Bio: Unit 3 Quizes

What is the ultimate source of energy for most ecosystems? A. autotrophs B. heterotrophs C. lightning D. the Earth's molten core E. the sun

E. the sun

What is the estimated cost of damage caused by eutrophication in the US? A. $2.2 billion annually B. $2.2 million annually C. $1.1 billion annually D. $1.1 million annually

A. $2.2 billion annually

Which of the following is NOT a hypothesized effect of direct or indirect interactions with mice and other small rodents in the "Of Mice and Mast" article? A. Humans make more use of oak forests during masts, because they hunt the deer that move into those forests during mast events. B. The prevalence of the Lyme disease bacteria (Borrelia burgdorferi) is greater in oak forests during a mast. C. Tick prevalence increases as mice prevalence increases. D. Tick prevalence increases in oak forests during mast events. E. Mice produce more offspring when there are more available acorns.

A. Humans make more use of oak forests during masts, because they hunt the deer that move into those forests during mast events.

What are the units of primary production in this figure? Are they units considering mass or energy? kgC/m2/year A. Mass per unit area per unit time; matter B. Joules per unit area per unit time; energy C. Mass per unit area per unit time; energy D. Joules per unit area per unit time; matter

A. Mass per unit area per unit time; matter

Which of the following was/were a major finding of the study that looked at how the microbiome is initially colonized, looking at microbes in babies and on their moms? (choose all that apply) A. The microbiome of a baby is different depending on whether it was delivered vaginally or by cesarean section. B. Many babies are delivered via cesarean section. C. Babies delivered vaginally have microbiomes that are more diverse than babies that were delivered via cesarean section. D. Babies acquire their microbiome from their mom at birth. E. The oral mucosa microbiome is very similar to the skin microbiome.

A. The microbiome of a baby is different depending on whether it was delivered vaginally or by cesarean section. D. Babies acquire their microbiome from their mom at birth.

What causes the host range of a virus to increase? A. The virus gains entry into a new host cell through random mutation of the virus's genetic material. B. The size of the virus changes over time and allows the virus to infect a different host cell. C. Changes in the human genome over time make humans more susceptible to infection by different kinds of viruses. D. The virus integrates with another virus to gain the DNA sequences that allow infection of a new host cell. E. None of the answer options is correct.

A. The virus gains entry into a new host cell through random mutation of the virus's genetic material.

Which of the following represents a way that viruses are classified? (Choose all that apply) A. Whether they use DNA or RNA as their nucleic acid B. Whether they are single or double-stranded C. The type of host they infect D. Whether they are in Domain Archaea or Domain Bacteria

A. Whether they use DNA or RNA as their nucleic acid B. Whether they are single or double-stranded C. The type of host they infect

The name of the proteins that tag infectious particles for disposal by the immune system is: A. antibodies B. germ cells C. antigens D. G cells E. stem cells

A. antibodies

The second law of thermodynamics states that ____________. A. energy transfers are not 100% efficient B. only eukaryotic cells can produce ATP C. energy cannot be created or destroyed

A. energy transfers are not 100% efficient

A cyanobacterial bloom occurred in Lake Erie near Toledo in summer 2014. This bloom was characteristic of a state of excessive algal growth that is known as ... A. eutrophication B. oligotrophication C. sedimentation D. productivity E. secondary productivity

A. eutrophication

What is the total amount of chemical energy produced by photosynthesis or chemosynthesis in a particular ecosystem? A. gross primary production B. respiration C. total primary production D. net primary production

A. gross primary production

A cell in which viral reproduction occurs is called a: A. host cell. B. somatic cell. C. sex cell. D. daughter cell. E. None of the answer options is correct.

A. host cell.

Choose all that apply. In epidemiology, the basic reproductive ratio, Ro, _________________________. A. is influenced by the duration of the infectious period B. is not influenced by contact rates of infected and non-infected humans C. is low for infectious diseases that are difficult to control D. is influenced by transmission efficiency E. is less than 1 for diseases that will spread through a human population

A. is influenced by the duration of the infectious period D. is influenced by transmission efficiency

Cyanobacteria, milkweed plants, and oak trees are all considered: A. primary producers. B. decomposers. C. secondary consumers. D. primary consumers. E. tertiary consumers.

A. primary producers.

Consider the following chronology of events: no soil community, bacteria and fungi colonize, lichens arrive, mosses arrive, organic matter builds up in soil, small herbs and wildflowers arrive, shrubs start growing, small trees start growing, tall trees grow. What is the best description of the process that is occurring? A. primary succession B. disturbance C. symbiosis D. secondary succession E. island biogeography F. coevolution

A. primary succession

The reasoning behind the use of fecal transplants from healthy individuals is: A. the competition from the introduction of other bacteria into the gastrointestinal tract keeps C. difficile numbers down. B. antibiotics are administered with the fecal transplant, thus controlling populations of C. difficile. C. the fecal matter from healthy patients does not have C. difficile. D. C. difficile feeds on other bacteria that are introduced with the fecal transplant.

A. the competition from the introduction of other bacteria into the gastrointestinal tract keeps C. difficile numbers down.

To measure species diversity in a community, what would you need to know? Choose all that apply. A. the number of species B. the genetic diversity of each species C. the competitive ability of each species D. the geographic range of each species E. the primary productivity of each species F. the relative abundance of each species

A. the number of species F. the relative abundance of each species

Terrestrial autotrophs typically obtain their carbon from: A. ATP. B. CO2. C. CH4. D. CH3OH. E. C6H12O6.

B. CO2

Which of the following statements regarding fires is TRUE? A. They are important components of healthy ecosystems in the western US. B. Certain species are adapted to take advantage of the disturbances created by fires. C. Their frequency has increased greatly in the past century. D. The intensity of fires like those experienced at Yellowstone means that the community needs to undergo primary succession after the fire. E. All of the choices are correct.

B. Certain species are adapted to take advantage of the disturbances created by fires.

Which of the following are NOT correct about the HIV virus? Choose all incorrect statements. A. HIV attacks the immune system directly by infecting T cells B. HIV has a DNA genome C. HIV is an enveloped virus D. HIV is a retrovirus E. HIV infection can be cured by vaccination F. HIV has reverse transcriptase G. HIV has a viral protein coat

B. HIV has a DNA genome E. HIV infection can be cured by vaccination

____________ are organisms that derive carbon from organic compounds. A. Phototrophs B. Heterotrophs C. Autotrophs D. Chemotrophs

B. Heterotrophs

Trypanosomiasis is a disease found in Africa and is spread by tsetse flies. The disease is caused by Trypanosoma brucei gambiense, which is a protist parasite, and it is usually fatal without treatment. The protist cannot complete its life cycle in the tsetse fly alone; it requires a human host. Humans are the main infected animal, but this pathogen can be found in cattle and pigs. The disease is mostly transmitted by tsetse flies, but can also be transmitted from a mother to an unborn baby, through sexual contact, and by blood transfusions. Based on this information, Trypanosomiasis can be classified as... A. a global pandemic B. a bacterial disease C. a disease without an animal reservoir D. an emerging infectious disease E. a chronic condition F. a vector-borne disease G. a disease with a higher Ro than an airborne disease, like the flu

B. a bacterial disease

You are most likely to observe primary succession when you visit A. an abandoned agricultural field. B. a very young volcanic island. C. a desert after a fungal pathogen kills many prickly pear cacti. D. a temperate forest after a gypsy moth outbreak. E. a burned tropical rain forest. F. an old riverbed.

B. a very young volcanic island.

Plants get the carbon that they use to form biological molecules (such as sugar) from _____ and plants get the nitrogen that they use to form biological molecules (such as proteins) from _______. A. air; air B. air; soil C. soil; air D. soil; soil

B. air; soil

Which of the following correctly describes a type of viral genome? (Choose all that apply) A. a double helix with one DNA strand and one RNA strand B. double-stranded RNA C. single-stranded DNA D. double-stranded DNA E. single-stranded RNA

B. double-stranded RNA C. single-stranded DNA D. double-stranded DNA E. single-stranded RNA

Which of the following is associated with increased emergence of new infectious diseases? A. development of sewage treatment and sanitation B. human exploration of wild areas C. discovery of antibiotics D. development of immunization

B. human exploration of wild areas

Primary producers are vital components of a food web because they: A. serve as decomposers. B. incorporate the carbon contained in atmospheric CO2 into C6H12O6. C. return carbon (as CO2) to the atmosphere. D. immediately provide tertiary consumers with usable forms of carbon. E. all of the answers are correct.

B. incorporate the carbon contained in atmospheric CO2 into C6H12O6.

The difference between primary and secondary succession is... A. primary succession happens immediately following a disturbance, and secondary succession begins 5-10 years following a disturbance. B. primary succession occurs following a disturbance that is so severe the soil has to be formed from rock and organic matter, whereas secondary succession occurs following a disturbance where the soil is left intact. C. primary succession occurs following a disturbance whereas secondary succession is always occurring. D. primary succession occurs in older biomes, like the tropics, whereas secondary succession only occurs in biomes that have recently had an ice age or other similar event. E. primary succession results in a predictable climax community, whereas the process of secondary succession includes more random events.

B. primary succession occurs following a disturbance that is so severe the soil has to be formed from rock and organic matter, whereas secondary succession occurs following a disturbance where the soil is left intact.

The term "human microbiome" refers to which of the following? A. the microbes that decompose organic matter created by humans B. the microbes that live in and on human bodies, most of which are beneficial to humans C. the microbes that live on plastics and other materials created by humans D. Archaea and Bacteria whose abundance is influenced by human activities E. disease-causing organisms that are associated with people

B. the microbes that live in and on human bodies, most of which are beneficial to humans

Clostridium difficile is a bacterium that is often found in the gastrointestinal tract of healthy individuals. It is also a common cause of hospital-acquired infections. Most individuals who become ill with C. difficile do so following antibiotic treatment. This information suggests that: A. C. difficile is not pathogenic (disease-causing) in healthy people. B. C. difficile is adapted to the human gastrointestinal tract. C. C. difficile is resistant to antibiotics and antiseptics used in the hospital setting. D. C. difficile rebels when other organisms are eliminated from their environment.

C. C. difficile is resistant to antibiotics and antiseptics used in the hospital setting.

Which of the following statements is NEITHER a pattern of biodiversity NOR an explanation of biodiversity patterns? A. Biomes in the tropics have lower extinction rates. B. As we move towards the equator biodiversity increases. C. Habitats at the poles are older. D. Different latitudes have different levels of species richness. E. Biodiversity is proportional to the area of the habitat.

C. Habitats at the poles are older.

Which of the following statements regarding the species-area relationship is correct? A. It explains why there are more amphibians in Cuba than there are in Michigan. B. It can be used to predict which species will occur in a given habitat. C. It says that the number of species on an island tends to increase with the area of the island. D. It says that the number of individuals in a populations tends to increase as the number of species on an island increases. E. All of the choices are correct statements.

C. It says that the number of species on an island tends to increase with the area of the island.

Which is true of Lyme disease? Pick the one, best answer. A. Lyme disease is a disease of conservation concern, because ticks transfer it among the mice and deer populations in deciduous forests B. Lyme disease is caused by a virus that infects bats C. Lyme disease is caused by a type of bacterium that normally lives in deciduous forest communities, but sometimes moves into human populations D. Lyme disease is caused by a eukaryotic parasite that ticks transfer from animal hosts to human hosts E. Lyme disease causes substantially high death rates in black legged tick populations

C. Lyme disease is caused by a type of bacterium that normally lives in deciduous forest communities, but sometimes moves into human populations

Which of the following statements about viruses is FALSE? A. They recognize host cells by their unique glycoproteins. B. Most are obligate parasites. C. They represent a fourth domain of life. D. They are very common. E. They are very small.

C. They represent a fourth domain of life.

How do vaccines work? A. They contain a weakened or dead version of the infectious agent, which triggers a vasovagal response (fainting) that confers lifetime immunity to the disease. B. They contain antibodies and memory cells that, once injected into a person, gives that person immunity to a particular infectious disease. C. They use a weakened or dead version of the infectious agent to trigger an immune response in a person, generating memory cells that can more quickly fight off infections in the future. D. They cause full-scale disease in a patient at a time when the patient can be monitored carefully, leading to lifetime immunity to that disease.

C. They use a weakened or dead version of the infectious agent to trigger an immune response in a person, generating memory cells that can more quickly fight off infections in the future.

Disturbances: A. affect populations differently according to the population's density. B. are extremely rare. C. can influence the diversity of species in a community. D. involve interactions such as competition and predation. E. usually only affect one particular species in a community.

C. can influence the diversity of species in a community.

Escherichia coli bacteria in your colon are best categorized as ____________. A. photoheterotrophs B. photoautotrophs C. chemoheterotrophs D. chemoautotrophs

C. chemoheterotrophs

The first law of thermodynamics states that ____________. A. energy transfers are not 100% efficient B. only eukaryotic cells can produce ATP C. energy cannot be created or destroyed

C. energy cannot be created or destroyed

Consider a community composed of grasses, prairie dogs, mice, bison and coyotes. Which of these organisms would be found at the bottom level of the trophic pyramid for this community? A. coyotes B. mice C. grasses D. prairie dogs E. bison

C. grasses

__________ convert nitrate to nitrogen gas via ____________. ___________ convert nitrogen gas to ammonium via _____________. A. microbes, nitrogen fixation; plants, denitrification B. plants, nitrogen fixation; microbes, decomposition C. microbes, denitrification; microbes, nitrogen fixation D. microbes, nitrogen fixation; microbes, decomposition E. animals, respiration; plants, nitrogen fixation

C. microbes, denitrification; microbes, nitrogen fixation

Oak trees are best categorized as ____________. A. photoheterotrophs B. chemoheterotrophs C. photoautotrophs D. chemoautotrophs

C. photoautotrophs

Which of the following organisms can incorporate atmospheric carbon directly into C6H12O6, thereby playing a major role in a food web? A. primary consumers B. herbivores C. primary producers D. secondary consumers E. decomposers

C. primary producers

Imagine that you have a garden full of sunflowers in your backyard. Unfortunately, you don't have much time to tend to the garden. You eventually notice that two small birch trees sprout and begin to grow among the sunflowers. The birch trees are slower growers than the sunflowers, but by the fifth summer they start to shade the sunflowers. The progression of your garden from sunflowers to birch trees is an example of: A. competition. B. evolution. C. succession. D. None of the responses is correct. E. ecology.

C. succession.

Viral diseases of humans are difficult to treat with drugs because.... A. we cannot make chemicals to attack viral replication, transcription, and translation enzymes because they are so different from the eukaryotic enzymes. B. viral particles spontaneously self-assemble and cannot be stopped by any pharmaceuticals. C. viral replication primarily involves human enzymes so it is difficult to make a non-toxic drug that blocks viral replication. D. viruses are too small to be acted upon by drugs. E. All of the choices are correct.

C. viral replication primarily involves human enzymes so it is difficult to make a non-toxic drug that blocks viral replication.

The latitudinal diversity gradient refers to what pattern of species diversity? A. For many kinds of organisms, species diversity is greatest at low elevation and lowest at high elevation. B. Plants are most diverse near the equator while animals are most diverse toward the poles. C. For many kinds of organisms, species diversity is greatest at high elevation and lowest at low elevation. D. For many kinds of organisms, species diversity is greatest near the equator and lowest near the poles. E. For many kinds of organisms, species diversity is greatest near the poles and lowest near the equator.

D. For many kinds of organisms, species diversity is greatest near the equator and lowest near the poles.

One reason why HIV is so difficult to effectively treat is that... A. Every HIV virus particle presents a series of novel antigens (a substance that provokes an immune system response), wearing out the host's immune system. B. Scientists have not been able to determine where the HIV virus originated. C. HIV responds to immune system attack by increasing its replication rate and mutation rate. D. HIV has a high mutation rate, which results in many different virus variants in an infected person's body. E. T cells cannot easily bind to HIV virus particles because the HIV capsid is irregularly shaped.

D. HIV has a high mutation rate, which results in many different virus variants in an infected person's body.

A technique called "Slash-and-Burn" is used to clear-cut and burn forests to quickly turn them into agricultural fields. Which plant trait would LEAST aid colonization during the early succession of these fields? A. Good seed dispersal ability B. Enhanced ability to acquire nutrients C. Efficient water use D. High shade tolerance E. Ability to grow in disturbed soils

D. High shade tolerance

David Tilman's experiments in Minnesota were designed to test which of the following hypotheses? A. Biodiversity decreases the number of weed species found in prairie ecosystems. B. Decreased carbon dioxide increases productivity in prairie ecosystems. C. Extinction rates increase with increased species richness. D. Primary productivity increases with increasing species richness. E. The presence of top predators increases biodiversity in prairie ecosystems.

D. Primary productivity increases with increasing species richness.

Why do fecal transplants work? A. Because they ensure that the donor recently took antibiotics, and, therefore, that the donor does not contain any disease-causing bacteria in his/her gut. B. Because they first clear the recipient's gut flora using clindamycin, an antibiotic. C. Because there is no other alternative to treating Clostridium difficile infections. D. They transplant a healthy gut community into the affected individual, restoring the diversity of the gut flora. E. none of the choices are correct

D. They transplant a healthy gut community into the affected individual, restoring the diversity of the gut flora.

A disease that has always infected people in one region increases substantially in prevalence in that geographic region. The disease does not spread to any other geographic regions. This describes: A. a zoonosis B. a pandemic C. an endemic disease D. a disease epidemic

D. a disease epidemic

A disease that has always infected people in one geographic region increases substantially in prevalence and now infects people on five continents. This describes: A. an endemic disease B. a zoonosis C. a disease epidemic D. a pandemic

D. a pandemic

Which of the following is NOT associated with increased emergence of new infectious diseases? A. increased global travel B. wars C. increased human population size D. improved hygiene, such as frequent hand washing E. human exploration of wild areas F. natural disasters

D. improved hygiene, such as frequent hand washing

If the net primary productivity of a system is 367.4 g C/m2/yr, and respiration is 111.3 g C/m2/yr, what is the gross primary productivity of this system? A. it is not possible to determine given the available information B. 256.1 g C/ m2/yr C. 3.3 g C/ m2/ yr D. 423.05 g C/ m2/yr E. 478.7 g C/ m2/yr F. 311.75 g C/ m2/yr

E. 478.7 g C/ m2/yr

What is true of an "indirect interaction" in community ecology? Note that the organisms in this question refer to those in the "Of Mice and Mast" article that you read for prediscussion. A. The increase in tick prevalence with oak tree mast is an example of an indirect interaction. B. An indirect interaction is when a species (A) affects another species (B), and that species (B) affects another species (C), such that species A affects species C through the B-C relationship. C. The positive correlation between tick prevalence and oak tree mast is an example of an indirect interaction. D. The increase in Lyme disease risk to humans following an oak mast is an example of an indirect interaction. E. All of these choices are true of an "indirect interaction" in community ecology.

E. All of these choices are true of an "indirect interaction" in community ecology.

Dengue Fever is a disease caused by 4 strains of a virus called a Flavivirus. It has no non-human animal reservoirs, but it is transmitted by tropical mosquito species. Infection by more than one strain of the virus can lead to Dengue hemorrhagic fever, which is often fatal. The number of cases has increased in the past 10 years. Increasing global temperatures have increased the range of many tropical species of mosquito that can carry and transmit the virus, and there are several instances of the virus being transported worldwide in infected mosquitoes in shipping containers, full of fruit destined for grocery stores, etc. Based on this information, would you classify Dengue Fever as an EID? A. No, because there are no non-human animal reservoirs for Dengue Fever. B. Yes, because EIDs are often fatal and usually have animal vectors, like mosquitos or biting flies. C. No, because mosquito vectors are likely to go extinct due to climate change within the next 30 years. D. No, because the description does not indicate that this disease is a zoonosis. E. Yes, because its prevalence has increased in the past 10 years and climate change will likely further increase the range of tropical mosquitoes, likely increasing the incidence of Dengue Fever in the future.

E. Yes, because its prevalence has increased in the past 10 years and climate change will likely further increase the range of tropical mosquitoes, likely increasing the incidence of Dengue Fever in the future.

Which of the following things result from symbiotic relationships between bacteria and eukaryotes? (Select all correct choices.) A. cellulose breakdown in the human gut B. vitamin production in the human gut C. amino acid synthesis in aphids D. bioluminescence in the bobtail squid E. all of the above

E. all of the above

Which of the following is the most common group of organisms that transmits vector-borne diseases between people? A. crustaceans B. nematodes C. leeches D. bats E. arthropods F. mice

E. arthropods

Which of the following organisms would most likely be first to colonize an area undergoing succession? A. small mammals B. oak trees C. insects D. large mammals E. mosses

E. mosses

You are hiking within the northern hardwood forest region of the upper peninsula of Michigan and you pass through two small woodlands. Because we have turned you into a biology enthusiast, you count and identify all the trees that you pass. In woodland A, you find 50 sugar maple trees, 50 yellow birch trees, and 50 red oak trees. In woodland B, you find 100 sugar maple trees, 48 yellow birch trees and 2 red oak trees. The most accurate comparison of these woodlands would be that A. they differ in both tree species richness and diversity. B. they have equal tree species diversity. C. they differ in insect species richness. D. they differ in primary productivity. E. they have equal tree species richness.

E. they have equal tree species richness.

Earth's air is a reservoir of nitrogen (that is, there is a lot of nitrogen in the air). However, plants cannot use the nitrogen in the air. How can atmospheric nitrogen be converted into a form of nitrogen that is usable by plants? What form of nitrogen is used by the plants? A. Nitrogen fixation by industry forms nitrate. B. Nitrogen fixation by bacteria forms ammonia, followed by nitrification by bacteria and/or archaea which forms nitrate. C. Nitrogen fixation by industry forms ammonia. D. Nitrogen fixation by archaea forms ammonia, followed by nitrification by bacteria and/or archaea which forms nitrate. E. Rhizobium bacteria in root nodules fix nitrogen into a usable form such as ammonia. F. All of these are reasonable ways in which nitrogen is converted into a form that is usable by plants, and the form is accurate.

F. All of these are reasonable ways in which nitrogen is converted into a form that is usable by plants, and the form is accurate.

In the Ostfeld, et al. article, "Of Mice and Mast," which of the following is a valid interpretation of figure 1 (page 324)? (Hint: Read the caption carefully.) A. The article presents data which support every arrow in this figure. B. "Mast production" refers to the huge increase in population of the mice, ticks, and deer, which are the second level of this food web. C. The figure indicates that humans eat deer and acorns, but not ticks. D. Every arrow moves from the prey to the predator OR from the plant to the herbivore. E. The shadowed boxes indicate an indirect interaction, while the unshadowed boxes indicate a direct interaction. F. Plus symbols (+) can indicate either an increase in biomass OR an increase in density, which could be caused by behavioral changes & migration OR changes in reproductive fitness.

F. Plus symbols (+) can indicate either an increase in biomass OR an increase in density, which could be caused by behavioral changes & migration OR changes in reproductive fitness.

True or False. AIDS is no longer a serious health threat in the United States.

False

True or False. The invention of immunizations had no effect on decreasing human deaths due to infectious diseases.

False

True or False: A pride of lions moves into a new area of the savanna that was previously a refuge for zebras. Lions begin killing zebras for food and the zebra population decreases. This is an example of an ecological disturbance.

False

True or False: As you travel from 90 degrees north latitude south to the equator, you would expect species richness to decrease.

False

True or false: to be considered "emerging", a disease needs to increase by at least 10% in 10 years.

False

You have been put in charge of developing a vaccination strategy for pertussis (aka whooping cough), which is emerging on some college campuses. What percent of students would need to be vaccinated in order for herd immunity to be effective? The Ro for pertussis is 18. Assume all vaccinations are effective. A. 90% B. 75% C. 10% D. 100% E. 5% F. 50% G. 95% H. 25%

G. 95%

Which of the following is/are disturbances? Choose all that apply. A. Road Building B. Hurricanes C. Earthquakes D. Volcanic eruptions E. Agriculture F. Droughts G. Fires H. All of the above

H. All of the above

Ostfeld et al. state that the "...focus of community ecology has been on pairwise interactions between species..." Which of the following is NOT a TYPE of pairwise interaction or an EXAMPLE of a pairwise interaction? A. The interaction between white-footed mice and the Lyme disease bacteria (Borrelia burgorferi) B. The interaction between ticks and deer C. The interaction between oak trees and white- footed mice D. The interaction between oak trees and deer E. The interaction between ticks and white-footed mice F. Predation G. Parasitism H. The interaction between oak trees and the Lyme disease bacteria (Borrelia burgdorferi) I. The interaction between ticks and humans

H. The interaction between oak trees and the Lyme disease bacteria (Borrelia burgdorferi)

True or False: "Disease" is the term used for the physical symptoms caused by a parasite or pathogen.

True

True or False: No matter where it is located, a large geographic area will have a higher species richness than a small geographic area.

True

True or False: There are more bacteria in/on humans than there are cells within the human organism.

True