The document provides a review for an APES Unit 2 test, covering topics like the water, carbon, and nitrogen cycles, photosynthesis, population growth, ecological succession, and species interactions like mutualism, competition, and predation. Bellringer questions are presented on key concepts, and notes are provided explaining processes like keystone species, limiting factors, and natural and anthropogenic impacts on ecosystems.

1. APES Unit 2 Test
Review
Made by Jordan Randles

2. Bellringer Review
The most abundant element in the
atmosphere is Nitrogen
Photosynthesis is when plants absorb light to
gain energy
Energy cannot be lost but is converted to
heat
The Ozone Hole does not increase surface
temperature because it has UV rays, and UV
rays do not produce heat

3. Bellringer Review
Usually endangered species are
specialists because they cannot keep up
with change
Limiting factors for plants in the
rainforest include: light, phosphorus,
nitrogen and potassium
Commensalism, mutualism, parasitism

4. Bellringer Review
The biomes, chaparral and grasslands,
are adapted to intermediate wildfire
disturbance
Humans interfere with the carbon cycle
by burning fossil fuels and cutting trees

5. Water Cycle
This consists of
evaporation, precipitation
and transpiration.
Evaporation and
precipitation act as mutual
distillation. Humans draw
too much water, clear
vegetation that disrupts
the natural cycle and
increase flooding by
draining wetlands.

6. Carbon Cycle
There is more warm CO2 than
cold CO2. Terrestrial and aquatic
producers remove CO2. Oxygen
consuming producers, consumers
and decomposers carry out
aerobic respiration which
releases CO2. Humans take away
trees that absorb CO2 and burn
too many fossil fuels

7. Nitrogen Cycle
N2 makes most of the
atmosphere. Lighting and
rocks with nitrogen fix
bacteria emit N2.
denitrification is when
bacteria breaks down nitrogen
into simpler form. Human
destruction of forests releases
nitrogen. Humans add excess
nitrates to bodies of water,
remove nitrogen from top soil
when we harvest and burn on
clear grasslands.

8. Nitrogen Cycle
Nitrogen Cycle: Vital for organisms
Nitrogen Fixing: converting atmospheric
nitrogen gas to useful ammonia and ammonium
Nitrification: converting ammonium into
nitrites and nitrates
Denitrification: the opposite of nitrification
Ammonification: converting organic nitrogen
to ammonium

9. Phosphorus Cycle
Known as a sedimentary cycle, it is found
in sediments and rocks
These rocks rise in ridges and mountains
and then weathers away by erosion
becoming available to other organisms to
use
Plants can use it on the soil, and animals
eat these plants

10. Producers and
Consumers
Producers Consumers
Use Photosynthesis and Use cellular respiration to break
Chemosynthesis down complex organic compounds
into cellular energy
Divided into groups:
Primary
Secondary
Third and higher level
and Decomposers

11. Energy
First Law of Thermodynamics: Only about 10% of useable
Energy input always equals energy is transferred
energy output from level to level.
Ecological Efficiency is this
Second Law of Thermodynamics: percentage
Energy always goes from a more
useful to a less useful form when it
changes from one form to another
Law of Conservation of
Matter: We cannot create or
destroy matter

12. Notes in a Nutshell
Feedback Loop:
causes a system to
The top three ecosystems for NPP: change further in
the same direction
Tipping Point: the
level at which a
problem causes an
Swamp/ irreversible shift to
Rainforest Estuary the behavior of a
Marsh system
NPP is the net primary productivity Synergy: interaction
which is the remaining energy at the bet ween t wo or
more factors so that
rate at which an ecosystem's producers the combined effect
capture and store a given amount of is greater than the
sum of individual
chemical energy as biomass effects

13. Niches
Generalists have a broad niche Specialists have a small niche
They prefer variable They prefer constant
conditions because generalists conditions because there is less
can adapt competition

14. Nonnative Species and
Indicator Species
Other names for nonnative Indicator Species
species: exotic, alien and
invasive They can show when events
are coming such as
Nonnative species can spread temperature change, habitat
so rapidly because they lack loss, pesticides, plant issues,
predators and disease etc.
Frogs are unique because they
are vulnerable to all types of
water impurities

15. Keystone and
Foundation Species
Keystone species have a Foundation species create
large effect on types and the or enhance their habitats
abundance of other species which benefit others
Keystone influences
Foundation alters habitat
function

16. Interactions
Predators and prey have to Species compete when
adapt, and when they have to there is an overlap in
they partition resources resource use
Gauss's principle states that no
2 species cannot occupy the
exact same niche for very long

17. Population
Most animals cluster where resources
are available, for a better chance of
finding prey, protection from predators
in numbers and also temporary groups
for mating
Uniform dispersion allows room for
others to grow

18. Population
Equation for population change:
(births + immigration) - (deaths + emigration)
Populations will no grow indefinitely because they are limited
by limiting factors such as light, water, space, nutrients, food
and competition

19. Genetic Variation
Steps to EVOLUTION
Development of genetic variation due to
mutations in reproductive cells
Natural Selection
Selecting genetically based traits
that enhances a species’ ability to
sur vive & reproduce
These traits must be heritable

20. Changing Conditions
If environmental conditions change, organisms have three
options to either adapt, migrate or become extinct

21. Directional Selection
Directional Selection is when organisms shift in one direction
(such as towards one extreme)

22. Stabilizing Selection
Stabilizing Selection is when organisms fall into the average
and there are small amounts of the extremes

23. Disruptive Selection
Disruptive Selection is when organisms fall into both of the
extremes

24. Types of Extinction
Background extinction is when one to
five species per million species go extinct
each year
Mass extinction can be global,
catastrophic events that is far above
the more natural rate of one to five
species per year

25. Ecosystem Services
An ecosystem service is the benefits
that humans obtain from natural
ecosystems
An intrinsic value is one that depends
on personal opinion

26. Natural Ecosystems
Natural Ecosystems help remove impurities
from our environment, which provides us with
more time to deal with climate change than we
other wise would’ve
Examples include: Pollination of food crops,
natural pest control, they filter harmful
pathogens and chemicals from the water, and
add billions of dollars of revenue to ser vices
that it would have been costly to do other wise

27. Ecological Succession
Ecological succession is the gradual
change in species composition in a given
area
There are t wo types of succession,
primary succession and secondary
succession

28. Primary Succession
They start to form soil by
trapping wind-blown soil
particles and tiny pieces of
detritus and add it to their
own wastes and dead
bodies. As the lichens
spread over the rock moss
starts growing in the
Before producers move into an area cracks, and once they
pioneers such as lichens and mosses spread they form a mat
must be present on bare rock, that traps moisture and a
newly cooled lava,etc. layer of nutrients forms

29. Secondary Succession
With soil already there,
new vegetation can begin
to grow within a few
weeks. The seeds are
imported by winds, birds,
and other animals.
Includes abandoned farmland, burned or
cut forests, heavily polluted streams,
land that has been flooded, etc.

30. Terms
Facilitation: When one species betters
an area for another species but itself
Inhibition: When early species hinder
growth of other species
Tolerance: When late successional
plants are largely unaffected by plants
at earlier stages of succession

31. Limiting factors for
Marine Ecosystems
Temperature
Dissolved Oxygen
Availability of food and light
Nutrients

32. Zones of Freshwater
Streams and Rivers
Zone Clarity Speed Temp DO
Source Zone clear fast cold very high
Transition Zone med med med med
Flood-Plain Zone low slow high low

33. Review
Study! The Final (or test) is coming!
Study the following
Your notebook
Your bellringers (if you have them...)
Your study guide(s)
Your APES BOOK (see teacher for
chapters)

34. by Jordan Randles