life on earth - summary

• What is biodiversity?

  The variety of different organisms in an ecosystem
• What is an ecosystem composed of?

  A habitat and the community together
• What is a habitat?

  The place where an organism lives
• What is a community in ecological terms?

  All the organisms present in an area
• What defines a population?

  A group of organisms of the same species
• What is a species?

  A group of organisms that can breed to produce fertile offspring
• Give an example of an ecosystem, habitat, community, population, and species.

  Ecosystem = forest, Habitat = tree, Community = squirrels, deer, fox, Population = fox, Species = deer
• What is a pitfall trap used for?

  Sampling organisms in the soil

  
• How is a pitfall trap set up?

  A hole is dug and a cup is placed level with the soil
• Why is the top of the pitfall trap covered?

  To prevent birds from eating trapped organisms
• Why are several traps set in a study?

  To increase reliability of the results
• Why are traps checked regularly?

  To prevent animals from eating each other
• What does a quadrat sample?

  The abundance of plants in an area
• How is a quadrat used in sampling?

  A quadrat is thrown randomly and counted for plants
• What is the rule for counting plants in a quadrat?

  To ensure consistency in what is counted as "IN"
• Why is a quadrat thrown at random?

  To get a representative result of the area
• What are keys used for in ecology?

  To identify organisms
• What are biotic factors?

  Living factors that affect distribution of organisms
• What is predation?

  Predators eat prey
• What are some examples of biotic factors?

  Predation, disease, food availability, grazing, competition
• What is interspecific competition?

  Competition between different species for resources
• What is intraspecific competition?

  Competition between members of the same species
• What are abiotic factors?

  Non-living factors that affect distribution of organisms
• How is light intensity measured?

  Using a light meter without casting a shadow
• How is moisture content measured?

  Using a moisture meter and wiping the probe
• How is pH measured?

  Using a pH meter and waiting for stabilization
• How is temperature measured in soil?

  Using a thermometer inserted into the ground
• What is a line transect used for?

  To take readings across an area for distribution
• What is an indicator species?

  Indicates the level of pollution in an area
• What is photosynthesis?

  A process where plants make their own food
• What are the two stages of photosynthesis?

  Light reactions and carbon fixation
• What happens during the light reactions of photosynthesis?

  Light is trapped, water splits, and ATP is made
• What is produced as a by-product of light reactions?

  Oxygen diffuses out of the leaf
• What is the role of hydrogen in photosynthesis?

  Combines with carbon dioxide to make glucose
• What is the function of ATP in photosynthesis?

  Provides energy for the carbon fixation stage
• What can glucose produced in photosynthesis be used for?

  Energy in respiration, stored as starch, built into cellulose
• What are limiting factors in photosynthesis?

  Factors affecting the rate of photosynthesis
• What are the limiting factors of photosynthesis?

  Light intensity, carbon dioxide concentration, temperature
• What is a producer in an ecosystem?

  An organism that makes its own food
• What is a consumer?

  An organism that eats other organisms for energy