Name: ____________________________________ Date: _______________ Env. Science Period: _____
Unit 1: Ecology (Ch. 5)
I. Energy in Ecosystems
** The ____________________ of ____________________ through an ecosystem is one of the most
important factors that determines the system’s capacity to sustain life.
Adenosine Triphosphate (ATP)
What is ATP comprised of? ___________________, ____________________, and _________________
Where is energy stored in ATP? How is energy released? ______________________________________
_____________________________________________________________________________________
Interactions and Interdependence in Ecology
 Ecology is the study of ___________________ and relationships between __________________ and
their environment.
 What non-living things in their environment do organisms interact with? _______________________
_________________________________________________________________________________
 In what ways are these nonliving things essential to organisms? ______________________________
_________________________________________________________________________________
 ________________ contains the combined portions of the planet in which all of life exists, including
land, water, and air (atmosphere).
 Name the levels of organization within the biosphere (start from the smallest level to the largest level)
__________  __________  __________  __________  __________  __________
Producers




What is the main energy source for life on earth? ______________________________________
Producers are also known as __________________.
How do they get food? ___________________________________________________________
Name the two types of producers: __________________ and __________________
o Photo-autotrophs use __________________ in the process of photosynthesis.
o Chemo-autotrophs use __________________ __________________.
 Where do most producers get their energy from? ____________________
 Photosynthesis is the process by which producers use ___________________________________
______________________________________________________________________________
6CO2 + 6H2O

Light
energy
C6H12O6 + 6O2
 On land, _____________ are the main autotrophs but in freshwater ecosystems, _____________
are the main autotrophs.
 Cellular respiration is the process by which both autotrophs & heterotrophs ___________ energy
from food to do cellular work; it is the OPPOSITE of photosynthesis.
C6H12O6 + 6O2

energy + 6CO2 + 6H2O
Consumers




Consumers are also known as __________________.
These are organisms that reply on other organisms for their _______________ and food supply.
Consumers use the sun’s energy _______________.
The five (5) types of consumers/heterotrophs are:
1. _______________ - eat plants. Ex: rabbits
2. Carnivores — eat other ________________________. Ex: Lions, Sharks
3. Omnivores — eat BOTH _______________ and _______________. Ex: _____________
4. ______________ — eat plant and animal _______________ called detritus. Ex: vultures
5. Decomposers — ______________________ down organic matter. Ex: bacteria & fungi
Feeding Relationships
 Energy flows through an ecosystem in _______________ _____________________.
Sunlight

Producers

Consumers
Energy Transformations
 Only ______ of the energy at each _______________ _______________is passed on to the next.
 Primary – 1st
 Secondary – 2nd
Trophic levels
 Tertiary – 3rd
 Quaternary – 4th
 The other ______is lost as _____________when consumers burn food during cellular respiration;
this is good because it helps us to maintain our body temperature (homeostasis).
Food Chain
 What is a food chain? ____________________________________________________________
______________________________________________________________________________
 What does a food chain begin with? ___________; where do producers store energy? _________
______________________________________________________________________________
 Stored energy is passed on to ________________________ when they eat __________________
or other consumers.
Ex: Sun  Producer  ___________________  Secondary Consumer  _____________________
(Grass)
(Grasshopper)
(Snake)
(Hawk)
Decomposer
(Fungi)
Food Web
 What is a food web? _________________________
_________________________________________
________________________________________
Ecological Pyramids
 An ecological pyramid is a diagram that shows the relative amounts of __________________ or
matter contained within each ________________ ________________ in a food chain.
 There are three (3) types of ecological pyramids:
o Energy Pyramid - ________________________________________________________
_______________________________________________________________________
_______________________________________________________________________
o
_______________ _______________- represents the amount of living organic matter at
each trophic level. Usually, the greatest biomass is at the base (bottom) of the pyramid.
o
Pyramid of Numbers - ____________________________________________________
_______________________________________________________________________
_______________________________________________________________________
Recycling in the Biosphere
 Matter and energy move __________________ through the __________________.
 Energy flows __________________ way.
 Some energy is lost as ________________, only _______________ of energy is used directly by
organisms at each _______________ _______________.
 Matter is __________________ through the ecosystem.
o Law of Conservation of Matter
o Matter can be _________________
II. Ecosystems, Communities & Population Growth
Factors in an Ecosystem
 Biotic factors: __________________________________________________________________
______________________________________________________________________________
o Examples: insects, plants,
 Abiotic factors: _________________________________________________________________
______________________________________________________________________________
o Examples: sunlight, wind, soil
Community Interactions
 ___________________ occurs when organisms attempt to use an ecological resource in the same
place and at the _______________ time.
o A ________________ is any necessity of life. Examples are: water, nutrients, light, food,
space
 What is predation? ______________________________________________________________
______________________________________________________________________________
o Ex.: lions hunt deer so lions are the predators and deer are the prey
 There are three (3) main types of Symbiosis. These are ____________, _____________, and
_______________.
o Mutualism - _______________ organisms benefit from the relationship.
 Ex: ______________________________________________________________
o _______________ - one organism _______________ while the other organism is neither
helped nor _______________.
 Ex: ______________________________________________________________
o Parasitism - _______________ organism _______________ at the expense of the other
organism which is harmed.
 Ex: ______________________________________________________________
Ecological Succession
Ecological succession is ___________________ changes that occur in a community over time.
 Primary succession: _____________________________________________________________
______________________________________________________________________________
o Ex: after a volcanic explosion where the land is covered with lava/ashes
o Pioneer species is ________________________________________________________
________________________________________________________________________
 Secondary succession: ___________________________________________________________
______________________________________________________________________________
o Ex: wildfires, plowing, logging industry
Population Growth
 Population growth is affected by three (3) factors: _______________, _______________, and
number of organisms arriving or leaving (immigration or emigration).
 _______________ and immigration increase the population.
 Death and _______________ decrease the population.
 There are two ways growth can occur in a population: exponential growth and logistic growth.
o Exponential growth occurs when organisms in a population _______________ at a
_______________ _______________; J-shaped curve.
 Exponential growth tends to happen when resources are _______________.
o Logistic growth happens when resources become _______________ available so growth
will _______________ or _______________; S-shaped curve.
 Logistic growth happens when a population reaches its carrying capacity due to
_______________ _______________.