Ecology
Chapter 3 and 4.2
3-1 What Is Ecology?
 Ecology is the scientific study of _______________________________________
__________________________________________________________________
 All life on Earth is interconnected.
 All life interacts with the nonliving environment.
The Biosphere
The biosphere contains the combined portions of the planet
in which all of life exists, including:
•
•
•
The biosphere extends from about ______ kilometers above
Earth's surface to as far as ____ kilometers below the surface of the
ocean.
Interactions and Interdependence
– Interactions within the biosphere produce a web of interdependence between
____________________ and the __________________________ in which they
live.
– The interdependence of life on Earth contributes to an _____________________,
or dynamic biosphere.
Levels of Organization
•The biosphere is divided into biomes. A biome is a group of
_____________________ that have the same _______________
and similar dominant communities.
•An _____________________is a collection of all the organisms
that live in a particular place, together with their nonliving, or
physical, environment.
Levels of Organization
•Communities are assemblages of _____________ populations that live
together in a defined area.
•Populations are groups of individuals that belong to the ____________
species and live in the ________________ area.
•A species is a group of organisms so similar to one another that they can
__________________ and produce ____________________________.
Ecological Methods
– Regardless of the tools they use, scientists conduct modern ecological research using
three basic approaches:
•
•
•
– All of these approaches rely on the application of scientific methods to guide
ecological inquiry.
Learning Checkpoint
1. The combined portions of the planet in which life exists, including land, water, and the
atmosphere, form the _______
2. A group of organisms that can breed and produce fertile offspring is known as a
3. What does an ecosystem include?
4. An ecological method that uses mathematical formulas based on data collected is
5. An ecologist marks out an area in a specific ecosystem and proceeds to identify the
number of insect species in the area. This is an example of ecological
3-2 Energy Flow
Producers
•Organisms that are able to capture energy and
carbon from the non-living world and form organic
compounds are called _______________________
•Autotrophs are also called _____________________
because they are the source of energy for the rest of
the living world.
•Without a constant input of _________________,
living systems cannot function.
–_____________________-is the main energy
source for life on Earth.
–_____________________ can also be a
source of energy for some bacteria.
Consumers
•Many organisms cannot harness energy directly from the physical environment.
•Organisms that rely on other organisms for their energy and food supply are called
__________________________________
•Heterotrophs are also called ____________________.
Typers of Heterotrophs
•______________________________ eat plants.
•______________________________ eat animals.
•______________________________ eat both plants and animals.
•______________________________ feed on plant and animal remains and other dead
matter.
•______________________________ like bacteria and fungi, break down organic
matter.
Feeding Relationships
•The relationships between producers and consumers connect organisms into feeding
networks based on who eats whom.
•Energy flows through an ecosystem in one direction:
→
Food Chain
→
Food Web
o Remember: arrows represent flow of
energy!
Ecological Pyramids
– Ecologists recognize three different types of ecological pyramids:
• __________________ pyramids (show the transfer of energy)
• __________________ pyramids (show the organism mass at each level)
• pyramids of ________________ (show the amount of organisms in each level)
Energy Pyramid
•Shows transfer of energy through trophic levels (who eats what)
→
→
→
→
•10% Rule
–Only 10% of the energy in the previous trophic level is passed on
•Biomass
–Total quantity of living matter at each trophic level
Learning Checkpoint
1. The main source of energy for life on Earth is?
2. Organisms that feed on plant and animal remains and other dead matter are?
3. How does a food web differ from a food chain?
4. In a biomass pyramid, the base of the pyramid represents the mass of?
5. The amount of energy represented in each trophic level of consumers in an energy
pyramid is about?
3-3 Cycles of Matter
•Remember CHNOPS?
•Unlike energy, these important elements can be _______________________ within and
between ecosystems.
•Biogeochemical cycles- the passing of matter from one organism to another and from
one part of the biosphere to another
Nutrient Limitation and Surplus
•What is a limiting nutrient?
•Why do farmers use fertilizer?
•How does the use of fertilizer disrupt other parts of the ecosystem?
4-2 What Shapes an Ecosystem?
•
Ecosystems are influenced by both _______________(living) factors and
____________________ (nonliving) factors.
•
What are some examples of biotic factors in an ecosystem?
•
What are some examples of abiotic factors in an ecosystem?
The area where an organism lives is called its Habitat.
A Niche is the role of an organism with in its habitat. What does it eat? What preys on
it? What resources does it use? How does it interact with other organisms? Etc.
Community Interactions
• When organisms live together they interact constantly.
• Interactions include:
–
–
–
Competition
• No two species can occupy the same niche at the same time. This is called the
__________________________________________
• Organisms compete for __________________ and available ______________.
Predation
• An interaction in which one organism captures and feeds on another organism
Symbiosis
• 2 species living together
– ____________________ (both species benefit)
– ____________________ (one benefits, the other is not helped nor harmed)
– ____________________(one organism lives in or on another and harms it
by stealing nutrients
Ecological Succession
• Ecosystems are constantly changing naturally and due to human disturbances.
• Older inhabitants _____________, new organisms ___________
• When a habitat has been completely wiped out so that
all that remains is rock _____________________________
occurs.
Secondary Succession
• When a disturbance of some kind changes a community without removing the soil