Biology - 9th grade Ecology food webs etc

Ecology

What is a producer?

A producer makes its own food, primarily plants and algae.

What is a primary consumer?

A primary consumer is a herbivore that eats producers.

What is a secondary consumer?

A secondary consumer eats herbivores.

What is a tertiary consumer?

A tertiary consumer eats secondary consumers.

What are the steps in the nitrogen cycle?

Definition: 1. Nitrogen fixation → nitrogen gas → ammonium

2. Nitrification → ammonium → nitrites/nitrates

3. Denitrification → releases nitrogen gas back into the air.

What occurs in the carbon cycle?

Photosynthesis removes CO₂ from the air, respiration releases CO₂, and decomposition releases CO₂.

What is mutualism?

A relationship where both organisms benefit (e.g., bees and flowers).

What is commensalism?

A relationship where one organism benefits and the other is unaffected (e.g., remora fish and shark).

What is parasitism?

A relationship where one organism benefits and the other is harmed (e.g., tick and dog).

What do arrows in food webs indicate?

They show 'who is eaten by whom' or the direction of energy transfer.

When does the population graph become flat?

When the number dying equals the number produced, indicating a stationary phase.

How do you identify population doubling?

Compare how long it took for the population to double between points.