Unit 9: Ecology
Name:
Aim 53: Recycling of Materials in an Ecosystem
Date:
In a self-sustaining ecosystem, various materials are recycled between the living organisms and their nonliving (abiotic)
environment. The recycling process allows materials to be used over and over again by the living organisms.
I.
Importance of Decomposers
Process carried out by _________________________ that involves the breaking down
of _______________ organisms, as well as the __________________ produced by
What is decomposition?
living organisms, into their __________ (original) materials and
_______________________ those materials to the ecosystem
Name two organisms
that occupy this niche
Organisms need _________________________ amounts of oxygen, carbon, nitrogen,
Why are decomposers needed
for a STABLE ecosystem?
hydrogen and water to carry out ____________________________ Decomposers begin
this ______________________ of materials so they can be re-used by the organisms.
a) Which letter represents the decomposers?
b) Explain your answers giving TWO reasons:
1.
2.
II.
Carbon-Oxygen Cycle
Which two processes are responsible for keeping the percentage of atmospheric oxygen at relatively constant
levels?
MATERIAL
Oxygen
(O2)
Carbon Dioxide
(CO2)
Which organisms RELEASE this material?
WHAT PROCESS is it RELEASED?
Which organisms USE this material?
WHAT PROCESS is it USED FOR?
RELEASED by… ________________________
USED by… ____________________________
Through the
PROCESS of… __________________________
Through the
PROCESS of… _________________________
RELEASED by… ________________________
USED by… ____________________________
Through the
PROCESS of… __________________________
Through the
PROCESS of… _________________________
a) What is the gas given off at arrow X that is absorbed by the plant? _______
What process is responsible for its release? _________________________
b) What is the gas given off at arrow Y that is absorbed by the human? ______
What process is responsible for its release? _________________________
III.
Nitrogen Cycle
Why is nitrogen important to organisms? It is part of the structure of _________________ & ________________
How does nitrogen cycle through the ecosystem?
1. _________________________ and soil bacteria break down the remains of dead organisms and __________________
their wastes and remains into compounds that can be ___________________ by plants
2. The plants ___________________ the nitrogen containing compounds from the _________________.
3. ________________________ then obtain nitrogen in the form of _______________________ in the foods that they eat.
1. Label #1-4 in the diagram below using the terms photosynthesis, respiration and decomposition.
The words can be used more than once
2. All of these important materials need to be cycled between the living and nonliving counterparts in an ecosystem,
however, what material is NOT
RECYCLED between organisms? ____________________