
D. protoderm.
E. ectoderm.
A. pachyderm.
B. endoderm.
C. mesoderm.
D. protoderm.
E. ectoderm.
E. ectoderm.
The embryonic germ layer of tissue in animals that develops into the digestive tract and organs derived from the digestive tract is the
A. pachyderm.
B. ectoderm.
C. mesoderm.
D. endoderm.
E. protoderm.
A. pachyderm.
B. ectoderm.
C. mesoderm.
D. endoderm.
E. protoderm.
D. endoderm.
The embryonic germ layer of tissue in animals that develops into the muscles and reproductive system is the
A. pachyderm.
B. ectoderm.
C. mesoderm.
D. endoderm.
E. protoderm.
A. pachyderm.
B. ectoderm.
C. mesoderm.
D. endoderm.
E. protoderm.
C. mesoderm.
The type of body symmetry in which any plane passing through the body from the mouth to the opposite end divides the body into mirror images is
A. longitudinal symmetry.
B. mirrored symmetry.
C. bilateral symmetry.
D. radial symmetry.
E. asymmetry.
A. longitudinal symmetry.
B. mirrored symmetry.
C. bilateral symmetry.
D. radial symmetry.
E. asymmetry.
D. radial symmetry.
The type of body symmetry in which only one plane divides the body into mirror images is A. radial symmetry.
B. bilateral symmetry.
C. longitudinal symmetry.
D. mirrored symmetry.
E. asymmetry.
B. bilateral symmetry.
C. longitudinal symmetry.
D. mirrored symmetry.
E. asymmetry.
B. bilateral symmetry.
A circulatory system that keeps blood confined within vessels after leaving the heart is
A. a closed circulatory system.
B. a gastrovascular cavity.
C. an open circulatory system.
D. an incomplete circulatory system. E. a complete circulatory system.
A. a closed circulatory system.
B. a gastrovascular cavity.
C. an open circulatory system.
D. an incomplete circulatory system. E. a complete circulatory system.
A. a closed circulatory system.
A circulatory system in which the heart pumps blood to tissues throughout the body cavity is A. a closed circulatory system.
B. a gastrovascular cavity.
C. an incomplete circulatory system.
D. a complete circulatory system.
E. an open circulatory system.
B. a gastrovascular cavity.
C. an incomplete circulatory system.
D. a complete circulatory system.
E. an open circulatory system.
E. an open circulatory system.
An animal whose body temperature tends to fluctuate with the external environment is a(an)
A. thermophile.
B. mesophile.
C. amniote.
D. endotherm.
E. ectotherm.
A. thermophile.
B. mesophile.
C. amniote.
D. endotherm.
E. ectotherm.
E. ectotherm.
An animal that maintains its body temperature by using heat generated from its own metabolism is a(an)
A. endotherm.
B. ectotherm.
C. thermophile.
D. mesophile.
E. amniote.
A. endotherm.
B. ectotherm.
C. thermophile.
D. mesophile.
E. amniote.
A. endotherm.
Which of the following is a trait shared by mammals and reptiles that is not shared by the other groups of chordates?
A. hair
B. mammary glands
C. an amnion
D. legs
E. lungs
A. hair
B. mammary glands
C. an amnion
D. legs
E. lungs
C. an amnion
Why are animals important?
A. All answers are correct.
B. provide food sources
C. pollinate plants
D. break down organic matter
E. play role as predators
A. All answers are correct.
B. provide food sources
C. pollinate plants
D. break down organic matter
E. play role as predators
A. All answers are correct.
Artificial selection versus natural selection.
Artificial selection – human chooses one or a few desired traits and then allows only the individuals that best express those qualities to reproduce.
In natural selection, environmental factors cause the differential reproductive success of individuals with particular genotypes.
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Genetic drift (founder effect, bottleneck effect).
Genetic drift – change in allele frequencies that occurs purely by chance.
Founder effect – reduction in genetic diversity that occurs when small number of individuals establish a new, isolated population.
Genetic bottleneck – reduction in genetic diversity that occurs if a disaster drastically reduces the size of a population.
Definition of gene pool
gene pool – the entire collection of genes and alleles.
definition of microevolution
genetic changes within a population or species in a short time
definition of macroevolution
emergence of new species in a Longer time span.
equation of natural selection
Overproduction and competition +individual variation
=
unequal reproductive success
=
unequal reproductive success
Modern synthesis
the integration of Darwin’s work on natural selection with Mendel’s work on heredity.
definition of fitness
in a biological context, means that an organism successfully contributes its genes to future generations.
Definition of species
a population or group of populations whose members can interbreed and produce fertile offspring.
Definition of prezygotic and postzygotic reproductive barriers
Prezygotic Barriers Prevent Fertilization
• Occur before formation of a zygote (fertilized egg in which the two haploid nuclei have merged into a single diploid nucleus).
– Postzygotic Barriers Prevent Development of a Fertile Offspring
• Hybrid offspring (offspring of two different species) fail to survive to maturity or cannot reproduce.
• Occur before formation of a zygote (fertilized egg in which the two haploid nuclei have merged into a single diploid nucleus).
– Postzygotic Barriers Prevent Development of a Fertile Offspring
• Hybrid offspring (offspring of two different species) fail to survive to maturity or cannot reproduce.
Allopatric and sympatric speciation
Allopatric Speciation Reflects a Geographic Barrier
(congo river lab)
(congo river lab)
Sympatric Speciation Occurs in a Shared Habitat
• May occur due to differences in habitat within a small geographic area.
– Differences in soil type, temperature, water speed, salinity, etc.
Differences between phyletic gradualism and punctuated equilibrium.
gradualism- evolution proceeds in small steps over many generations.
equilibrium- brief bursts of rapid evolution between long periods of little/no change.
Differences between prokaryotes and eukaryotes.
prokaryotes have no memrane bound organelles, no nucleus (only a nuclear region), and they are typically unicellular arganisms. Eukaryotic are more highly evolved. They have memebrane bound organelles (including but not limited to the mitochondria, chloroplast, golgi apparatus, smooth and rough endoplasmic reticulum), and they have a membrane bound nucleus. Also the structure of their flagella and cilia differ greatly.
autotroph,
heterotroph, phototroph, chemotroph
heterotroph, phototroph, chemotroph
Autotrophs – acquire carbon from inorganic sources such as carbon dioxide.
• Plants and algae.
• Heterotrophs – obtain carbon by consuming organic molecules produced by other organisms.
• Methods for acquiring energy:
• Phototrophs – derive energy from the sun.
• Chemotrophs – derive energy from oxidizing (taking electrons from) organic or inorganic substances.
• Plants and algae.
• Heterotrophs – obtain carbon by consuming organic molecules produced by other organisms.
• Methods for acquiring energy:
• Phototrophs – derive energy from the sun.
• Chemotrophs – derive energy from oxidizing (taking electrons from) organic or inorganic substances.
define protitist and some examples
Eukaryote that does not fit the description of a plant, animal, or fungus.
ex- algae,Dinoflagellates protozoa
ex- algae,Dinoflagellates protozoa
Characteristics of a fungus
eukaryote that obtains food through external digestion.
• More closely related to animals than plants.
• Cannot perform photosynthesis.
• Share many chemical and metabolic features with animals.
• More closely related to animals than plants.
• Cannot perform photosynthesis.
• Share many chemical and metabolic features with animals.
Definition of coelom, advantages of a coelom.
fluid-filled cavity that forms completely within the mesoderm.
Flexibility – internal organs push into the coelom; the fluid of the coelom cushions the organs, protects them, and enables them to shift as the animal moves.
Flexibility – internal organs push into the coelom; the fluid of the coelom cushions the organs, protects them, and enables them to shift as the animal moves.
Complete and incomplete digestive tract.
Incomplete digestive tract – mouth takes in food and ejects wastes.
Complete digestive tract – food passes in one direction from mouth to anus
Complete digestive tract – food passes in one direction from mouth to anus
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