ECOL 220
Which of the following is NOT a characteristic of a fixed function? Question 1 options: Insensitive to the environment Specific to particular species (e.g. rare across the tree of life) Controls core biological processes Often disrupted by single, rare mutations.
Specific to particular species (e.g. rare across the tree of life)
A mutation in the DNA may not result in change in protein function because: Many different amino acids share similar chemical properties, so can substitute for one another without altering function of a protein. Changes to the DNA never result in changes to proteins. All mutations are removed by selection. Mutations that change the protein sequence are always compensated for by changes elsewhere in a protein.
Many different amino acids share similar chemical properties, so can substitute for one another without altering function of a protein.
There are more bacterial cells on and in a person than there are human cells. Question 5 options: True False
True
In the tree above, how long ago did humans share a common ancestor with Hylobates? 6 million years ago (Mya) 14 Mya 18 Mya 25 Mya
18 Mya
A disadvantage of phage therapy is: Question 3 options: Phage will only target the pathogen and do not affect non-pathogenic bacteria Phage mutate during replication Phage multiply much faster than the target bacteria Phage are very specific to the target pathogen, so the pathogen must be identified accurately before treatment can begin.
Phage are very specific to the target pathogen, so the pathogen must be identified accurately before treatment can begin.
Explain how the phage and infecting bacteria would "co-evolve" when phage are used for treatment in infections.
Phage reproduces as bacteria reproduces and phage has the ability to adapt mutations. Phage will evolve as bacteria evolves and newly-produced phage will be able to recognize newly-produced bacteria.
If you are a scientist studying a rare disease, which mode of thinking will be useful for understanding its cause? Typological thinking Population thinking Tree-thinking Not thinking
Population thinking
Long-term effects of microbiome disruption early in life might be cause by epgenetic effects. Epigenetic changes are: Question 4 options: modifications to the DNA that have biological effects, but are not inherited from parents or passed down to offspring. mutations to the DNA inherited changes to the DNA
modifications to the DNA that have biological effects, but are not inherited from parents or passed down to offspring.
Antibiotics work by: Question 2 options: killing or slowing the growth of the target organism mimicking essential molecules for the microbe blocking the active sites of essential microbial proteins all of the above
all of the above
Pathogen evasion of the immune system often involves Question 2 options: Altering cell-surface proteins so they are not recognized by the immune system. hiding dormant inside host cells hiding within the genome of the host all of the above
all of the above
SNPs identified as being related to a trait using GWAS can be located: Question 5 options: in the protein-coding part of a gene. in between genes in a genome. in the regulatory regions of a genome. all of the above
all of the above
Which of these diseases could be the result of accumulated environmental effects Question 3 options: Lung cancer caused by second-hand smoke exposure Neuropathy caused by long-term diabetes Joint pain from long-term obesity all of these
all of these
The figure above illustrates a reaction norms for body weight and age. If the reaction norm for individuals living in the 19th century start on the blue line, changes in environment (i.e. genetics stays the same) will cause individuals to: (reaction norm quiz) Question 1 options: jump from the blue line to the red line. stay in the same place on the blue line. move on the graph along the blue line. move to a new line (e.g. new reaction norm).
move on the graph along the blue line.
A mutation that decreases the reproductive success of people that have it by 0.01% is: will never be under selection will always be under selection likely to under natural selection in a large population likely to be under selection in a small population
likely to under natural selection in a large population
The increase in the frequency of diabetes in human populations since the development of agriculture is an example of: mismatch in time mismatch in space Natural Selection Genetic drift
mismatch in time
Horizontal pathogen transmission...... Question 2 options: occurs from person to person through air, water, contact or vector. occurs from parent to child occurs by incorporating DNA from another species occurs only with viruses
occurs from person to person through air, water, contact or vector.
Disease incidence is: Question 2 options: how many people die from a disease in a given period of time. the number of newly diagnosed cases in a time period the fraction of the population afflicted be a disease the chance of getting a disease in a lifetime
the number of newly diagnosed cases in a time period
Which of the following would be a benefit of maturing later? Question 2 options: the potential for more or higher-quality offspring increasing the risk of death before reproducing shortened generation time increased generation time
the potential for more or higher-quality offspring
Diseases of homeostasis arise because: Question 2 options: the systems they affect are not affected by selection. the systems they affect are canalized or unchangeable. the systems they affect are recently evolved. the systems they affect are designed by evolution to be plastic and adjustable.
the systems they affect are designed by evolution to be plastic and adjustable.
How similar is your genome to another person's? (i.e. the percentage of DNA bases that are identical) Question 1 options: 99.9% 80% 50% 20%
99.9%
If a small group of people sailed from Australia and established a colony on a deserted Pacific island, this would be an example of: A Founder Effect Gene flow Natural selection Meiosis
A Founder Effect
Which is a evolutionary risk posed by "imperfect" vaccines like the HPV vaccine. Question 3 options: A: Vaccination reduces competition for strains not affected by the vaccine, increasing their prevalence and virulence. B: Vaccination increases host lifetime, providing more time for strains not affected by the vaccine to be transmitted to a host. C: Vaccination increases the mutation rate of the virus, making it more likely to evolve faster to avoid the vaccine. A and B
A and B
If people living in the 19th century start on the blue line, what could cause people living later to shift to the red line? (reaction norm quiz) Question 2 options: A change in environmental conditions A change in population size. A change in offspring survival A change in the genes underlying these traits
A change in the genes underlying these traits
A Single Nucleotide Polymorphism is: Question 2 options: A deletion of a base in the genome A difference in a single base in a genome A detrimental mutation A beneficial mutation
A difference in a single base in a genome
Which of the following is an example of a fitness "trade-off"? A gene which decreases the age of sexual maturity but also increases the likelihood of dying in childhood A gene which makes an organism have larger numbers of offspring, but devote fewer resources to raising them to adulthood. A gene that makes an organism more attractive to mates and results in a larger family size. A gene that increases the age of sexual maturity and decreases resistance to bacterial infection.
A gene which makes an organism have larger numbers of offspring, but devote fewer resources to raising them to adulthood.
Describe what is meant by a "public good" in evolutionary biology.
A public good is something produced at a cost by an individual that benefits the population as a whole.
The clotting system in human circulatory systems can stop bleeding, but also can cause catastrophic clots (like strokes and embolisms). This is an example of: Question 1 options: Natural selection A mismatch A trade-off A disease caused by genetic causes
A trade-off
Which of these traits is most likely to be under natural selection in humans? A trait that causes near-sightedness which is correctable with glasses or contacts. A trait that causes sickness and death in childhood. A trait that is identical in every person. A trait increases the likelihood of cancer after menopause.
A trait that causes sickness and death in childhood.
Diseases of homeostasis, like diabetes, affect mostly: Question 5 options: Fixed biological systems Adjustable biological systems
Adjustable biological systems
Which below is an example of human niche construction? Question 2 options: Tectonic plate movement Agriculture Ice ages Earthquake
Agriculture
Using lower-dose antibiotics might help reduce the evolution of antibiotic resistance because: Question 1 options: lower doses do not kill off all of the competition for the resistant strains it allows the immune system to do much of the work in killing the infecting microbes lower doses exert weaker selection for resistant strains All of the above
All of the above
A commensal microbe can become a pathogen when: Question 2 options: It infects a species other than its natural host. It gets into a part of the host's body where it does not normally reside. The community of microbes that normally grow with the microbe is disturbed. All of the above.
All of the above.
Which of the following are responsible for some of the mismatches in human populations? Urbanization Modern medicine Agriculture All of the these
All of the these
Disturbances in gut microbe communities have been linked to: Question 2 options: Allergies Obesity Autoimmune diseases All of these
All of these
In the figure above, the blue (or red) lines depict the possible plastic response in humans for the age of maturation in females relative to body weight. Which of the following statements below is true for this figure? (life history quiz) Question 5 options: Natural selection is required for an individual to move along one of the curves. Genetic change is required to for an individual to move along one of the curves. An individual's phenotype can only slide along one of the curves in response to environmental conditions. An individual's phenotype can jump from the red curve to the blue curve given the right environmental conditions.
An individual's phenotype can only slide along one of the curves in response to environmental conditions.
Which of the following are thought to disturb the gut microbial community early in life, having lasting consequences later in life. Question 3 options: Natural (vaginal) birth Antibiotic use in children younger than 2. vaccines Breast feeding
Antibiotic use in children younger than 2.
Why was Rinderpest highly virulent when it was introduced to Africa? Question 4 options: Because humans had introduced the most virulent strains from Eurasia. Because the virus was endemic to Africa and most African animals were already resistant. Because cattle immune systems were very strong and the virus had to be very virulent to survive. Because African animals had no resistance, selection favored fast-growing, highly virulent strains of Rinderpest, which out competed less virulent strains.
Because African animals had no resistance, selection favored fast-growing, highly virulent strains of Rinderpest, which out competed less virulent strains.
Why was Rinderpest not very virulent in is native areas in Eurasia? Question 3 options: Because it was native to Eurasia, those animals had evolved some resistance and the virus evolved lower virulence. The virus had no method of transmission in Eurasia Eurasian animals were immune to Rinderpest. The virus was never introduced to Eurasia.
Because it was native to Eurasia, those animals had evolved some resistance and the virus evolved lower virulence.
Which of the following is an example of an adjustable function in biology? Question 4 options: DNA replication Skeletal structure Blood Pressure Heart structure
Blood Pressure
Which of the following is NOT a characteristic of variable functions in biology? Question 2 options: Affected by many genes Sensitive to the environment Controls core biological processes Varies within and between species.
Controls core biological processes
A very potent source of mismatch in human populations is: Question 1 options: Biological evolution Cultural Change Mutation Geographically restricted populations
Cultural Change
Looking at the figure above it is clear that reproductive success among females is higher among Pitcairn Islanders than among the Dogon of Mali. Which of the following is supported by the data in the figure? Genetic differences likely result in different reproductive success for women. Exposure to environmental toxins results in different reproductive success. Cultural differences (Polygyny vs Monogamy) likely result in different reproductive success for women. Children have a higher mortality rate in the Pitcairn Islands.
Cultural differences (Polygyny vs Monogamy) likely result in different reproductive success for women.
You are interested in whether eye color is under selection in humans. You know that humans vary in reproductive success because of different family sizes. You also know that human eye color varies from green to blue to brown to black. What else do you need to know in order to determine if selection might be acting on eye color? A. There is a correlation between eye color and reproductive success B. If eye color is heritable C. The frequencies of different eye colors in a population. D. Both A and B
D. Both A and B
Which of these events has been a major cause of mismatch in the human populations Question 3 options: A: Industrial Revolution B: The last Ice Age C: Agricultural Revolution D: A and C
D: A and C
Which of these is an example of a fixed function? Question 3 options: blood pressure blood glucose regulation heart rate DNA replication
DNA replication
Which of these best describes a mismatch in space? Question 2 options: Diet changes resulting in diabetes Devastation of Native American populations by small pox after the arrival of Europeans in the New World. Origin and spread of the influenza virus in humans. Lactose intolerance in Asian populations
Devastation of Native American populations by small pox after the arrival of Europeans in the New World.
Antibiotics are effective drugs for treating viral infections. Question 4 options: True False
False
Which of the following would NOT be part of an organism's life history? Question 1 options: Age of maturity. Length of life. Number of offspring. Gene variants found in an individual's genome.
Gene variants found in an individual's genome.
The relative-risk of ischemic heart disease related to birth weight and weight at 1 year. If 100 represents "average" risk, then: Question 2 options: Having a higher birth weight increases risk of ischemic heart disease Weighing more at one year has no effect on the risk of ischemic heart disease Weighing more at one year increases risk of ischemic heart disease Having a higher birth weight decreases risk of ischemic heart disease
Having a higher birth weight decreases risk of ischemic heart disease
Trypanosomes, like the pathogen that causes African sleeping sickness and Chagas Disease, live free in the blood. They evade the immune system by: Question 3 options: Having hundreds of Variable Surface Glycoproteins (VSG) that it changes often to avoid being recognized by the immune system. my mimicking human cell structure. By forming resistant cysts. By releasing compounds that kill immune cells.
Having hundreds of Variable Surface Glycoproteins (VSG) that it changes often to avoid being recognized by the immune system.
Which of the following traits do you think is most heritable? Age at first birth. (Age at which a person has their first child) Economic success. Highest level of education achieved Height
Height
The microbes in the human gut are "coevolved" with humans. In this context, coevolved means: Question 1 options: Humans and gut microbes have influenced each other's evolution. Humans and gut microbes evolved independently. Gut microbes are harmful to humans. Gut microbes are essential to human survival.
Humans and gut microbes have influenced each other's evolution.
In the tree above, which pair of organisms share the most recent common ancestor Hylobates and Colobus Hylobates and Pan Macaca and Gorilla Colobus and Pongo
Hylobates and Pan
Given the figure above, which of the following best describes a "trade-off" between fecundity and survival? (reaction norm quiz) Question 5 options: If R is held constant, increasing resources allocated to fecundity will necessarily decrease the resources used for survival Decreasing R will only affect resources allocated to fecundity. Increasing the resources allocated to survival will not affect resources for fecundity if R also expands at the same rate. If R is constant, decreasing resources for fecundity also decreases resources for survival.
If R is held constant, increasing resources allocated to fecundity will necessarily decrease the resources used for survival
Which choice below could be a reasonable explanation for why cancer rates have increased in the developed world, but not in the developing world? Question 4 options: Developing countries have cleaner environments. Developing countries have better nutrition. Improved hygiene and medical care in the developed world has reduced the frequency of infectious diseases, causing more people to live long enough to develop cancer. developing countries have more "natural" environments.
Improved hygiene and medical care in the developed world has reduced the frequency of infectious diseases, causing more people to live long enough to develop cancer.
In the graph above, what explains the decreasing mortality from infectious disease before the discovery of antibiotics at about 1930? Selection for decreased virulence in pathogens The evolution of increased resistance in human populations evolution of antibiotic resistance Improvements in water quality and sanitation
Improvements in water quality and sanitation
Which of these is best described as a mismatch in time? Question 1 options: One population affected by increased rates of a disease because they have migrated to a new environment. Immigrants to the USA from developing countries experiencing higher rates of allergy and asthma. One population being exposed to a common disease in another population because of migration Increased autoimmune diseases because of reduced exposure to microorganisms.
Increased autoimmune diseases because of reduced exposure to microorganisms.
Which below is not an effect of human niche construction? Question 4 options: Increased rates of infectious disease in modern society Exposure to addictive drugs Air pollution More sedentary lifestyle
Increased rates of infectious disease in modern society
In the figure above, which model would be favored by evolution? (life history quiz) Question 3 options: Model 1 Model 2 both models are equally favorable
Model 2
The genetic code is "redundant" because: Each codon can specify multiple amino acids Codons are groups of four consecutive DNA bases Most amino acids are specified by multiple codons Each amino acid is specified by only a single codon
Most amino acids are specified by multiple codons
Human African populations have the greatest genetic diversity, with non-African populations having mostly a sub-set of the diversity found in Africa. Which of the following is the best explanation for this observation? Question 3 options: Non-African populations experience a lower mutation rate. Non-african populations were founded by a small number of individuals that left Africa. (i.e. Genetic bottleneck) Much of the diversity in people migrating out of Africa was lost because of selection. Non-African populations faced higher death rates.
Non-african populations were founded by a small number of individuals that left Africa. (i.e. Genetic bottleneck)
Which below is the best example of a medical condition with both environmental and genetics components? Question 5 options: Obesity Smoking-related lung cancer Downs Syndrome Sickle-cell Anemia
Obesity
Describe one way humans misuse antibiotics that promotes the evolution of resistance in bacteria.
One way that humans misuse antibiotics is the use of antibiotics for viral infections. Infections like the common cold are caused by viruses, not bacteria, and therefore, antibiotics will not help cure the infection. Instead, the use of antibiotics for an unnecessary reason increases resistance to antibiotics.
The figure above describes a simple model of how resources can be allocated to either reproduction (fecundity) or survival (or growth). If a trait increases the ability of an organism to acquire resources, that will definitely increase the size of which pipe? (reaction norm quiz) Question 4 options: R (acquisition amount) S (survival) C (fecundity) None of them
R (acquisition amount)
What is an evolutionary explanation for why we make "live" vaccines in in non-human hosts (e.g. chicken eggs) Question 5 options: Selection will favor increased virulence in the non-human host, resulting in decreased virulence in humans. The virus will no longer cause an immune response in humans The viral genes are replaced with non-human host genes
Selection will favor increased virulence in the non-human host, resulting in decreased virulence in humans.
Which of the following describes a true "trade-off" between resilience an robustness in an organ system. Question 5 options: Brain tissue is weak but also heals very easily. Skin is damaged relatively easily, but also heals very quickly. Skin is difficult to damage and also difficult to repair. Bones are easily broken and take a long time to heal.
Skin is damaged relatively easily, but also heals very quickly.
Stem cells predispose humans to cancer because: Question 2 options: Stem cells retain the ability to differentiate and move. Stem cells have less resistance to genetic damage. Stem cells make up the majority of cells in the body. Stem cells divide more rapidly than other cells.
Stem cells retain the ability to differentiate and move.
Which was NOT a consequence of Rinderpest introduction to Africa? Question 5 options: Death of most of the domestic cattle in Africa Smallpox outbreaks in humans because of food stress The Rinderpest pathogen evolved to infect humans Increase in the number of man-eating lions
The Rinderpest pathogen evolved to infect humans
Resilience is best defined as: Question 4 options: The ability of a system to return to a healthy state from an unhealthy state. The ability of a system to resist transitioning to an unhealthy state. The ability of a system to resist anything that could make it unhealthy. The complexity of a system.
The ability of a system to return to a healthy state from an unhealthy state.
Ischemia, or inadequate blood supply, rapidly damages organs like the brain, but has much less effect on tissues like muscle. Why? Question 2 options: Muscle has high energetic demands and can only do oxidative metabolism. Brain tissue is more resilient than muscle tissue. Brain tissue is more robust than muscle tissue. The brain has high energy demands and can only do oxidative metabolism.
The brain has high energy demands and can only do oxidative metabolism.
Which of the following is not a beneficial role of microbiota in human health. Question 5 options: The cause infectious disease They mediate digestion of fats and carbohydrates They help to maintain normal immune function They synthesize some vitamins
The cause infectious disease
Genetic drift is: the creation of new genes in a population a result of strong natural selection is not a random process The change of the frequency of genes in a population in the absence of selection.
The change of the frequency of genes in a population in the absence of selection.
Explain how the fact that phage can evolve is both an advantage and a disadvantage of phage therapy.
The fact that phage can evolve is an advantage because as the phage coevolves with the bacteria, it will not be evolve a resistance to bacteria. A disadvantage of phage's ability to evolve is that there is the chance that the phage can evolve to infect commensal bacterium.
If a patient is being treated for an infection with penicillin, and 0.00001% of the infecting bacteria contain a resistance gene against penicillin, what is the most likely possible outcome? The patient will be completely cured after completing the course of antibiotics. The infection will appear to be cured, but return later and be resistant to penicillin. Penicillin will be completely ineffective at treating the infection. The bacteria will evolve resistance to multiple antibiotics.
The infection will appear to be cured, but return later and be resistant to penicillin.
When a host is regularly infected by multiple strains of a pathogen (multiple infection), why does selection favor increased virulence of the pathogen. Question 4 options: The more virulent pathogen will kill the host more slowly. The more virulent pathogens will out grow competing strains of the virus. The more virulent pathogen will kill the host faster. The more virulent pathogen has a higher transmission rate.
The more virulent pathogens will out grow competing strains of the virus.
Which of the following is the best definition of "fitness" in biology? Question 4 options: The relative age an individual first reproduces. The relative length of an individual's life compared to members of the same species. The relative success with which individuals with different traits transmit their genes to the next generation. The number of gametes produced by an organism.
The relative success with which individuals with different traits transmit their genes to the next generation.
Which of the following is NOT a condition under which natural selection will occur? There is variation in the trait of interest. The trait is present at a high frequency in a population. There is a correlation between reproductive success and the trait. The trait is heritable. There is variation in reproductive success.
The trait is present at a high frequency in a population.
Traits like core cellular metabolism show less variation in populations of a species because: Question 3 options: These traits no longer have the same benefit in the modern environment. They are very old traits (e.g. shared among many organisms) and selection has already optimized their function. These genes are protected from mutation. They are not found in all members of a population.
They are very old traits (e.g. shared among many organisms) and selection has already optimized their function.
Which of these afflictions would have an exclusively environmental cause (Category 2). Question 4 options: Cystic Fibrosis Type 2 Diabetes Trauma from a gunshot wound Asthma
Trauma from a gunshot wound
Many mismatches are caused by cultural change moving faster than biological evolution in human populations. Question 3 options: True False
True
If you look at the label on a container of hand sanitizer or antibacterial soap, you'll see that it claims to kill 99.99% of germs (bacteria). Why should this statement concern you after completing this section of the course?
Using hand sanitizer or antibacterial soap that claims to kill 99.99% of germs is concerning because the frequent use of antibacterial products will increase one's resistance to antibiotics. The use of antibacterial soap instead of plain soap is unnecessary as plain soap has the ability to decrease infection rates in equal proportion to antibacterial products.
"Younger" cells have a selective advantage over "older" cells because: Question 4 options: Older cells are slower and less able to avoid predation. Older cells can devote more resources toward reproduction and produce more offspring that younger cells. Younger cells devote more resources to growing than older cells. Young cells can devote more resources toward reproduction and produce more offspring that older cells.
Young cells can devote more resources toward reproduction and produce more offspring that older cells.
The rapid spread and high virulence of small pox among Native American populations following the arrival of Europeans in the New World is an example of: a mismatch in space genetic drift a mismatch in time natural selection
a mismatch in space
The Dutch Hunger Winter inspired the "thrifty phenotype" hypothesis which states that: Question 3 options: There is no link between conditions in utero and the frequency of adult disorders. conditions in utero and in early childhood set trigger developmental switches that affect phenotypes related to the early environment. Selection has favors genes which protect for famine, even when no famine is present. Common disorders like metabolic syndrome or hear disease are entirely genetic
conditions in utero and in early childhood set trigger developmental switches that affect phenotypes related to the early environment.
Which disease is most-likely a disease with solely a genetic cause? (Category 1) Question 1 options: obesity asthma cystic fibrosis malnutrition
cystic fibrosis
An environment with poor nutrition and high infection rates might cause an individual: (reaction norm quiz) Question 3 options: to fall at the same point along the line as an individual with good nutrition and low infection rates. fall along the reaction norm toward the right side of the line. to shift from one reaction norm line to another (e.g. move from blue to red). fall along along the reaction norm to the left side.
fall along the reaction norm toward the right side of the line.
In attempting to explain the high rates of obesity and diabetes in modern human populations, the thrifty genotype hypothesis states: Question 1 options: Our ancestors had more sedentary lifestyles. Our ancestors were in a chronic state of starvation. obesity and diabetes are the result of too much sugar consumption. famines in the history of human evolution resulted in selection for genes that efficiently conserved and stored energy from food.
famines in the history of human evolution resulted in selection for genes that efficiently conserved and stored energy from food.
A Genome-Wide Association Study (GWAS) is used to: Question 4 options: identify the cause of a genetic disease in a single individual. identify the function of genes. find associations between genetic variants (e.g. SNPs) and phenotypes (e.g. diseases or traits). sequence the genome.
find associations between genetic variants (e.g. SNPs) and phenotypes (e.g. diseases or traits).
The frequencies of rare monogenic diseases (e.g. sickle-cell anemia or cystic fibrosis) generally are: Question 3 options: decreasing in frequency because of modern environmental conditions increasing in frequency because of modern environmental conditions independent of the environment decreasing in prevalence because of modern medicine
independent of the environment
Having a highly invasive placenta provides what benefit in humans over animals with less invasive placentas? Question 5 options: invasive placentas cost less energy for the fetus to make. Genes involved in making invasive placentas protect against cancer. Invasive placentas are necessary for animals as large as humans. invasive placentas provide more surface area for nutrient exchange between mother and fetus, allowing the mother to pass more nutrients to the fetus.
invasive placentas provide more surface area for nutrient exchange between mother and fetus, allowing the mother to pass more nutrients to the fetus.
Asymmetric cell divisions results in: Question 1 options: one daughter cell recieving more "old" cell parts than the other daughter cell parental cell parts being equally distributed between daughter cells one daughter cell receiving more DNA than the other daughter cell. one daughter cell being larger than the other daughter cell
one daughter cell recieving more "old" cell parts than the other daughter cell
A Mismatch occurs when: organisms that were well adapted to one environment cannot evolve rapidly enough to adapt to new circumstances. when an organism is well adapted to its environment when an organism inherits a mutation that decreases its reproductive success when a mutation increases the reproductive success of an organism
organisms that were well adapted to one environment cannot evolve rapidly enough to adapt to new circumstances.
Human milk oligosaccharides help promote the colonization the the human gut with beneficial microbes by Question 1 options: killing potentially harmful gut microbes stimulating the immune system of the infant promoting the growth and adherence of beneficial microbes creating a mucus layer in the infant intestine
promoting the growth and adherence of beneficial microbes
Robustness is best defined as: Question 3 options: resistance against transitioning from a healthy to an unhealthy state. The ability to resist all things that can cause an unhealthy state. The complexity of a system. The ability of a system to return to a healthy state after being in an unhealthy state.
resistance against transitioning from a healthy to an unhealthy state
When the myxoma virus was introduced into Australia to control rabbit populations, its virulence decreased because Question 1 options: highly virulent strains outcompeted lower virulence strains because they killed their hosts faster. less virulent strains out-competed more virulent strains in individual rabbits. selection favored less virulent strains because they had better transmission. rabbit immune systems rapidly adapted to the highly virulent virus.
selection favored less virulent strains because they had better transmission.
"Typological thinking" is useful when: the average properties of a thing are much more important than the variation from the norm the variation within a population is more important then the average properties when the organisms relationship to other organisms is the most important thing none of the above
the average properties of a thing are much more important than the variation from the norm
Disease prevalence is: Question 1 options: how many people die from a disease in a given period of time. the fraction of the population afflicted be a disease the number of newly diagnosed cases in a time period the chance of getting a disease in a lifetime
the fraction of the population afflicted be a disease