Biodiversity & Stability
What are the three types of biodiversity?
Genetic, species, and ecosystem/ecological diversity.
What two abiotic factors are most important for determining a terrestrial biome?
Temperature and precipitation.
What is the difference between habitat destruction and habitat fragmentation?
Destruction removes habitat; fragmentation divides continuous habitat into smaller isolated pieces.
What is the difference between a biotic and an abiotic factor?
Biotic = living/once-living; abiotic = nonliving environmental factor.
What is the role of a producer in an ecosystem?
Producers capture energy and make energy-rich organic molecules, forming the base of the food web.
What does it mean for an ecosystem to be resilient?
The ability of an ecosystem to recover from or adjust to change/disturbance.
Which terrestrial biome has permafrost, low precipitation, and a very short growing season?
Tundra
very short growing season?What is an invasive species, and why can it threaten native biodiversity?
A nonnative species that spreads and causes harm, often by competing with, consuming, or otherwise disrupting native species.
What is the difference between an open system and a closed system?
Open systems exchange matter and energy with their surroundings; closed systems exchange energy but little/no matter.
What do the arrows in a food web represent, and which direction do they point?
Arrows show the direction of energy transfer, pointing from the organism being eaten toward the organism that eats it.
How does having many species with different niches help increase ecosystem stability?
Different niches allow species to use resources differently and perform different ecological roles,
A climograph shows high temperatures and high precipitation throughout the entire year. Which biome does it most likely represent?
Tropical Rainforest
A highway divides one large forest into several smaller sections. What threat to biodiversity does this represent, and why can it be harmful?
Habitat fragmentation; populations can become isolated and have reduced access to resources, mates, or migration routes.
Explain the difference between a positive feedback loop and a negative feedback loop
Positive feedback amplifies change; negative feedback counteracts change and promotes stability.
A rabbit eats grass and is then eaten by a fox. Identify the producer, primary consumer, and secondary consumer.
Grass = producer; rabbit = primary consumer; fox = secondary consumer.
Two forests experience the same disease outbreak. Forest A contains many different tree species, while Forest B contains mostly one tree species. Which forest would likely be more resilient, and why?
Forest A because greater species diversity makes it less likely that one disease will severely affect the entire forest.
Two locations receive similar amounts of precipitation, but one is much colder throughout the year. Explain why the two locations could still have different terrestrial biomes.
Temperature affects growing season, available water, and which organisms can survive, so similar precipitation does not necessarily produce the same biome.
A nonnative insect kills large numbers of trees in a forest. Explain two ways this could affect biodiversity within the ecosystem.
Possible effects include habitat loss, reduced food/resources, population declines, disrupted food webs, or loss of species diversity.
How does the Second Law of Thermodynamics help explain why energy transfer through an ecosystem is inefficient?
Some usable energy is transformed and dispersed as thermal energy during each energy transfer, leaving less available to the next trophic level.
If producers contain 10,000 units of energy, approximately how much energy would be available to secondary consumers according to the 10% rule?
100 units. Producers 10,000 → primary consumers 1,000 → secondary consumers 100.
An ecosystem loses several species that perform similar ecological roles. It appears stable at first, but later becomes less resilient to environmental change. Explain why the loss of biodiversity can eventually reduce ecosystem stability.
Fewer species/ecological roles means fewer alternative pathways for the ecosystem to maintain its functions when disturbances occur.
A region becomes warmer and drier over several decades. Predict how its terrestrial biome could change and explain how those changing abiotic conditions could affect its biotic factors.
connect warmer/drier conditions to a shift toward a drier biome and explain resulting changes in organisms.
A large forest is cleared for development, leaving several small isolated patches of habitat. Explain how both habitat destruction and habitat fragmentation are occurring and predict one effect on biodiversity.
Development destroys part of the habitat while also dividing the remaining habitat into isolated patches; both can reduce biodiversity.
Arctic sea ice melts, exposing darker ocean water. The darker water absorbs more solar energy, causing additional warming and even more ice to melt. Identify the type of feedback loop and explain your reasoning.
Positive feedback because the initial warming causes changes that lead to additional warming.
A disease causes a major decline in a primary consumer population. Predict how this could affect both the producers and secondary consumers in the food web, and explain why.
Producers would likely increase because fewer primary consumers are eating them, while secondary consumers that depend on those primary consumers could decrease because less food is available.