5A1 Relationship in Ecosystem

Question 1

Define:

Ecosystem

Answer 1

A biological community of interacting organisms and their physical (abiotic) environment.

Question 2

Define:

Symbiosis

Answer 2

A close and long-term biological interaction between two different species, which can be mutualistic, commensal, or parasitic.

Question 3

Define:

Endosymbiosis

Answer 3

When a smaller organism lives within the cells, tissues, or some other structure inside a host organism’s body.

Question 4

Define:

Ectosymbiosis

Answer 4

When an organism lives on the surface of another organism.

Question 5

What are the three types of symbiotic relationships?

Answer 5

• Mutualism: both species benefit
• Commensalism: one benefits, the other is unaffected
• Parasitism: one benefits, the other is harmed

Question 6

Define:

Mutualism

Answer 6

A symbiotic relationship where both organisms benefit.

Example: Bees get nectar from flowers and carry pollen to help pollinate plants.

Question 7

Define:

Parasitism

Answer 7

A symbiotic relationship where one organism benefits and the other is harmed.

Example: Tapeworms live in larger organisms, taking nutrients from their intestines.

Question 8

Define:

Commensalism

Answer 8

When one organism benefits and the other is unaffected.

Example: Barnacles attach to whales and filter food from the water, while the whale is unaffected.

Question 9

What is the process of hunting to capture and eat organisms known as?

Answer 9

Predation

Question 10

What are the two common types of predators?

Answer 10

• Carnivores: Eat animals
• Omnivores: Eat both plants and animals

Question 11

What is herbivory?

Answer 11

A type of predation in which herbivores consume plant tissues.

Question 12

What is the difference between a predator and prey?

Answer 12

• Predator captures and eats another organism.
• Prey is the organism being captured and eaten.

Question 13

What are some examples of predator adaptations?

Answer 13

• Camouflage
• Offensive techniques

These adaptations help the predator be more effective in hunting and catching prey.

Question 14

What is one example of prey adaptation?

Answer 14

Include warning calls, camouflage, mimicry, or behaviors that help evade predators.

Example: Ground squirrels produce alarm calls.

Question 15

What is camouflage in predator-prey interactions?

Answer 15

The process of using body shape and coloration to blend in with the environment.

Question 16

What is mimicry in predator-prey interactions?

Answer 16

Whenever one species has evolved to resemble another species that is toxic or dangerous to predators.

Question 17

What is Batesian mimicry?

Answer 17

Occurs when an organism that is harmless mimics the warning coloration of a species that is harmful.

Question 18

What is Mullerian mimicry?

Answer 18

Occurs when two different species share the same warning coloration.

Question 19

What is warning coloration in predator-prey interactions?

Answer 19

Bright or distinctive coloration used by prey to warn potential predators of toxicity, unpalatability, or danger.

e.g., poison dart frogs

Question 20

What is coevolution in predator-prey interactions?

Answer 20

When the fitness of two different species is tightly linked, and these two species evolve in response to evolutionary changes in each other.

Question 21

What is interspecific competition?

Answer 21

The battle between two species for the same resources in an ecosystem.

Example: The Shenandoah salamander competing with the eastern red-backed salamander for habitat, leading to the Shenandoah salamander being designated as endangered.

Question 22

What is the Lotka-Volterra competition model?

Answer 22

A mathematical model that formalizes the impacts of interspecific competition on populations.

Question 23

What is intraspecific competition?

Answer 23

Competition between individuals from the same species.

Question 24

How does interspecific competition impact species’ survival?

Answer 24

It may lead to extinction: as less well-adapted species receive fewer resources, reducing their chances of survival.

Question 25

What are the **three basic types** of competition ecology?

Answer 25

* Interference competition * Exploitation competition * Apparent competition

Question 26

# Define: Interference competition

Answer 26

Involves direct interaction between species over a limited resource through **violence or aggressive behavior**.

Question 27

# Define: Exploitation competition

Answer 27

An indirect interaction between species over a limited resource where **one organism's use of resources depletes the total amount available to the other organism**.

Question 28

# Define: Apparent competition

Answer 28

A type of **indirect competition** where two species that do not share resources experience **population declines due to a shared predator** increasing in response to either species.

Question 29

What is the **competitive exclusion principle**? ## Footnote Also known as Gause's principle.

Answer 29

Two species competing for the **same limited resource cannot coexist indefinitely**; one will outcompete the other.

Question 30

What are the consequences of **competitive exclusion**?

Answer 30

The weak competitor may be excluded or extinct from the habitat.

Question 31

What is **niche differentiation**?

Answer 31

The process by which competing species exploit their environment differently in order to coexist.

Question 32

# Define: Fundamental niche

Answer 32

A theoretical niche that reflects all of the **ideal environments with no limiting factors** or competition in which a species may survive.

Question 33

# Define: Realized niche

Answer 33

The **actual conditions and area in which a species exists**, accounting for limiting factors such as competition and resource availability.

Question 34

What are **ecomorphs**?

Answer 34

Species or populations with **similar ecological roles and morphology** that evolved independently in similar environments.

Question 35

What are **keystone species**?

Answer 35

Organisms that other species in the ecosystem depend upon and whose disappearance would devastate their biological communities. ## Footnote Prairie dog - They dig tunnels that form prairie dog towns, providing homes for various animals and improving soil health for plant growth and insect habitat.

Question 36

If you were creating an assignment for your students to study keystone species, what **details** would you most likely have them research?

Answer 36

* Why is the organism they chose considered a keystone species? * What is its role in the ecosystem? * What is the importance to the ecosystem? * What are current threats to the species?

Question 37

What are some **sources** recommended for students to review before starting the assignment?

Answer 37

* World Wildlife Foundation (WWF) * National Geographic * Sources written by scientists, universities, or news outlets