Responses to Changes in the environment

• Organisms may exist as members of a population; populations interact with other populations in a community; and communities together with the physical environment form ecosystems.
• differentiate between ecosystems, communities, populations, and organisms.

• Changes that affect organisms over time may be daily, seasonal, or long term.
• classify the various types of changes as long term, short term, or seasonal.
• Plants may respond to light by growing toward it or away from it, a behavior known as phototropism.



• Animals may respond to cold conditions with a period of lowered metabolism, a behavior known as hibernation.



• Organisms may respond to adverse conditions with a period of lowered or suspended metabolism, a behavior known as dormancy.
• A variety of environmental factors may cause the size of a population to increase or decrease. (This requires students to brainstorm examples of factors and predict the possible effects.)
• compare and contrast the factors that increase or decrease population size.

Long Term Changes

• Long-term changes may affect entire communities and ecosystems.
• Such large-scale changes include the addition of excess nutrients to the system (eutrophication), which alters environmental balance; dramatic changes in climate; and catastrophic events, such as fire, drought, flood, and earthquakes.
• predict the effect of climate change and the effect of eutrophication on ecosystems, communities, populations, and organisms.