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The Ecosystem
Slide 2
__________________________________________ live together in communities.
The structure of the interaction between different populations and their physical
environment is called the________________________.
.
Slide #4, 5 & 6
Biotic Factors:
I. Feeding Levels
A. _________________________ are ___________________
List 6 Examples:
B. _________________________ are _________________________
1.First Order consumers or _________________________
List 6 Examples:
2. Second Order consumer or __________________________ (some
omnivores) List 6 Examples:
3.Third Order consumer or ___________________________
List 6 Examples:
C. The order in which these feed is called the _______________________ chain.
D. Overall _________________________ community members is a food
_________________.
E. ____________________________ are both carnivores and herbivores.
F. ____________________________ an animal that feeds on ______________________ (dead
animals), dead plant material or refuse.
G. ________________________________ break down _______________________ (having
carbon) material.
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Slide #7
II. Pyramid of Energy:
A. _________________ is lost between each level of consumer (about _______ percent).
B. To show this lost a _____________________________ of energy can be drawn
C. Potential energy is lost because some energy is _______________ by the organism to
carry on life functions.
D. Each level is called a __________________ (feeding) level
Slide #8 & #9
III. Pyramids of Numbers and Biomass:

Most food chains have only _______ links, too much energy is lost to support 4th & 5th
order consumers.

As the level of consumer increases, the number of consumers _______________________
forming a pyramid of numbers

_________________________________ is the mass of living biological organisms in a given area or
ecosystem at a given time.

Higher feeding levels have _____________ biomass, forming a pyramid.

Each ________________________ level receives about ____________________________ of the energy
from the previous level.
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Slide #10
IV. Recycling of Materials:
Cycles of Matter
A. Matter cannot be __________________________________, therefore it must be recycled.
B. _____________________________ (bacteria, fungi) release materials in dead organisms
and waste.
C. __________________________ (crabs, buzzards, jackals) feed on ________________ (dead
animals).
Slide #11
IV. Nitrogen Cycle
Three pathways of recycling
1. Decomposer bacteria in soil attack proteins in dead animals & waste
a. _______________________________ be absorbed by plants
b. one group of bacteria converts amino acids to ammonia this is
____________________________________.
c. another bacteria then converts ammonia into nitrate ions this is called
____________________________________________.
2. Nitrogen-fixing bacteria live in roots of __________________________.
a. plants form _________________________ (a swelling on a root)
b. both organisms benefit (___________________________ relationship)
3. Denitrifying bacteria drains nitrogen from an ecosystem by freeing it into the
atmosphere.
Slide #12, 13, 14 & 15
IV. Other Biotic Relationships
_____________________________________ — long-term interactions between different biological
species.
Three Types
1. _____________________________________
2. _____________________________________
3. _____________________________________
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IV. Other Biotic Relationships (cont.)
1. _____________________________________ one organism benefits from a host without
harming or benefiting host.
2. ____________________________________ is when two organisms depend on each other
and both benefit.
3. ___________________________________ is when one organisms is completely depend on
the other at some point in its life cycle and ___________________ the host.
Slide #16—#17
V. Abiotic Factors of Environment:
I Medium
A. Substance in which an organism lives.
B. Density
C. Gas exchange
Slide #18—#17
II. Water
A. Water cycle or _____________________________ cycle
B. Amount of rainfall determines distributions of _________________________ or land
plants.
C. Water _________________________________________ from ocean and forms clouds.
D. Water falls from clouds as rain (______________________________________).
E. Water will hit the ground and then…
i. ________________________________ from surface forming lakes and rivers.
ii. Seeps (_______________________________) into ground becoming
__________________________ ____________________________________.
F. Water is taken into plants & (as a by-product of ________________________________) is
given off (__________________________________________) in the form of water vapor.
G. Water also ______________________________________________ from lakes and rivers.
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IV. Other Biotic Relationships (cont.)
III. Soil
A. Rock breaks down by ______________________________.
B. ____________________________________________ is the process of chemical or physical breakdown
of the minerals in the rocks.
Example: rain
C. Rock mixed with decayed organic material is called ______________________________.
D. Soil forms layers, the layer closest to surface is called ______________________ and is high in
organic material.
IV. Light
A. _____________________________________--- exposure
B. Only _______________—________________ percent of total solar radiation (light striking earth) is
used for photosynthesis.
Slide #23
V. Temperature & Metabolism
A. As temperature changes so does metabolism.
B. Limits where life can live

Usually between 0° C to 50°C
C. _______________________________ (also spelled estivation) is the response to hot or dry
conditions sometimes called summer dormancy
D. ______________________________ winter dormancy.
Slide #24 &#25
V. Distribution of Organisms
A. Succession is how community changes over time.
B. As a community ages it goes through different stages.
C. The type of plants are the key to the stage the community is in.
D. Two types of succession
a. _______________________________ succession (first)
b. .______________________________ succession (areas that have been disturbed)
Slide #24 &#25
V. Distribution of Organisms (cont.)
_________________________________ succession (first)
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1. Begins when _______________ ________________ is formed, like lava or when rock is
exposed for the first time.
2. ____________________________ ________________ take hold in this new environment.
a. These are _______________ _____________________________
b. Examples
i. __________________________ (symbiotic relationship between algae and
fungi)
ii. _________________________
3. __________________________________ community
a. This is a community that has reached a ______________________ ________________
under a particular set of environmental conditions.
b. These are the ____________________________ communities resulting from
succession, and the represent the community which makes the most
___________________________ _________________ of available resources.
_____________________________ succession
a. Occurs on substrate that previously supported vegetation before a
_____________________ destroyed the plant life.
b. Is a _______________________________________ to a disturbance, for example, forest
fire, tsunami, flood, or an abandoned field.