assesment bio

Carbon Cycle

Continuous exchange of carbon among the atmosphere, oceans, land, and organisms through photosynthesis, respiration, decomposition, and combustion.

Nitrogen Cycle

Converts nitrogen into multiple forms circulating through the atmosphere, land, and sea. Key processes: nitrogen fixation, nitrification, etc.

Phosphorus Cycle

Movement of phosphorus through the earth. Slow cycle; phosphorus is typically in rocks. Weathering releases it into the soil for plants.

10% Rule

Only about 10% of energy is transferred to the next trophic level, limiting food chain length due to energy loss as heat.

Food Webs: Role of Each Organism

Interconnected food chains where producers (autotrophs) are eaten by consumers (heterotrophs like herbivores, carnivores, and omnivores).

Autotrophs vs. Heterotrophs

Autotrophs produce their own food; heterotrophs consume other organisms for energy and nutrients.

Keystone Species

Species crucial to an ecosystem's structure and stability; its removal drastically changes the ecosystem.

Population Growth (Exponential/Logistic Graphs)

Exponential growth: rapid, unconstrained. Logistic growth: slows near carrying capacity, forming an S-shaped curve.

Carrying Capacity

Maximum population size an environment can sustain, limited by resources; represented as K.

Density-Dependent and Independent Factors

Density-dependent factors affect growth based on population density