BIO 102 - FINAL
characteristic of monotremes
lay eggs
derived character
trait that appears in recent parts of a lineage, but not in its older members
Which of the mutualistic relationships are not symbiotic?
A moth lays eggs in a plant's flower and pollinates it during the process. A small fish eats dead skin and parasites on a larger fish.
Which of the statements regarding gene flow are true?
A mountain can act as a barrier to gene flow. Migration out of a population can result in changes in allele frequencies in the population.
What did the Human Microbiome Project demonstrate?
A person walking through a room will leave behind millions of individual microbes from hundreds of species.
Which scenario describes an example of founder effect?
A small number of British colonists occupied a small island between South America and Africa during the early 1800s, establishing a new population. This population has different allele frequencies from the original population of Britain.
Light emitted by the sun is a very high‑energy form of radiation that can easily enter the Earth's atmosphere and warm the Earth's surface. Heat from the Earth's surface that is emitted as infrared radiation is a very low‑energy form of radiation that cannot easily exit the Earth's atmosphere. This phenomenon is known as the greenhouse effect, and it plays a major role in the gradual warming of the Earth. How do increased levels of carbon dioxide (CO2) in the Earth's atmosphere influence the greenhouse effect?
An increase in atmospheric CO2 increases the intensity of the greenhouse effect because atmospheric CO2 traps heat from infrared radiation and keeps it from being released in space.
How are mitochondrial genes typically inherited?
An individual inherits their mitochondrial DNA from their mother.
Select the statement that correctly describes the evolutionary relationships among the domains of life.
Archaea and Eukarya are more genetically similar than Archaea and Bacteria
Which statement best describes a mutualistic species relationship?
Both species increase their fitness by interacting with each other.
What is the major impact of climate change on biomes?
Climate change is making climates more extreme.
Which statement best describes how homologous structures evolve?
Different species may evolve different variations on a basic structure inherited from a common ancestor.
uniform distribution
Distribution where populations are spaced evenly
theory of plate tectonics
Earth's crust is broken into plates that move across the more fluid material below.
What is the primary difference between bacterial and eukaryotic cells?
Eukaryotic cells have membrane‑bound compartments called organelles, whereas bacterial cells do not.
How do scientists use fossils to draw conclusions about the evolution of life on Earth?
Fossils can be dated, providing a timeline for when certain types of life existed on Earth.
Many factors can alter allele frequencies, which leads to evolutionary change. One of these factors is the movement known as gene flow. Which statements correctly describe gene flow?
Gene flow can occur when pollen from one population of a plant species is dispersed by the wind to another nearby population of the same plant species. Gene flow is defined as the movement of genes from one population to another.
bottleneck effect
Genetic drift resulting from the reduction of a population, typically by a natural disaster, such that the surviving population is no longer genetically representative of the original population.
Why is the Archaea domain closer to Eukarya than Bacteria?
Genetically, the Archaea are more similar to Eukarya than Bacteria.
exponential population growth model
Growth of a population in an ideal, unlimited environment, represented by a J-shaped curve when population size is plotted over time.
What does having higher fitness mean in an evolutionary sense?
Individuals with genotypes favorable for current conditions are more likely to survive and reproduce.
Select the statements that accurately describe the effect of natural selection on genetic equilibrium
It can cause an allele to become more abundant in a population if it provides a fitness advantage over other alleles for that trait. It is an evolutionary force that prevents natural populations from being in genetic equilibrium. It can cause a recessive allele for a gene to become fixed in a population
Which scenario describes an example of genetic drift?
Many of the brown, black, and white mice living in a coastal town are killed when a storm causes prolonged flooding. By chance, the small number of mice with brown fur are the only individuals to survive.
Linear Growth Model
Model is arithmetic, w/ constant rate of change
Which statement is a tenet of the out of Africa hypothesis for the origin of modern humans?
Modern humans evolved in Africa and then migrated throughout the world, replacing earlier human populations
Of those listed, select the factor most likely to allow some non‑native species to become invasive.
Native species may not recognize non‑native species as food
Which scenarios describe a keystone species?
On one side of a river, a species of herbivore is found in small numbers. On the other side, it is absent. The side it is found on has 5 times the species diversity compared to the other side. An endangered species of predator becomes extinct. Shortly after, the community structure is disrupted and the species diversity is dramatically reduced.
In a hypothetical population of butterflies, a dominant mutation in an allele that controls wing color has resulted in purple spots developing on the wings. The genetic change is heritable such that the offspring of butterflies who inherit at least one mutated allele will develop purple spots. The population of butterflies inhabits a windy field that contains many purple flowers. Individuals with purple spots are so well camouflaged on the purple flowers that they are eaten less frequently by predators. There are other fields with populations of the same species of butterfly nearby, but purple flowers are less prevalent in these nearby habitat areas. There are no borders between these fields and it is common for individuals from one population to be blown into another population by the wind. Despite the advantage the mutated allele confers to the butterflies in the field with many purple flowers, the mutated allele never occupies 100% of the gene pool and the population of butterflies always contains a mix of individuals with and without purple spots. What is the most likely explanation for why this trait does not spread entirely throughout the population?
Outside alleles enter the population through gene flow.
Which scenario describes an example of the bottleneck effect?
Overhunting of the American bison caused the population to decrease from millions to a few hundred by the late 1800s. Conservation efforts brought the population back up, but there is little genetic diversity
Which of the following is true about plant defenses?
Plants are able to release chemicals that both repel pests and attract the pest's predators.
density independent
Referring to any characteristic that is not affected by population density. ex: pollution, tornadoes, earthquakes
density dependent
Referring to any characteristic that varies according to an increase in population density. ex: predation, disease, emigration
antibiotic resistance
Resistance evolving rapidly in many species of prokaryotes due to overuse of antibiotics, especially in agriculture.
What are the effects of climate change on the global distribution of species?
Species distributions are shifting towards the Earth's poles. Mountain species are migrating to higher elevations.
character displacement
Species evolve non-overlapping traits to avoid competition
generalist species
Species with a broad ecological niche. They can live in many different places, eat a variety of foods, and tolerate a wide range of environmental conditions. Examples are flies, cockroaches, mice, rats, and human beings.
specialist species
Species with a narrow ecological niche. They may be able to live in only one type of habitat, tolerate only a narrow range of climatic and other environmental conditions, or use only one type or a few types of food. ex: koala
competitive exclusion
Strong competition can lead to local elimination of one of the species.
Why are rainforests primarily concentrated around the equator of the Earth?
Sunlight strikes the equator more directly because the surface of the Earth is curved
How can a mass extinction lead to explosive diversification of species?
Surviving species rapidly evolve and diversify to fill empty niches.
If fluctuations in global climate are normal, why are scientists concerned about global warming?
The change is happening at an unprecedented rate.
the human microbiome
The community of microbes living in or on our bodies
How might gene flow between two duck populations impede each population's ability to be best adapted to its local environment?
The introduced alleles may produce traits that cause more harm than good to the resident population.
How do similar structures in the forearms of a human, horse, and bat provide evidence for common ancestry?
The mammals share a common ancestor. The differences in forearm functions have evolved from the same ancestral bone structure.
Which sentence best describes exponential population growth?
The population growth rate is not limited by any external factors
ecosystem ecology
The study of energy flow and the cycling of chemicals among the various biotic and abiotic components in an ecosystem.
Two hypothetical populations of rabbits live on a mountain, one at low elevation and the other at high elevation. Rabbits at the low elevation experience a mild climate and have short fur, whereas rabbits at the high elevation are exposed to cold conditions and have long fur. There are no geographic barriers separating the ranges of the two populations. An ecologist finds that in both the low and high elevation populations, there are a few rabbits that have intermediate fur length. She notes that the rabbits with intermediate fur length can successfully mate and produce offspring with rabbits that have short or long fur. What is the most likely explanation for why some rabbits have intermediate fur length?
There is gene flow between the low and high elevation populations
A population of organisms is said to be in Hardy-Weinberg equilibrium if it is not evolving. In a population that is not evolving, the frequency of alleles, genotypes, and phenotypes remains stable over generations. There are several assumptions that must be true for a population to be in Hardy-Weinberg equilibrium. Select all of the statements that are assumptions of a population in Hardy-Weinberg equilibrium
There is no net mutation of genes. There is no migration in or out of the population. Random mating occurs within the population.
Mosses and liverworts are early colonizers during ecological succession and make the environment more amenable for other species. How do these plants contribute to nitrogen levels in the soil?
They form symbioses with nitrogen‑fixing cyanobacteria.
Because extremophiles are hard to culture outside of their native environments, how do scientists classify and identify specific species?
They use DNA sequencing to identify species via genetic differences
convergent evolution
Two distantly related species independently develop similar traits.
Scientists are continually discovering new species of prokaryotes. Why is DNA testing important in identifying new prokaryotic species?
Unique DNA sequences help to determine if the prokaryote is a new species.
climate change
a change in average weather conditions over a long time period
evolution
a change in the frequency of alleles in a population over time
community
a collection of all the organisms living and potentially interacting in the same geographic area
inbreeding depression
a decrease in fitness of a population as a result of related individuals breeding
population
a group of interacting individuals from one species that inhabit the same geographic area
pathogen
a microorganism or virus that infects a host organism and is capable of causing a disease in the host organism
mutation
a random error in gene replication that leads to a change
ancestral trait
a trait that was present in the ancestor of a group
Hawaiian honeycreepers comprise a number of bird species that are found only on the Hawaiian islands. The images show examples of two distinct honeycreeper species. Each honeycreeper species exhibits phenotypic differences in characteristics, such as beak shape and plumage color. All of the Hawaiian honeycreeper species are believed to have evolved from a common ancestor as the birds began to occupy different ecological niches on the Hawaiian islands. What evolutionary concept best describes what is observed in the Hawaiian honeycreepers?
adaptive radiation
A factor that is density‑independent
affects populations regardless of population size in an area.
A factor that is density dependent:
affects populations to varying extents based on population size in an area.
theory
an established explanation for a phenomenon or group of observations that is testable and is well‑supported by evidence
global warming
an increase in the average temperature of Earth
adaptation
an inherited trait that increases the survival and reproduction of organisms that bear it
Characteristics of estuaries
area where rivers join ocean
Which of these is part of the hominid family?
bonobos, gorillas, humans, orangutans
When two species interact within a habitat, competitive exclusion can be observed if
both species depend on the same limited resource, and one species is a better competitor for that resource.
Identify the parts of the phylogenetic tree.
branch, node, root
What type of body symmetry is found in animals that can move swiftly?
bilateral
movement in the animal kingdom evolved with
body plan with symmetry
extremophiles
can survive in extreme environments
characteristics of eutherians
carry young in placenta, long pregnancy, short nursing time
Hardy-Weinberg equilibrium
condition that occurs when the frequency of alleles in a particular gene pool remain constant over time
What word or phrase did Charles Darwin use to describe evolution in his 1859 book On the Origin of Species?
descent with modification
Individuals of a bird species lay eggs of various brown colors in a depression on the ground. After several generations, the birds lay mostly dark brown eggs.
directional selection
Scale color in a population of lizards ranges from tan through brown. A prolonged drought kills much of the vegetation in the area where the lizards live, exposing light‑colored sandstone. On sandstone, brown lizards are more visible to predators than tan lizards. Within a few generations, the percentage of tan lizards has increased. Conversely, the percentage of brown lizards has decreased. What form of selection has taken place in this population?
directional selection
A white‑winged butterfly population is easily visible against green vegetation. A few individuals in the population have red spots on their wings that resemble the red spots on a species that their predators avoid. A few other individuals have a speckled‑gray pattern on their wings that blends well with the vegetation. Over time, the proportions of red‑spotted and gray‑speckled butterflies increase in the population. Conversely, the proportion of pure white butterflies decreases in the population. What form of selection has taken place in this population?
disruptive (diversifying) selection
Individual plants of a tree species have flowers that range from light pink to dark red. After several generations, most trees have flowers that are either light pink or dark red.
disruptive selection
The absence of membrane-bound organelles in a cell tells you that the cell must be
either from a member of the domain Bacteria or from a member of the domain Archaea.
adaptive radiation
evolution from a common ancestor of many species adapted to diverse environments
disruptive/diversifying selection
favors individuals at opposite ends of phenotypic range
Which types of plants possess true stomata?
ferns, mosses, angiosperms
Which human activity is responsible for overloading the nitrogen and phosphorus cycles?
fertilization of farms causing runoff
What can we learn about vertebrate evolution from Tiktaalik that we did not know before?
how vertebrates evolved tetrapod limbs
Malaria is quite common in sub-Saharan Africa. Conversely, malaria is nonexistent in eastern Europe. Residents in sub‑Saharan Africa have genes that provide resistance to malaria, whereas residents in eastern Europe do not possess this gene. If a small population of people from sub-Saharan Africa move to eastern Europe, which term would best describe this movement?
gene flow
founder effect
genetic drift that occurs after a small number of individuals colonize a new area
Which features allowed early primates to succeed as arboreal insectivores?
grasping fingers and toes, binocular vision
Ecologists approximate that the amount of chemical‑bond energy available to a trophic level over time is only about 10% of that available to the preceding level. The other 90% is transformed or transferred into which items?
heat, dead plants, tissue repair in an organism
Characteristics of oceans
high salinity, 4 zones depending on depth and proximity to shore
In the last few decades, the use of antibiotics and antibacterial cleaning products has increased. What consequences are being seen now as a result of the overuse or misuse of antibiotics?
increase in virulence of once‑controlled bacteria and appearance of bacteria that are immune to antibiotics
clumped distribution
individuals are found in groups or patches within the habitat
Characteristics of lakes
little to no salt, 3 zones depending on depth and amount of sunlight
What type of animal is a dolphin?
mammal
Imagine a population of moths. Some gray moths move into and start mating with a population of white moths. This increases the frequency of genes for gray coloration in the white moths' population. Which evolutionary process does this scenario describe?
migration
conditions necessary for evolution
migration, natural selection, genetic drift, nonrandom mating, mutation
gene flow
movement of alleles from one population to another
Imagine a population of white beetles. Two beetles mate. Due to a DNA replication mistake during gamete production in one of the parents, the beetles' offspring are black. This increases the frequency of genes for black coloration in the population. Which evolutionary process does this scenario describe?
mutation
Imagine a population of beetles. White beetles are easier for birds to see and eat. Black beetles blend into their surroundings, so they are less visible to birds than white beetles. As a result, black beetles are more likely to survive and reproduce, enabling the gene for black coloration to be passed on to the next generation. This increases the frequency of genes for black coloration in the population. Which evolutionary process does this scenario describe?
natural selection
In the late Devonian era, the seas began to recede and the land became more fertile. These environmental changes resulted in the emergence of land-dwelling vertebrates. Some animals are better able to survive and reproduce under changing environmental conditions. This is an example of:
natural selection
stabilizing selection
occurs when intermediate phenotypes are favored by natural selection
directional selection
occurs when natural selection favors one of the extreme variations of a trait
If you were looking for a bacterium, where would expect to find one?
ocean, soil, in plants, on your skin
commensal symbiosis
one organism benefits and the other is unaffected
Which level of ecological study focuses on the function of a single individual?
organismal
random distribution
organisms arranged in no particular pattern
species
organisms that can interbreed in nature to produce healthy offspring
greenhouse gases
ozone and CO2
Nonrenewable resources
petroleum oil, coal, natural gas
Earth's atmosphere has not always contained enough oxygen to support life. What was responsible for enriching Earth's atmosphere with oxygen?
photosynthesis by cyanobacteria
Evolution of pollen and seeds were key evolutionary milestones that allowed for
plants to succeed and diversify on land
Traits common to all cells
plasma membrane, DNA, ribosome
Which level of ecological study focuses on interactions between members of the same species?
population
Boom and Bust Growth Curve
population size rapidly increases and overshoots carrying capacity which causes the population crash
reproductive isolation
prevention of gene flow between two populations due to physical or behavioral barriers
descent with modification
principle that each living species has descended, with changes, from other species over time
extreme thermophiles
prokaryotes that thrive in extremely hot environments, such as hydrothermal vents
What kind of symmetry do echinoderms have?
radial
genetic drift
random change in allele frequencies that occurs in small populations
conditions necessary for Hardy-Weinberg equilibrium
random mating, no genetic drift, no mutation, no natural selection, no migration
Burning fossil fuels disrupts the carbon cycle by
releasing large amounts of stored carbon into the atmosphere
According to the biological species concept definition of a species, what characteristics do individuals belonging to the same species share?
reproduce under natural conditions and produce viable offspring
Where are members of the human microbiome found?
respiratory tract, gut, skin, feces
Bacilli cell shape
rod shaped
Traits unique to eukaryotic cells
rough endoplasmic reticulum, nuclear membrane, mitochondrion
Chemicals produced by plants that are not directly involved in growth or reproduction but that help protect the plant by their impacts on other organisms are called
secondary metabolites
What role does the sun play in most of Earth's ecosystems?
serves as a source of nutrients
Homologous structures
similar structures with similar functions and a common ancestor
Hominin is a group of species that includes modern humans and extinct human‑like species that diverged from the lineage that led to bonobos and chimpanzees. What characteristics do all hominins share that distinguish them from other primates, such as chimpanzees and bonobos?
small, blunt canine teeth joints suited for bipedal walking
A vascular system is the _______.
specialized plant tissues that transport water and nutrients
Cocci cell shape
spherical, round
spiral shaped bacteria
spirilla
Coat color in timber wolves ranges from white to gray to black. In forests and grasslands, shades of gray fur blend in with the vegetation better than white or black fur. White‑ or black‑furred individuals are sometimes driven out of their packs and are rarely allowed to mate. As a result, the majority of wolves have gray fur. What form of selection has taken place in this population?
stabilizing selection
Individuals of a bird species lay between 1 and 20 eggs. Individuals of the bird species lay between 5 and 15 eggs after several generations.
stabilizing selection
organismal ecology
studies how an organism's structure, physiology, and behavior meet environmental challenges
Many organisms must consume others to survive. Which scenarios represent consumptive species interactions?
tapeworms taking nutrients from a human's intestines deer herd eating a few leaves off of each tree or shrub a pod of killer whales killing and eating a sea lion
ecosystem function
the biological and chemical processes and interactions that collectively define an ecological community
resource partitioning
the differentiation of niches that enables similar species to coexist in a community
Which of these are demographic factors that affect the biotic potential of populations?
the frequency of reproductive events the probability of surviving until maturity
habitat
the location in the environment that provides the type of resources an organism requires
inbreeding
the mating of two genetically similar individuals to produce offspring
carrying capacity
the maximum number of individuals that can be sustained in this environment
population density
the number of individuals in a population, per unit area or volume
logistic population growth model
the per capita rate of increase approaches zero as the carrying capacity is reached
Which biome covers approximately 3/4 of the Earth's surface?
the saltwater biome, which includes estuaries
What did Carl Woese use to group organisms into three distinct domains?
the sequence of an rRNA molecule
population ecology
the study of factors that cause populations to increase or decrease
community ecology
the study of interactions between species
biogeography
the study of species distributions across the planet
population genetics
the study of the distribution of genetic traits and the allelic changes that occur within a population
The Cambrian explosion
the sudden diversification of animal life from simple organisms to all of the basic body types known today
radiometric dating
uses isotopes to determine the age of fossils and rocks on a scale of absolute time.
What are two major plant adaptations that were most important in allowing plants to become independent of aquatic habitats?
vascular system and seeds
Renewable resources
wind, sunlight, biodiesel
Which term is not present in bryophytes?
xylem cells
