Download Unit 8 -Ecology Populations, Communities, Ecosystems, and Biomes

Unit 8 -Ecology
Populations, Communities, Ecosystems, and Biomes
Living Things and the Environment - Section 21.1
Organisms obtain food, water, shelter, and other things it needs to live, grow, and reproduce
from its _______________________.
An environment that provides these things for an organism is it’s _________________.
Biotic and Abiotic Factors
The living parts of a habitat are called ____________________
__________________.
The nonliving parts of the habitat are called ____________________
__________________.
Levels of Organization
All the members of one species living in a particular area is a ________________________.
All of the different populations that live in an area and interact make up a _________________.
A community plus all of the abiotic factors in that habitat make an ______________________.
The study of how living things interact with each other and with their environment is called
______________________.
Studying Populations - section 21.2
Determining Population Size
1.
2.
3.
4.
Direct observation (count the organisms)
Indirect observation (look for signs of organisms)
Sampling (count the organisms in a small area and make an estimate)
Mark and Recapture Studies (capture, mark, and release organisms, then recapture and
look for marks)
Changes in Population Size
Populations can change in size when new members join the population, or when members
leave the population.
Births and Deaths
The ______________
amount of time.
______________ is the number of births in a population in a certain
The ______________
amount of time.
______________ is the number of deaths in a population in a certain
If birth rate > death rate, population size __________________
If death rate > birth rate, population size _________________.
Immigration and Emigration
______________________ means moving into a population.
______________________ means leaving a population.
Population Density
________________ ______________ is the number of individuals in an area of a specific size.
Limiting Factors
A ______________ factor is an environmental condition that causes a population to decrease.
1. Food and Water
2. Space
3. Weather
The largest population that an area can support is called carrying capactity.
3 Interactions among Living Things - Section 21.3
Remember: Because of ___________ ____________ every organism has a variety of
__________________ that are suited to it’s specific living conditions.
The role of an organism in it’s habitat is called its _________________. (what it eats, how it
gets the food, what eats it, how and when it reproduces, physical conditions it needs to survive)
1. Competition
Competition is the struggle between organisms to survive as they attempt to use the same
limited resources.
2. Predation
Predation is an interaction in which one organism kills another organism for food.
__________________have adaptations that help them catch prey.
__________________have adaptations that help them avoid being killed by predators.
3.Symbiosis
Energy Flow in Ecosystems - Section 22.1
Each of the organisms in an ecosystem fills the role of ___________, ___________, or
______________.
Producers
An organism that can make its own food is a ______________. They are the source of all the
food in an ecosystem.
Consumer
An organism that obtains energy by feeding on other organisms is a consumer.
Consumers can be carnivores, herbivores, or omnivores.
Decomposer
An organism that breaks down waste and dead organisms and returns the raw materials to the
environment is a ______________.
Food Chains and Food Webs
A ________________ is a series of events in which one organism eats another and obtains
energy.
A ________________ consists of the many overlapping food chains in a particular ecosystem.
Energy Pyramid
An ________________ shows the amount of energy that moves from one feeding level to
another in the food web.
The most energy is available at the producer level of the pyramid. As you move up the pyramid,
each level has less energy available than the level below.
Changes in Communities - Section 21.4
The series of predictable changes that occur in a community over time is called succession.
___________________ is the series of changes that occur in an area where no soil or organisms exist.
The first species to populate an area are called the pioneer species.
___________________ occurs in a place where an ecosystem currently exists.
Lichens are compound creatures, formed from the symbiotic relationship between a algae and a fungus.
They grow on rocks, tree trunks and branches.
When lichens die they create a weak acid that eats away at the rock, creating a soil where mosses can
grow and in time larger bushes.
Lichen are pioneer plants in succession.
Cycles of Matter - Section 22.2
The Water Cycle
The processes of ______________, ____________ and _______________ make up the ______________
___________________.
The Carbon and Oxygen Cycle
The carbon and oxygen cycle traces the way producers, consumers, and decomposers each play a role
in the linked recycling of carbon and oxygen in ecosystems.
The Nitrogen Cycle
In the nitrogen cycle, nitrogen moves from the air to the soil, into living things, and back into the air.
Freshwater Ecosystems
Freshwater ecosystems include streams, rivers ponds and lakes.
Streams and Rivers
•
Water currents flow strongest in streams which flow and join together forming larger, but
slower moving rivers.
•
Ponds and Lakes
•
Ponds are smaller bodies of still water where light can often reach the bottom.
•
Lakes are generally larger than ponds and the water temperature varies between the top and
the bottom depending on the season.
•
Freshwater Ecosystems
Organisms Adaptations
•
Freshwater Ecosystems
Organisms Adaptations
•
Adaptations:
•
After reading about the organisms found in freshwater ecosystems explain what types of
organisms are found in each environment, and what adaptations make them well suited for that
environment.
•
_______________ – a consumer that eats dead organisms
•
____________________ – the first consumer in a food chain (eats a producer)
•
_____________________ – the second consumer in a food chain (eats a primary consumer)
•
_____________________ – a fully established (developed) ecosystem after succession.
•
BIOMES
•
A __________________ is a group of land ecosystems with similar climates and organisms.
•
It is mostly the climate (temperature and precipitation) that determines its biome.
(That is because the types of organisms that can live in an area depends a lot on the climate.)