Biology Chapter 3: Ecology Study Guide

How does most of the carbon in an organism's body return to the environment after the organism dies?

decomposers break the body down into simpler compounds.

What is the significance of carbon to living things?

it is a key ingredient in the macromolecules of life.

How does matter move through the biosphere?

it is recycled.

Which parts of the phosphorus cycle are geological processes?

phosphorus is stored in rocks and ocean sediments and later is gradually released into water and soil.

T or F, energy can be created and destroyed.

False, energy can be created but cannot be destroyed.

What is a food web? What is a food chain?

Food Web: network of feeding interactions. Food Chain: series of steps that transfer energy by animals eating others or being eaten.

Explain the 10% rule.

Typically only 10% of the energy available within one trophic level is stored in the next trophic level.

What is a trophic level?

a step in a food chain or web.

What is a biotic factor?

biological (living) influences on an organism. ex: animals, bacteria, fungi, and plants.

List and briefly explain the diet of the six consumer classifications we discussed in class.

carnivores: eat meat herbivores: eat plants omnivores: eat meat and plants detritivores: eat soil and detritus decomposers: eat trees and bacteria scavengers: eat dead animals

How do primary producers capture energy?

from the sun and soil.

How does energy move through the biosphere?

in a one-way flow.

What are some reasons why only 10% of the energy in a trophic level is passed on to the next trophic level?

most of the energy is used for digestion and breathing, so when the animal gets eaten there is not a lot to pass on to the next.

What is the significance of nitrogen to living things?

needed by all organisms to build proteins.

What is the significance of phosphorus to living things?

needed to make molecules like DNA and RNA.

What is an abiotic factor?

physical (nonliving) influences on an organism. ex: sunlight, temperatures, wind, soil type, and water currents.

List some examples of primary producers.

plants and lichen

List and briefly explain the levels of ecological organization.

species: a group of similar organisms that can breed and reproduce fertile offspring. population: a group of species in the same area. community: assemblage of different populations living in a defined area ecosystem: all of the organisms that live in a place along with the physical environment. biome: a group of ecosystems that share similar climates and typical organisms. biosphere: all life on earth and parts of earth where life exists.

How do humans add nitrogen to the biosphere?

the use and manufacturing of fertilizers.

T or F, matter cannot be created or destroyed.

true.