Biology Questions
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Biology
Biological ClassificationA population of giraffes lives in a specific environment that contains trees of various heights A flood occurs in the area causing the shorter plants to die and only the tall trees to remain After many generations it is found that giraffes living in the environment have longer necks on average than giraffes living in the same environment before the flood Based on the scenario above which type of selection occurred in the population after the flood A B C stabilizing selection directional selection destabilizing selection

Biology
EvolutionMicroevolution describes evolution on its smallest scale such as the change in allele fre quencies in a population over generations Insects and bacteria are key species to observe microevolution due to their short generation cycles Dichlorodiphenyltrichloroethane DDT is an insecticide used in agriculture DDT was widely in use in the United States from the 1940s until 1972 Scientists studied a particular allele frequency in laboratory strains of the common fruit fly Drosophila melanogaster These strains were collected from flies in the wild in the 1930s and zero al leles were found to confer with DDT resistance In the 1960s the frequency was found to be 40 percent conferring DDT resistance Predict what would happen with the frequency of DDT resistance if another round of data collection was to occur in 2030 among Drosophila melanogaster A B C The DDT resistance frequency would neither increase or decrease due to mutation rates altering the gene to match new pesticides The DDT resistance frequency would neither increase or decrease much due to the lack of DDT usage and it not being a selective advantage anymore The DDT resistance frequency would continue to increase at the same rate as it did from 1930 to 1960 The DDT resistance frequency would decrease rapidly back down to zero since DDT is

Biology
The Living WorldAbiogenesis is the process by which living organisms first arose from inorganic materials An explanation for the origin of life must account for the formation of biological molecules such as nucleic acids and proteins Which of the following best describes how scientists have tested hypotheses about form ing the first biological molecules A B C D by dating the oldest known fossils to determine the first living organism by observing interactions of inorganic molecules in today s atmosphere by studying other planets in the solar system to learn about the history of Earth by simulating the predicted conditions of early Earth in a lab

Biology
EvolutionLarge North American vultures known as California condors nearly went extinct during the 1980s due to habitat destruction The number of wild California condors is slowly in creasing due to captive breeding and the reintroduction of populations into the wild However because of the population bottleneck all of the condor populations that now ex ist in the wild are descended from a population of just 14 individual California condors Based on the information above which of the following two claims is best supported for the population bottleneck Select all that apply A B C Due to the bottleneck the wild California condor populations have become more re silient containing individuals whose traits were selected for by natural selection Present wild California condor populations have small amounts of genetic diversity and are therefore at risk of extinction in the wild Due to the bottleneck the wild California condor populations are less likely to contain individuals that can adapt to a certain environmental change habi

Biology
Ecology - EcosystemsWhich statements below are true regarding evidence of evolution such as analogous and homologous structures 1 Structures found in different species with similar functions resulting from a common an cestor are known as analogous structures II Structures found in different species with similar functions resulting from natural selec tion are known as analogous structures III Structures found in different species with similar anatomical forms resulting from natu ral selection are known as homologous structures IV Structures found in different species with similar anatomical forms resulting from a common ancestor are known as homologous structures A B C IV only II and IV Ill only

Biology
EvolutionAll birds living today are descended from a group of dinosaurs called theropods Theropods first appeared in the fossil record around 200 million years ago However fos sils of taxa similar to modern birds can be found in the fossil record from around 66 million years ago The table below provides information about certain traits in theropods and modern birds An X indicates the presence of a trait Trait A Bipedal B Hollow Bones C Feathers Jaws with Sharp Teeth Long Boney Tail Fused Clavicle Reversed First Toe Theropods X X A table that shows the comparison of traits in theropods and modern birds X X Modern Birds X X Each of the answer choices below describes a specific fossil Which fossil provides the strongest evidence for the discovery of a transitional species that existed in the period between theropods and modern birds X X X The fossil of an organism with a reversed first toe and a long bony tail was found in a 145 million year old rock layer The fossil of an organism with feathers and a reversed front toe was found in a 55 mil The fossil of a bipedal organism with hollow bones was found in a 100 million year old rock layer

Biology
Molecular Basis of InheritancePTC or phenylthiocarbamide is a chemical that to humans either tastes bitter or has no taste at all The ability to taste the bitterness of PTC is controlled by a single gene that codes for a bitter taste receptor on the tongue Tasters or individuals that can taste the bit terness of PTC have at least one copy of the dominant allele T Nontasters or individuals who cannot taste the bitterness of PTC must have two copies of the recessive allele t The numbers of tasters and nontasters in the human population are shown in the table below A B Phenotype n Tasters Select all that apply There are 2 correct options D Nontasters Total If the population is in Hardy Weinberg equilibrium which of the following identifies the correct genotype frequencies for the population Number of Individuals 1 762 338 2 100 A total of 2 56 percent of the population are homozygous dominant A total of 13 44 percent of the population are heterozygous A total of 48 percent of the population are heterozygous A total of 36 percent of the population are homozygous dominant

Biology
Ecology - EcosystemsA group of researchers studies fish populations in two adjacent small mountain lakes Seasonal flooding will typically temporarily join the two lakes Interbreeding and isolation between the lakes fish populations can occur when the lakes are joined The climate of the area has become drier so seasonal flooding no longer occurs Which of the following best predicts how the lack of seasonal flooding will affect the fish populations in the lakes over time A B C D The fish population in each lake will become reproductively isolated resulting in al lopatric speciation Genetic drift will increase the genetic diversity within the two lakes fish populations re sulting in sympatric speciation The fish population in each lake will adapt to different resources resulting in sympatric speciation Gene flow between the two lakes fish populations will increase resulting in allopatric

Biology
The Living WorldThe peppered moth Biston betularia comes in two varieties The typica form is white with black spots and was prominent in England prior to the Industrial Revolution while the car bonaria or black variety was seldom seen A century later the carbonaria is the dominant phenotype and typica is less than 2 percent of the peppered moth population Which of the following explanations best describes the evolution of the peppered moth in post industrial England A B C D Environmental changes due to air pollution created a situation where the typica variety was more likely to be seen and eaten by predators making carbonaria variety more fit for the new environment Air pollution caused a unique mutation in the typica variety which caused its offspring to present phenotypically as carbonaria in subsequent generations Due to air pollution from industrial coal burning the typica variety died off allowing more resources for the carbonaria variety Predators which were reducing the population numbers of the carbonaria variety prior to industrialization moved out of the citior dun

Biology
Molecular Basis of InheritanceA scientist is studying two populations of zebra doves in the Hawaiian Islands The two pop ulations are isolated but live in similar environmental conditions Over 20 years scientists gather data on the allele frequency for a specific gene The gene has two alleles D and d A sample of the scientist s results for the allele frequency in the two populations is shown in the table below A Year B 1997 C 2017 Frequency of Allele D 0 68 Population 1 00 Frequency of Allele d A table that shows changes in allele frequencies in two populations 0 32 Which statement is best supported by the data in the table above 0 00 Frequency of Allele D 0 62 Population 2 0 14 Frequency of Allele d Allele D was maintained in Population 1 and Population 2 due to gene flow occurring be tween the two populations Allele D became fixed In Population 1 as a result of random changes that occurred in the population over time Allele d codes for a tralt that was a selective disadvantage to zebra doves in both popu lations during the study period 0 38 0 86

Biology
Ecology - EcosystemsEvolutionary biologists maintain that glycolysis is a metabolic pathway that evolved prior to the divergence of life on Earth into different domains Which of the following best supports this hypothesis of evolutionary biologists A Glycolysis is used by all prokaryotes across taxonomical domains and kingdoms B C D Glycolysis is used by all cells on Earth with a few modifications regardless of taxonomi cal domain Glycolysis occurs in the cytosol of cells rather than within a membrane bound or ganelle so all life forms can metabolize through it Glycolysis is the shortest metabolic pathway and requires no oxygen to be completed lllife forms can accomplish this

Biology
EvolutionDarwin noticed that variations between members of a population when inherited affected the survival and reproductive rates In his book On the Origin of Species Darwin first de scribed the concept of natural selection or the survival of the fittest Which scenario best demonstrates the process of natural selection A A male chipmunk which is the strongest in the group never spends time reproducing because it is busy fighting off predators and competitors for resources B A family of chipmunks lives near a small neighborhood of houses where a human tod dler drops food constantly giving the chipmunks an abundance of food resources which they are able to provide for their offspring C A chipmunk born with sensitive hearing is able to sense predators from farther away than others which allows them to live longer and have several offspring that also share this trait of sensitive hearing D One small group of chipmunks comes across a hole in a house and moves into the attic a warm stable environment and survives a harsh winter while the rest of the chip

Biology
Ecology - EcosystemsPentadactyl limbs are seen across several different species A bat s wing a primate s arm and the front leg of a dog all have similar bone structures based off of pentadactyl limbs Based on this information which of the following conclusions can be drawn A B C D Bats primates and dogs all must experience similar environmental conditions Bats primates and dogs have a common ancestor with pentadactyl limbs Bats primates and dogs all evolved in the same geological time period Bats primates and dogs convergently evolved to the same adaptation

Biology
Plant Physiology - PhotosynthesisOne of the major concerns about climate change is the excess amounts of carbon being re leased into the Earth s atmosphere Although the release of carbon has significantly in creased in the past 100 years there are natural processes in which carbon can be se questered from the atmosphere Which of the following is a natural process that promotes carbon sequestration A B C D photosynthesis by algae burning fossil fuels volcanic eruption methane from cattle

Biology
Ecology - EcosystemsA scientist is studying an African savanna ecosystem located in Serengeti National Park An image of an ecosystem can be seen below An ecosystem that contains various living and nonliving parts The scientist is recording observations about the different parts of the ecosystem Which of the observations correctly identifies a community found within the ecosystem shown in the image above A MARCA B C five zebras one impala two giraffes five zebras three impalas eleven oxpecker birds the rocks the grass the trees the sun and the water

Biology
Plant Physiology - Growth & DevelopmentA scientist discovers that during the wet summer season in the African savanna the eco system typically receives an average of 10 to 30 inches of rainfall per year During this time period a scientist observes that rivers and bodies of water flood and create essential new annual habitats for a variety of plant and animal species Animals gather near rivers and watering holes to consume water while plants absorb the water from the soil Plants lo cated in the African savanna typically lose water quickly through their stomata Which of the following correctly identifies the process in which plants lose water through their stomata A transpiration B precipitation C evaporation

Biology
Anatomy of Flowering PlantsNitrogen exists in the atmosphere similar to carbon However nitrogen cannot be directly absorbed from the atmosphere Instead nitrogen must enter the food chain through the absorption of nitrogen from the soil by plants Which of the following describes a process in the nitrogen cycle that is essential for the ab sorption of nitrogen by plants Select all that apply A B C D Nitrogen fixing bacteria convert nitrogen gas into ammonia Denitrifying bacteria convert nitrogen gas into ammonia Denitrifying bacteria convert nitrate into nitrogen gas Nitrifying bacteria convert ammonia into nitrate

Biology
Ecology - EcosystemsPhosphorus is found in nucleic acids such as DNA and RNA and is thus an essential nutri ent for living organisms Which of the following correctly identifies a reservoir of phospho rus found in ecosystems A atmosphere B C D rocks trees ocean water

Biology
Animal KingdomGolden jackals Canis aureus and tigers Panthera tigris are both native to Southeast Europe There have been instances where golden jackals are banished from the pack Typically golden jackals hunt in packs and therefore are unsuccessful at hunting individu ally Instead of hunting on their own most banished golden jackals will begin following tigers Tigers will kill and eat their fill of prey and then leave the carcass behind Once the tiger leaves the jackal will eat what is left on the carcass Which of the following best describes the symbiotic relationship between golden jackals and tigers A B C D The relationship is an example of mutualism because both the jackal and tiger are bene fitting from the relationship The relationship is an example of commensalism because the jackal benefits but the tiger is unaffected The relationship is an example of competition because the jackal and the tiger compete for the same food source The relationship is an example of parasitism because the jackal is feeding on the left

Biology
Ecology - EcosystemsA golf course in Massachusetts uses a large amount of fertilizer that contains nitrogen Members of the city are concerned about the nitrogen from the fertilizer ending up in local waterways and causing excess algae growth Which of the following processes has the potential to move the nitrogen in the fertilizer into a local waterway A B C nitrogen fixation ammonification runoff

Biology
The Living WorldWhen organisms decompose they become food for decomposers such as bacteria fungi and earthworms These decomposers recycle dead plants and animals into chemical nutri ents that are released back into the soil air and water Which of the following correctly describes the role of decomposition in the carbon cycle Select all that apply A B C D remains contain carbon which will become stuck in the soll and can never enter the car bon cycle again remains contain carbon but all of the carbon is released as gas during the decomposi tion process remains contain carbon that can eventually become fossil fuels which can be burned for energy remains contain carbon that becomes stored in layers of sediment which eventually be orale

Biology
Ecology - EcosystemsOrganisms in an ecosystem can use various methods to obtain energy for survival A porcini mushroom can be found growing near wood from dead trees The mushrooms break down the nonliving organic matter to use as a source of energy Which of the following correctly identifies the type of organism that mushrooms are based on how they obtain energy A B C saprotroph parasite detritivore

Biology
Molecular Basis of InheritanceA hypothetical population of 200 cats has two alleles 7 and 75 for a locus that codes for tail length The table below describes the phenotypes of cats with each possible genotype as well as the number of individuals in the population with each genotype Which statements about the population are true Genotype 7272 TLTS TSTS Phenotype tail length long O medium short Number of individuals in population 60 40 100 Adapted from Biology by Campbell and Reece 2008 Pearson Education Inc Select the five statements that are true View Available Hint s Heterozygotes make up 20 of the population Homozygotes make up 80 of the population Homozygotes make up 30 of the population In the entire cat population 60 of the alleles are 75 In the entire cat population the frequency of the 75 allele is 0 5 In the entire cat population the frequency of the 7 allele is 0 4 Assuming random mating each gamete has a 50 chance of having a Tallele and a 50 chance of having a 75 allele

Biology
Ecology - EcosystemsWhich of the following is an example of an anthropogenic ecosystem disruption A A forest is cleared to become a field where corn will be grown and harvested B A volcano erupts and covers a nearby forest with a thick layer of lava C A hurricane causes flooding which causes various native plants to die D A wildfire burns acres of land and returns nutrients to the soil

Biology
Ecology - EcosystemsThe Great Barrier Reef is the world s largest coral reef system composed of over 2 900 in dividual reefs and 900 islands stretching over 2 300 km In just five years marine heat waves have triggered three mass coral bleaching events reducing shallow water coral reefs by as much as 50 percent Because of the bleaching events the coral reefs have experi enced a loss of species biodiversity How will a loss in species biodiversity affect an ecosystem A B C D The health and stability of an ecosystem are determined only by genetic diversity not by species diversity Although a loss of species diversity is not good for an ecosystem it typically does not af fect the stability of the ecosystem A loss of species diversity reduces the stability of the ecosystem and lowers the health of the ecosystem Only simple ecosystem structures with low species diversity are affected by a loss in species diversity

Biology
Ecology - EcosystemsThe kelp forests are often referred to as the lungs of the ocean since they absorb carbon dioxide and release oxygen through photosynthesis More than 95 percent of California s coastal kelp are gone after being devoured by a population explosion of purple sea urchins in the past eight years Sea otters are foragers that eat mostly hard shelled invertebrates such as sea urchins Although sea otters are not abundant in number they play a vital role in controlling the sea urchin population Based on the information above sea otters are an example of which of the following concepts A B C commensalism resource partitioning keystone species

Biology
Ecology - EcosystemsAn image of the species of trees and the percentage of trees found in two different com munities can be seen in the image below A 25 B C 25 Community 1 The percentage of each tree species found in two communities 25 25 evenness 6 12 Which of the following accurately compares the species richness and species evenness in the two communities Community 2 70 Community 2 has a higher species richness but the same species evenness as Community 2 The two communities have the same species richness but they have different species 12 Community 1 and Community 2 have the same species richness and species evenness

Biology
Ecology - EcosystemsPenguins are typically found living in colonies known as rookeries containing up to a mil lion nesting pairs Penguins often nest swim and feed in groups Which of the following best describes the population density and level of the sociality of a typical penguin population A B C D low population density low sociality high population density high sociality high population density low sociality low population density high sociality

Biology
Ecology - EcosystemsAfrican bush elephants have a lifespan of 60 to 70 years They typically only have one off spring every 4 years with pregnancies lasting up to 2 years Females will remain with their herd for life while males may leave to begin a solitary life at about 12 to 14 years of age Based on this information what type of survivorship curve can be expected for African bush elephants A B C type I survivorship curve type II survivorship curve type III survivorship curve

Biology
Ecology - Organisms & PopulationFour species of warblers live in the same tree habitat Magnolia warblers forage for insects on the lower trunk Black throated green warblers prey on foliage eating insects close to the trunk Blackburnian warblers forage high in the treetops and catch their prey insects on the wing Cape May warblers eat sap or insects gleaned from the bark Which of the following best explains how the competitive exclusion principle relates to the scenario above A B C D All four warblers have some similarities but feed from the same place in the habitat As a result the four species are able to coexist in the same habitat All four warblers have similarities in their beak structure As a result the four species compete directly with one another for food which relates to the competitive exclusion principle All four warblers live in the same habitat and have some similarities but they do not feed from the same place in the habitat As a result the four species can coexist in the same habitat All four warblers have identical beak structures but do not feed from the same places in the habitat As a result the four species do not directly compete for food so they can

Biology
Anatomy of Flowering Plantslarge seedpods after flowering The seed pods are pale green and covered with bumps Eventually the pods turn brown and split open releasing up to 200 flat brown seeds Silky white hairs attached to each seed facilitate wind dispersal An image of milkweed seeds can be seen below A milkweed seed Which of the following correctly identifies the expected pattern of distribution of dandelions based on the in formation above A B C clumped distribution pooled distribution uniform distribution

Biology
Ecology - EcosystemsA research scientist is studying the effect of drought on various species in a woodlands ece system The researcher focuses first on the population of white tailed deer After a year of data collection the researcher determines the current population size is 461 Over the year the population experienced 43 deaths and 92 births Based on this information what is the per capita growth rate for the population A B C D 0 29 white tailed deer per year 0 11 white tailed deer per year 0 09 white tailed deer per year 0 20 white tailed deer per year

Biology
Anatomy of Flowering PlantsWhich of the following statements are correct regarding transpiration and evaporation 1 Transpiration is the evaporation of water from plants II Both terms involve the conversion of liquid water into water vapor III Evaporation occurs when water vapor in the atmosphere changes into liquid water and falls with gravity IV Both processes occur on the surface of plants A B C I only I and IV II and IV

Biology
Molecular Basis of Inheritancein researching whether or not AP biology students who use a test prep book perform better on the exam than those who do not use a test prep book You take 60 random students and give 30 of them a test prep book while the other 30 will use the resources they already have After the students take the exam you analyze the data and find that of the students who used a test prep book 26 passed For the students who used only the resources they already had you found that 12 passed With this data would you suggest to future students to use a test prep book Step 1 state the null hypothesis Step 2 determine your expected values Step 3 complete the Chi square chart Step 4 calculate your degrees of freedom Step 5 interpret results Observed O Expected E O E O E O E E fol Total

Biology
Ecology - EcosystemsA forest fire accidentally started in the San Bernardino Mountains in California All the canyon live oak trees burned down during the forest fire After the fire numerous taller trees replaced the oak trees Which of the following is the best explanation of this event A B C D The burning of the oak trees caused a change in the pH of the soil which did not allow the oak trees to grow back After the fire there was not enough water in the ecosystem to support the growth of large trees such as oak Smaller quicker growing trees will be present after a forest fire before slower growing trees such as oaks are able to develop Oak trees are easily affected by pests which allowed for other pest resistant trees to

Biology
Ecology - EcosystemsA food web representing the organisms in an ecosystem is shown below corn rat A python B A food web of an ecosystem a flowering plant frog grasshopper dragonfly mangoes wolf eagle butterfly lavenders Which of the following organisms can be found in more than one trophic level dragonfly mangoes thrush fruit fly

Biology
Animal KingdomConsider the same researcher from the previous question also collected information on a population of Colorado chipmunks After the first year the researcher found that the cur rent population size is 1 386 and the population experienced 327 deaths and 419 births After a few calculations the scientist found that the chipmunk population had a growth rate of 0 07 Based on this what would be the expected chipmunk population in three years A 1 587 Colorado chipmunks

Biology
Ecology - EcosystemsWhich of the following would have the most negative impact on the nitrogen cycle in an ecosystem A B A farmer decides to plant a new type of crop in the field D A bacteriophage carried by livestock is introduced into the ecosystem C A volcano erupts on a nearby island and produces a large amount of ash A power plant is built nearby which burns coal to produce energy

Biology
Ecology - EcosystemsA food web fox A B rabbit 89 3J owl 8 93J mouse hawk frog grasshopper The trophic level in which the rabbit can be found contains an energy of 893 J Based on this which of the fol lowing correctly identifies how much energy would be available in the trophic level in which the snake can be found grasses snake bird

Biology
Biological ClassificationA specific forest has a gross primary productivity of 187 J m day and 93 J m day worth of carbon dioxide flows out of the forest Based on this information what is the net primary productivity of the forest

Biology
Ecology - Ecosystemscupy less than 1 percent of the ocean floor coral reefs are home to more than 25 percent of all marine life A few organisms found near coral reefs are sea turtles coral butterflyfish and gorgonian corals or soft coral A coral reef ecosystem A Which of the following correctly identifies an example of a community within a coral reef ecosystem B 3 DVL one sea turtle eight butterflyfish and five gorgonian corals one sea turtle C three butterflyfish DUL

Biology
Biological ClassificationWhich of the following statements correctly compares r selected and K selected species A In general K selected species tend to have a longer lifespan than r selected species since K selected species invest more time into caring for their young B In general r selected species must use more energy to care for offspring than K se lected species since r selected species produce large amounts of offspring C In general K selected species are better at surviving in unstable environments since these species put more care into their young to guarantee survival D In general r selected species include organisms such as primates and sharks while K selected species include organisms such as rodents and fish

Biology
Ecology - Biodiversity & ConservationAn ecologist is studying the changes in an ecosystem after the eruption of a volcano The ecologist returns to the area four times over the first year to make observations Which of the following would be the first pioneer species to be seen in the ecosystem af ter the volcano eruption A lichen B C shrubs birds

Biology
Ecology - EcosystemsNitrogen is essential in biomolecules such as proteins and nucleic acids Proteins and nu cleic acids play a role in gene expression and are an important process in all living organisms Which of the following correctly identifies where most nitrogen can be found in an ecosystem A B C atmosphere plants bacteria

Biology
Biological ClassificationThe amount of carbon dioxide in the atmosphere has increased substantially since the be ginning of the industrial era Carbon dioxide concentrations have risen from 280 ppm in the late 1700s to 414 ppm in 2021 which is a 48 percent increase Almost all of this in crease is attributed to human activities Which of the following is true about how increased human activity has affected the carbon cycle A B C D To counteract the increased amount of carbon dioxide in the atmosphere producers must perform photosynthesis at a higher rate Fewer volcanic eruptions have occurred over time due to too much carbon dioxide in the atmosphere Due to the increase in carbon dioxide emissions the ocean has become more acidic over time Acid rain has declined over time due to the increase in carbon dioxide emissions by

Biology
Ecology - Biodiversity & ConservationThe use of certain fertilizers can result in high levels of phosphorus in water used in urban areas Which of the following is a possible negative side effect of excess phosphorus in water A B C higher rates of cellular respiration decrease of algae blooms increase of algae blooms resulting in a decrease of aquatic life

Biology
Ecology - Biodiversity & ConservationA high school student is taking an environmental science class For one assignment the student must go outside their house and observe the surrounding ecosystem The student walks outside and records the following observations It is a sunny day with few clouds in the sky St Augustine grass can be found throughout most of the yard with a few trees scattered around There are squirrels and birds located throughout the trees There is a weeping willow tree by a small pond The water inside the pond is muddy and no aquatic plants can be seen there Large stones and various rocks outline a garden in a section of the yard The soil of the garden is a dark brown color Inside the garden there are onions tomatoes and jalape os growing On the flower of one of the plants there is a butterfly Which of the following correctly identifies abiotic and biotic factors mentioned in the observations A B C D The trees and onions are biotic factors and the water and rocks are abiotic factors The sunlight and weeping willow are abiotic factors and the squirrels and butterfly are biotic factors The rocks and soil are biotic factors and the grass and birds are abiotic factors The squirrel and butterfly are biotic factors and the trees and water are abiotic factors

Biology
Ecology - Biodiversity & ConservationRecently the amount of carbon in the atmosphere has increased Which of the following human activities has directly caused the increase of carbon in the atmosphere A B C D planting trees in urban areas burning of fossil fuels an increase in the average lifespan technology advancements

Biology
Ecology - Biodiversity & ConservationA natural disaster would be classified as which of the following types of factors A density independent B density dependent C exponential

Biology
Ecology - Organisms & PopulationInside human intestines there are various species of microorganisms One species of bac teria synthesizes vitamin K and can outcompete E coli species which are dangerous to hu mans The bacteria species found in the human intestines does not harm its human host in any way and the species benefits from its intestinal habitat Which term best describes the relationship between the bacteria found within the in testines and humans A mutualism B predation C commensalism