Biomes and Organization
What two factors determine a biome?
Temperature and Precipitation
What do the arrows in a food chain represent?
The flow of energy from one organism to another.
What process describes how water moves through evaporation, condensation, and precipitation?
The water cycle.
What happens during exponential growth?
Population increases rapidly when resources are unlimited.
What is an age structure diagram?
A graph showing the number of people in different age groups in a population.
What is the difference between tropical and temperate biomes?
Tropical biomes are warm year-round, while temperate biomes have distinct seasons.
Where does all energy in an ecosystem originally come from?
The Sun.
What process moves nitrogen between the atmosphere, soil, and living things?
The nitrogen cycle.
What type of growth occurs when population growth slows and levels off?
Logistic growth.
What are the three stages of demographic transition? Use the Birth and Death Rates to describe them
Stage 1: High birth & death rates; Stage 2: Death rate drops, birth rate stays high; Stage 3: Birth rate drops, stabilizing population.
What clues tell you that something is a desert biome?
Very little rainfall, extreme temperatures, and sparse vegetation.
What percentage of energy moves from one trophic level to the next?
10% (Rule of 10).
What process moves phosphorus through rocks, soil, and water?
The phosphorus cycle.
Name two density-dependent limiting factors.
Competition, predation, disease, or parasitism.
How can you tell if a population is growing from its age structure diagram?
If there are more young people than older people (wide base).
What are biotic and abiotic factors?
Biotic = living parts of an ecosystem; Abiotic = nonliving factors like sunlight, water, and soil.
Where does 99.9% of all energy eventually end up?
As heat lost to the environment.
How do human activities impact all of these cycles?
Through pollution, burning fossil fuels, deforestation, and fertilizer use that add or remove nutrients.
Name two density-independent limiting factors.
Natural disasters, temperature, weather events, or human activities.
What are two things used to determine if a population will grow or shrink?
Birth rate and death rate (and sometimes immigration and emigration).
What are the levels of organization in ecology, from smallest to largest?
Species → Population → Community → Ecosystem → Biome → Biosphere
What function do bacteria perform in an ecosystem?
They decompose dead matter and recycle nutrients back into the environment.
What is the difference between how matter and energy move in an ecosystem?
Matter cycles through ecosystems; energy flows in one direction and is not recycled.
What are the three main types of symbiotic relationships, and what do they mean?
Mutualism (both benefit), Commensalism (one benefits, one unaffected), Parasitism (one benefits, one harmed).
How has the human population size changed over time?
It has grown exponentially, especially since the Industrial Revolution.