ECOSYSTEM STABILITY
ENERGY FLOW
CORAL REEF CRISIS
100
MOJAVE DESERT
COMPETITION & INTERACTIONS
CRITICAL THINKING
100

This term describes a chain reaction of ecological changes caused by disruption to one population. 

A. Competition
B. Mutualism
C. Cascading Effect
D. Adaptation

C. Cascading Effect

100

This process allows producers to convert sunlight into usable chemical energy.

A. Respiration
B. Decomposition
C. Photosynthesis
D. Competition

C. Photosynthesis

100

This relationship exists between coral and algae.

A. Competition
B. Mutualism
C. Predator-prey
D. Parasitism

B. Mutualism

100

This abiotic factor MOST limits desert populations.

A. Oxygen
B. Water availability
C. Predator populations
D. Biodiversity

B. Water availability

100

Competition occurs when organisms require the same limited:

A. Adaptations
B. Ecosystems
C. Resources
D. Predators

C. Resources

100

This term describes the role an organism plays within an ecosystem.

A. Biodiversity
B. Niche
C. Trophic Level
D. Adaptation

B. Niche

200

Which scenario would MOST likely destabilize an ecosystem fastest?.

A. Increased biodiversity
B. The sudden removal of producers
C. Seasonal rainfall variation
D. Predator migration

B. The sudden removal of producers

200

Which organism would MOST likely contain the LEAST available energy?

A. Grass
B. Rabbit
C. Snake
D. Hawk

D. Hawk

200

Coral reef biodiversity would MOST likely decrease if:

A. Shelter availability increased
B. Algae populations disappeared
C. Predator populations stabilized
D. Nutrient cycling improved

B. Algae populations disappeared

200

Which adaptation BEST helps desert organisms survive?

A. Increased daytime activity
B. Water storage and reduced heat exposure
C. Dependence on abundant rainfall
D. Elimination of competition

B. Water storage and reduced heat exposure

200

Which pair is MOST likely competing?

A. Coral and algae
B. Bobcat and jackrabbit
C. Mule deer and jackrabbit
D. Fungus and bacteria

C. Mule deer and jackrabbit

200

Which ecosystem would MOST likely recover fastest after disturbance?

A. An ecosystem with one producer species
B. An ecosystem with low biodiversity
C. An ecosystem with many interconnected species
D. An ecosystem without decomposers

C. An ecosystem with many interconnected species

300

A prey population increases rapidly after predator decline. Predators were MOST likely acting as:

A. Producers
B. Limiting Factors
C. Abiotic Factors
D. Decomposers

B. Limiting Factors

300

Why are large predator populations difficult to maintain in ecosystems?

A. Predators cannot consume producers
B. Less energy is available at higher trophic levels
C. Producers eliminate predators
D. Abiotic factors stop energy transfer

B. Less energy is available at higher trophic levels

300

Many reef fish depend on coral structures primarily for:

A. Shelter
B. Sunlight
C. Rainfall
D. Decomposition

A. Shelter

300

The Phainopepla and mistletoe relationship demonstrates:

A. Competition
B. Predator-prey
C. Mutualism
D. Commensalism

C. Mutualism

300

Two predators consuming the same prey demonstrate:

A. Mutualism
B. Competition
C. Photosynthesis
D. Decomposition

B. Competition

300

A producer population crash would MOST directly affect this trophic level FIRST.

A. Tertiary consumers
B. Apex predators
C. Primary consumers
D. Decomposers

C. Primary consumers

400

If an invasive species consumes resources more efficiently than native organisms, native populations would MOST likely:

A. Increase in biodiversity
B. Outcompete the invasive species
C. Decline due to competition
D. Become abiotic factors

C. Decline due to competition

400

A decrease in phytoplankton populations would MOST directly affect this group FIRST.

A. Tertiary consumers
B. Primary consumers
C. Abiotic factors
D. Decomposers

B. Primary consumers

400

If coral bleaching continues for many years, fish populations would MOST likely:

A. Increase due to reduced competition
B. Remain unchanged
C. Decline due to habitat loss
D. Become producers

C. Decline due to habitat loss

400

If water availability suddenly increased in the Mojave Desert, producer populations would MOST likely:

A. Decline immediately
B. Remain unchanged permanently
C. Increase temporarily
D. Stop photosynthesis

C. Increase temporarily

400

Mutualism differs from parasitism because:

A. Both organisms benefit
B. One organism is harmed
C. Producers are eliminated
D. Abiotic factors increase

A. Both organisms benefit

400

If decomposers disappeared from ecosystems, nutrients would MOST likely:

A. Recycle more efficiently
B. Remain trapped in dead organisms
C. Increase producer growth immediately
D. Eliminate competition

 B. Remain trapped in dead organisms

500

An ecosystem with many interconnected food web relationships is generally MORE stable because organisms:

A. Require less energy
B. Stop competing for resources
C. Have alternative food sources and interactions
D. Depend less on producers

C. Have alternative food sources and interactions

500

This group of organisms recycles nutrients back into ecosystems.

A. Producers
B. Herbivores
C. Decomposers
D. Apex Predators

C. Decomposers

500

Coral reefs are considered highly stable ecosystems partly because of their:

A. Lack of predators
B. Limited competition
C. Biodiversity
D. Abiotic factors only

C. Biodiversity

500

Competition in desert ecosystems is often especially intense because resources are:

A. Unlimited
B. Shared equally
C. Constantly increasing
D. Limited

D. Limited

500

If two species occupy the same niche for a long period of time, one species may eventually:

A. Become a producer
B. Stop competing
C. Be eliminated from the ecosystem
D. Become abiotic

C. Be eliminated from the ecosystem

500

Why are ecosystems with higher biodiversity often more stable?

A. More species provide alternative food web pathways
B. Predators disappear more quickly
C. Competition no longer occurs
D. Producers require less sunlight

A. More species provide alternative food web pathways

600

A drought decreases producer populations. What is the MOST likely long-term effect on tertiary consumers?

A. Tertiary consumers increase rapidly
B. Tertiary consumers become producers
C. Tertiary consumers remain unaffected
D. Tertiary consumers decline due to reduced prey availability

D. Tertiary consumers decline due to reduced prey availability

600

Why do ecosystems require large producer populations?

A. Most energy is lost between trophic levels
B. Producers consume decomposers
C. Predators create energy
D. Producers eliminate competition

A. Most energy is lost between trophic levels

600

Why does the coral-algae relationship increase ecosystem stability?

A. Coral eliminates predators
B. Both organisms benefit and support reef survival
C. Algae consume coral
D. Coral prevents photosynthesis

B. Both organisms benefit and support reef survival

600

Why could a prolonged drought affect predator populations even if predators are not directly losing water?

A. Predators stop hunting during droughts
B. Prey and producer populations decline first
C. Predators become decomposers
D. Drought only affects producers

B. Prey and producer populations decline first

600

Why may competition increase after droughts or habitat destruction?

A. Resources become more available
B. Organisms require less energy
C. Fewer resources force organisms to compete more intensely
D. Predators disappear permanently

C. Fewer resources force organisms to compete more intensely

600

Why can removing a keystone species disrupt an entire ecosystem?

A. Keystone species eliminate producers
B. Many organisms depend on them directly or indirectly
C. Keystone species prevent competition entirely
D. They control all abiotic factors

B. Many organisms depend on them directly or indirectly