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Total Categories: 7
In an ecological context, biomass is defined as the total mass of living organisms within a specific location at a given moment, encompassing both organic and inorganic matter.
Answer: False
Ecological biomass specifically refers to the total mass of *living* organisms. The inclusion of inorganic matter is not part of the standard definition.
Total global net primary production refers to the total standing biomass of living organisms on Earth.
Answer: False
Total global net primary production quantifies the rate at which new biomass is generated annually across the planet, rather than the total standing biomass at a given moment.
What is the ecological definition of biomass?
Answer: The total mass of living biological organisms within a specific area or ecosystem at a particular point in time.
In ecology, biomass refers to the total mass of living biological organisms within a specific area or ecosystem at a particular point in time.
Which of the following is NOT a way biomass can be measured or expressed, according to the text?
Answer: Total weight including all inorganic skeletal structures.
Biomass is typically measured as wet weight, dry organic mass, or carbon mass. Including inorganic skeletal structures is not a standard method for quantifying ecological biomass.
What does 'total global net primary production' measure?
Answer: The rate at which new biomass is generated globally per year.
Total global net primary production quantifies the rate at which new biomass is generated annually across the planet by autotrophs.
Earth's total live biomass was estimated to be approximately 550 billion tonnes of carbon in a 2018 study, with plants making up the largest share.
Answer: True
A 2018 study estimated Earth's total live biomass at approximately 550 billion tonnes of carbon, with plants constituting the predominant share.
The total biomass of animals on Earth represents a substantial fraction, exceeding 10%, of the planet's total live biomass.
Answer: False
Animals constitute a relatively small fraction of Earth's total biomass, representing less than 0.5%, with a total estimated biomass of about 2 billion tonnes of carbon.
The majority of Earth's total biomass is found in animals and fungi.
Answer: False
Plants constitute the majority of Earth's total biomass, estimated at 450 billion tonnes of carbon, far exceeding the biomass of animals (approx. 2 billion tonnes C) and fungi (approx. 12 billion tonnes C).
The total DNA base pairs on Earth have an approximate mass significantly less than the total biomass of plants.
Answer: False
The estimated mass of all DNA base pairs on Earth is approximately 50 billion tonnes, whereas the total biomass of plants is estimated at 450 billion tonnes of carbon, indicating plant biomass is considerably greater.
According to a 2018 study, what constitutes the vast majority of Earth's estimated 550 billion tonnes of carbon biomass?
Answer: Plants
The 2018 study indicated that plants represent the vast majority of Earth's estimated 550 billion tonnes of carbon biomass.
What percentage of Earth's total biomass is represented by animals?
Answer: Less than 0.5%
Animals constitute less than 0.5% of Earth's total biomass, with an estimated total biomass of approximately 2 billion tonnes of carbon.
In terrestrial ecosystems, biomass typically increases significantly at each successive trophic level, forming an inverted pyramid structure.
Answer: False
Terrestrial ecosystems typically exhibit upright biomass pyramids, where biomass decreases significantly at each successive trophic level, with producers at the base.
Marine ecosystems can sometimes exhibit inverted biomass pyramids, where consumer biomass exceeds producer biomass.
Answer: True
Unlike most terrestrial ecosystems, marine environments can display inverted biomass pyramids, wherein the biomass of consumers may surpass that of the primary producers.
An ecological pyramid exclusively represents the amount of biomass present at each trophic level.
Answer: False
Ecological pyramids can represent various ecological metrics, including biomass, numbers of organisms, or energy transfer rates at each trophic level, not exclusively biomass.
Productivity pyramids are generally not inverted because energy transfer between trophic levels is highly efficient, allowing higher levels to accumulate more biomass.
Answer: False
Productivity pyramids are generally not inverted because energy transfer between trophic levels is inefficient (approximately 90% loss), preventing higher levels from accumulating more biomass than lower levels based on production rates.
How does the biomass pyramid typically differ between terrestrial and marine ecosystems?
Answer: Terrestrial pyramids are typically upright, while marine pyramids can be inverted.
Terrestrial ecosystems generally exhibit upright biomass pyramids, whereas marine ecosystems frequently display inverted biomass pyramids where consumer biomass exceeds producer biomass.
What does a biomass pyramid represent in an ecological context?
Answer: The total amount of biomass present at each trophic level.
A biomass pyramid graphically illustrates the total mass of living organisms present at each successive trophic level within an ecosystem.
Why are productivity pyramids generally not inverted?
Answer: The 10% energy transfer rule ensures lower levels produce more biomass over time.
Productivity pyramids are typically not inverted due to the inefficient transfer of energy (approximately 10%) between trophic levels, which limits the biomass that can be accumulated at higher levels.
*Prochlorococcus* is a large multicellular organism significant for its role in terrestrial ecosystems.
Answer: False
*Prochlorococcus* is a marine cyanobacterium, significant for its abundance and role in oceanic ecosystems, not terrestrial ones.
The biomass of fish in the world's oceans is estimated to be higher than the biomass of all terrestrial plants.
Answer: False
The biomass of terrestrial plants is estimated at 450 billion tonnes of carbon, significantly exceeding the estimated biomass of fish in the oceans, which is around 0.7 billion tonnes of carbon.
Mesopelagic fish, inhabiting deep ocean waters, constitute a significant portion of the total fish biomass in the oceans.
Answer: True
Mesopelagic fish, found in deep ocean waters, represent approximately half of the total fish biomass in the world's oceans.
Satellite data, using NDVI and sea-surface chlorophyll levels, is used to estimate global primary production.
Answer: True
Satellite remote sensing estimates global primary production by analyzing Normalized Difference Vegetation Index (NDVI) for terrestrial areas and chlorophyll concentrations for oceanic regions.
Oceanic primary producers like phytoplankton have a large standing biomass but a slow turnover rate.
Answer: False
Oceanic primary producers, such as phytoplankton, exhibit a small standing biomass but a rapid turnover rate, enabling them to contribute significantly to global primary production.
The biomass of blue whales has increased significantly since the era of widespread whaling.
Answer: False
The biomass of blue whales has decreased substantially from an estimated 36 million tonnes before widespread whaling to around 3 million tonnes currently.
Antarctic krill have a biomass comparable to that of marine mammals.
Answer: False
Antarctic krill have an estimated biomass of approximately 379 million tonnes, which is considerably larger than the estimated biomass of marine mammals (around 0.006 billion tonnes of carbon).
Copepods and cyanobacteria (*Prochlorococcus*) have similar estimated biomass levels in the oceans.
Answer: True
Both copepods and cyanobacteria, such as *Prochlorococcus*, are estimated to have biomass levels around 1,000 million tonnes in the oceans, indicating their significant ecological roles.
Tropical rainforests and coral reefs have similar high biomass productivity rates.
Answer: True
Both tropical rainforests and coral reefs exhibit high biomass productivity rates, estimated at 2,000 grams of carbon per square meter per year.
What organism forms the base of most marine food chains and is a primary producer?
Answer: Phytoplankton
Phytoplankton, microscopic marine algae, are the primary producers forming the base of most marine food chains.
Which of the following is a type of zooplankton mentioned as playing a significant role in marine food webs?
Answer: Both B and C
Copepods and Antarctic krill are both types of zooplankton that play significant roles in marine food webs.
What is *Prochlorococcus*?
Answer: A marine cyanobacterium, significant for its abundance and role in oxygen production.
*Prochlorococcus* is a marine cyanobacterium, recognized as one of the most abundant organisms on Earth and a significant contributor to oceanic oxygen production and the marine food chain.
What is the estimated biomass of fish in the world's oceans?
Answer: 0.7 billion tonnes of carbon
The estimated biomass of fish inhabiting the world's oceans is approximately 0.7 billion tonnes of carbon.
Which type of fish constitutes roughly half of the total fish biomass in the oceans?
Answer: Mesopelagic fish
Mesopelagic fish, dwelling in the ocean's twilight zone, constitute approximately half of the total fish biomass found globally.
How is global primary production estimated using satellite data?
Answer: By scanning NDVI over land and chlorophyll levels over oceans.
Satellite remote sensing estimates global primary production by analyzing Normalized Difference Vegetation Index (NDVI) for terrestrial areas and chlorophyll concentrations for oceanic regions.
Compared to terrestrial ecosystems, oceanic primary producers generally have:
Answer: A smaller standing biomass and a faster turnover rate.
Oceanic primary producers, like phytoplankton, typically possess a smaller standing biomass but exhibit a faster turnover rate compared to terrestrial producers.
What is the estimated biomass of Antarctic krill?
Answer: Around 379 million tonnes
The estimated biomass of Antarctic krill is substantial, reaching approximately 379 million tonnes during peak seasons.
Which group has a similar estimated biomass in the oceans as copepods?
Answer: Cyanobacteria (like *Prochlorococcus*)
Copepods and cyanobacteria, such as *Prochlorococcus*, are estimated to have similar biomass levels in the oceans, both around 1,000 million tonnes.
What was the approximate biomass of blue whales before widespread whaling began?
Answer: 36 million tonnes
Before the era of widespread whaling, the estimated biomass of blue whales was approximately 36 million tonnes.
Which of these ecosystems has a biomass productivity rate significantly lower than the open ocean?
Answer: Deserts
Deserts have extremely low biomass productivity rates (approx. 3 g C/m²/yr), significantly lower than the open ocean (approx. 125 g C/m²/yr).
In terrestrial ecosystems, phytoplankton are the primary producers at the base of most food chains.
Answer: False
Phytoplankton are primary producers in marine ecosystems. In terrestrial ecosystems, plants form the base of most food chains and represent the largest share of biomass.
Swamps and marshes have lower biomass productivity rates than deserts.
Answer: False
Swamps and marshes exhibit significantly higher biomass productivity rates (e.g., 2,500 g C/m²/yr) compared to deserts (e.g., 3 g C/m²/yr).
The biomass of ants on Earth is negligible compared to that of wild mammals.
Answer: False
The biomass of ants is substantial, estimated between 10 to 100 million tonnes of dry weight, comparable to or exceeding the biomass of wild mammals.
Earthworms have a greater global biomass than nematodes.
Answer: True
The global biomass of earthworms is estimated at around 400 million tonnes of dry weight, significantly greater than the estimated biomass of nematodes, which is around 60 million tonnes of dry weight.
According to the text, what proportion of the total animal biomass on Earth is found on land?
Answer: About 20%
Land animals account for approximately 500 million tonnes of carbon, which represents about 20% of the total animal biomass on Earth.
Which ecosystem type exhibits the highest biomass productivity rates?
Answer: Swamps and marshes
Swamps and marshes demonstrate the highest biomass productivity rates among ecosystems, followed closely by tropical rainforests and coral reefs.
The biomass of fungi on Earth is estimated to be significantly larger than the biomass of all animals combined.
Answer: True
Fungi have an estimated global biomass of 12 billion tonnes of carbon, which is considerably larger than the estimated total biomass of all animals, approximately 2 billion tonnes of carbon.
Initial estimates of prokaryotic biomass in deep subseafloor sediments were much lower than later, updated measurements.
Answer: False
Initial estimates of prokaryotic biomass in deep subseafloor sediments (around 300 billion tonnes C) were substantially higher than subsequent updated measurements (around 4 billion tonnes C).
The biomass of Protista is greater than the combined biomass of bacteria and archaea.
Answer: False
The combined biomass of bacteria and archaea is estimated at 30 billion tonnes of carbon, whereas Protista biomass is estimated at 4 billion tonnes of carbon.
What is the estimated global biomass of fungi in tonnes of carbon?
Answer: 12 billion tonnes
The global biomass of fungi is estimated to be approximately 12 billion tonnes of carbon.
How did updated measurements of prokaryotic biomass in deep subseafloor sediments compare to initial estimates?
Answer: Updated estimates were significantly lower.
Updated measurements of prokaryotic biomass in deep subseafloor sediments revealed significantly lower estimates compared to initial assessments.
Humans and their domesticated livestock account for the vast majority of the total biomass of mammals on Earth.
Answer: True
Studies indicate that humans and their domesticated livestock collectively constitute approximately 96% of the total biomass of mammals on Earth.
Technomass refers to the total biomass of all living organisms on Earth.
Answer: False
Technomass refers to the total mass of human-made materials, distinct from the biomass of living organisms.
By the year 2020, the mass of human-made materials (technomass) was projected to exceed the combined mass of all land and marine animals.
Answer: True
A projection indicated that by 2020, the mass of human-made materials (technomass), particularly plastics, was expected to surpass the combined biomass of all land and marine animals.
The biomass of wild terrestrial mammals significantly exceeds that of humans and their domesticated livestock.
Answer: False
Humans and their domesticated livestock account for approximately 96% of the total mammal biomass on Earth, far exceeding the biomass of wild terrestrial mammals.
What striking finding does the text present regarding the biomass distribution of mammals?
Answer: Humans and their livestock make up 96% of total mammal biomass.
A notable finding is that humans and their domesticated livestock comprise 96% of the total mammal biomass on Earth, with wild mammals representing only the remaining 4%.
Which of the following has a greater estimated global biomass?
Answer: Humans
Humans have a greater estimated global biomass (approx. 80 million tonnes C) than wild terrestrial mammals (approx. 3 million tonnes C) and ants (estimated 10-100 million tonnes dry weight, which is less than human carbon biomass).