Biology
Chapter 3 Section 1
Communities and Biomes
Life in a Community
n Some ____________________________ in one part of the world are suitable for supporting certain forms of life.
Limiting Factors
n Factors that affect an organism’s _____________________________________ in its environment. Any biotic or abiotic factor that restricts the ____________________, _______________________, ___________________________, or ____________________________________
n ______________________________________
n ______________________________________
n ______________________________________
n ______________________________________
n Factors that limit one population in a community may also have an __________________________________ effect on another population.
n Reduced grass due to a lack of water will cause a reduced amount of mice. Hawks will reduce in number due to a reduction in the ___________________________
Ranges of Tolerance
n _______________________________ is the ability of an organism to withstand __________________________________ in biotic and abiotic environmental factors.
Succession: Changes over Time
n __________________________ – orderly, ___________________ changes and species replacements that take place in the communities of an ecosystem.
n Occurs in stages, at each step conditions are suitable for some organisms but not for others.
n Can take _________________________________________ to occur
n Two types: ______________________________________________________
Primary Succession
n Colonization of __________________ land by communities of organisms.
n Land after _____________________________
n First species to take hold in an area is called the ___________________________. Usually small organisms.
n Pioneer species eventually die. These decaying organisms along with bits of sediment in cracks and crevices of rock, make up the first stage of _______ development.
n After time, primary succession slows down and the community becomes fairly____________________, or reaches______________________.
n A _____________________________________________ community that undergoes little or no change in species is a __________________________________.
n Climax community may last for ____________________________ of years.
n Stability or equilibrium does not mean that change ___________________.
Secondary Succession
n The sequence of changes that take place after an existing community is _______________________________________ in some way.
n Occurs where there was____________________________, and on land that previously contained ______________________.
n Since soil already exists, takes much less time than ________________________________ to reach a climax community.
Chapter 3 Section 2
Biomes
What is a biome?
► Ecosystems that reach similar climax communities can be grouped into a broader category called a __________________.
► ___________________________________ biomes
► Aquatic biomes – 1. _________________________ 2. _______________________
Marine Biomes
► Different parts of the ocean differ in ____________________________________.
► Oceans contain a lot of ___________________, or __________________ material. Most is made up of extremely small, often ____________________, organisms that humans actually don’t see but large marine animals, such as the baleen whales, depend upon.
► One way ecologist study marine biomes is to make separate observations in _____________________, ________________ zones (___________________ zones) and _________________, ___________________ zones (_________________ zones.)
► ________________ zone – bays, rocky shores, sandy beaches, mudflats, and estuaries
► _______________ zone – ___________________, least explored areas
Estuaries – Mixed waters
► ____________________ – _______________ body of water, partially surrounded by __________, in which __________________________________ water mix.
► ____________________ – amount of ______________ in the water
► Salinity is between that of seawater and fresh water. Salinity changes with the __________ so a ______________________________ of organisms can live in estuaries.
The Effects of Tides
► The __________________________ pull of the sun and moon cause the rise and fall of ____________________________.
► _______________________ zone – the portion of shoreline that lies between the ______________________________ lines.
► Size depends on the ____________________________ and the difference between the high and low tides
► ____________________ ecosystems have high levels of ___________________, ________________________, and ___________________________
► ____________________ pools = pools of water left when the water is at _________________ tide, can isolate the organisms that live in the _________________ zone until the next high tide.
► Therefore, these areas can vary in _____________________________________ from one time of day to another.
► Intertidal zones differ in ________________________________ action.
► Intertidal animals have adaptations that act by ______________ to hold onto wave-beaten rocks. Others secrete ________________ that helps them keep anchored. Others animals survive by ____________________ into the sand.
In the Light
► Deeper into the ocean, the bottom is less affected by __________________________.
► __________________________ washed from the __________ by rainfall and runoff contribute to the abundant ___________ and high ____________________ of this region of the ___________________ zone.
► Most of the organisms that live in the marine biomes are ____________________. Small organisms that _________________ and _________________ in the waters of the _________________ zones. This includes autotrophs, diatoms, and the juvenile stages of many marine animals. Plankton are important because they form the _______________ of all aquatic ____________________.
In the Dark
► Extreme _________________ and ____________________
► Animals here are far below the __________________ zone where ______________ abound. Many still depend on plankton for ______________, with directly, or indirectly, by eating organisms that feed on _____________________
Freshwater Biomes
► ______________ and ____________
► Cold water is ________________ than warm water
► These _____________________ variations within a lake are an abiotic factor that limits the kinds of organisms that can survive in deep lakes.
► __________________ is another limiting abiotic factor. Not enough light reaches the bottom to support ____________________, so few aquatic plants or algae grow. Population _____________________ is lower in deep water. As dead organisms drift to the bottom, ________________ use oxygen to break them down and recycle the nutrients. Decay takes place more slowly at the bottom of a lake.
Other Aquatic Biomes
► Other places where land and water meet are called _________________. There are several kinds.
► Swamps have _______________
► Marshes do not. Found inland and in coastal regions
► Both are highly _______________________ and are the source of food for many migratory bird and other animals.
► ________________, get their water supply from _____________. Water does not _________ through them.
Terrestrial Biomes
► The location of earth determines the types of ____________________ biome.
Latitude and Climate
► Latitude describes your position in degrees north and south of the ________________. At different ___________________ the sun strikes Earth differently. As a result, the _________________ – wind, cloud cover, temperature, humidity and _______________________ in that area – is different
Life on the Tundra
► Traveling south from the north pole, you reach the first of two biomes that circle the
________________________.
► Tundra – __________________ land with long summer days and short periods of winter sunlight.
► Because of its latitude temperatures never rise above __________________ for long, and only the topmost layer of the soil thaws during the summer. Underneath this top layer is a layer of permanently frozen ground called _____________________.
► Topsoil is so thin it can support only _________________________ and other small plants. The soil lacks _______________________
► The process of decay ______________________ due to the _______________ temperatures and, as a result, nutrients are not recycled _________________.
Life on the Taiga
► Also circle ___________________ pole
► Also called the __________________ or _______________________________ forest. Forms an almost continuous belt of ____________________ trees. Larch, fir, hemlock, and spruce trees
► Somewhat ________________ and _______________ then _________________
► ___________________ winter and __________________ summers
► Much of Canada, Northern Europe, and Asia
► ____________________ usually absent
Life in the Desert
► ______________ biome
► Arid region with sparse to almost nonexistent _____________ life.
► Less then _____ cm precipitation annually.
► ___________________ Desert in Chile is world’s driest place
Life in the Grassland
► Usually where ____________________ cm of precipitation falls.
► Large communities covered with rich soil, grasses, and similar plants.
► Occur in climates that experience a __________ season where insufficient ____________ exists to support forests
Life in the Temperate Forest
► Precipitation is 70 to 150 cm annually in the ___________________ zone.
► _________________________________ forests are dominated by ___________________________ hardwood trees that lose their foliage _________________.
Life in the Rain Forests
► Home to ______________________ of organisms than any other biome on Earth.
► 2 types: 1. ____________________________ 2. _____________________________
► Temperate rain forests are found on the Olympic Peninsula in _____________________ state and in other places throughout the world, such as South America, New Zealand, and Australia.
► Extensive amounts of _____________________ in the rain forests.
► Tropical rain forest have ____________ temperatures, _____________ weather and lush __________________ growth. These are found near the __________________.