5A3 Biotic vs Abiotic Factors

Question 1

What are limiting factors in ecology?

Answer 1

Anything that keeps a population from continuing to grow within an ecosystem.

• Physical factors
• Biological factors
• Density-independent factors
• Density-dependent factors

Question 2

How do limiting factors most affect population size?

Answer 2

Population numbers in an ecosystem rise and fall in response to changes in limiting factors.

When there are few limiting factors, the population grows.

When there are many limiting factors, the population declines.

Question 3

What are physical factors as limiting factors?

Answer 3

• Temperature
• Water
• Oxygen
• Light

Question 4

What are biological factors as limiting factors?

Answer 4

• Predation
• Competition
• Parasitism
• Disease

Question 5

What are density-independent factors as limiting factors?

Answer 5

• Natural disasters
• Climate change
• Extreme weather events

Pollution may also act as a density-independent factor.

These limiting factors are not influenced by how many organisms inhabit an area.

Question 6

What are density-dependent factors as limiting factors?

Answer 6

• Disease
• Resource availability

Density dependent factors are influenced by how many organisms inhabit an area.

These limiting factors depend on population size.

Question 7

How are limiting factors related to carrying capacity?

Answer 7

They influence the carrying capacity of a population.

The more available resources, the larger the population an ecosystem can support.

Question 8

What is the carrying capacity of a population?

Answer 8

The maximum number of individuals of a species an environment can sustainably support.

Question 9

How can food and water limit population growth?

Answer 9

• Sufficient resources lead to population growth.
• Scarcity leads to population decline.

Question 10

What are the two types of limiting factors to population growth?

Answer 10

• Biotic factors
• Abiotic factors

Question 11

What are examples of biotic limiting factors?

Answer 11

Plants and animals as food sources.

Question 12

What are examples of abiotic limiting factors?

Answer 12

Physical factors such as temperature and water resources.

Question 13

What is an ecosystem?

Answer 13

The interaction between all of the biotic (living) and abiotic (non-living) factors within a geographic area.

Question 14

What is a habitat?

Answer 14

The natural home or place within an ecosystem that provides the kind of food, water, shelter, and living space an organism needs to survive.

Question 15

What is a niche?

Answer 15

The special role an organism plays within its ecosystem.

Question 16

What determines the niche of an animal within its ecosystem?

Answer 16

Feeding habits and other adaptations.

Question 17

How do niches contribute to minimal competition within an ecosystem?

Answer 17

Different species of organisms do not typically ever occupy the same niche within their ecosystem, reducing competition for the same resources.

Question 18

Explain the relationship between ecosystems, habitats, and niches.

Answer 18

• Ecosystems are the interaction between biotic and abiotic factors.
• Habitats are suitable places for organisms.
• Niches are the specific roles organisms play.

Question 19

What is a population in biology?

Answer 19

A group of organisms of the same species living within an area.

Question 20

Why are abiotic factors important to an ecosystem?

Answer 20

Abiotic factors contribute to the habitat of an organism. The availability of abiotic factors contributes to the availability of many resources organisms rely on to survive.

Question 21

Does the picture depict a biotic factor or an abiotic factor?

Answer 21

Abiotic factor

Sunlight and water are not living organisms.

Question 22

Does the picture depict a biotic factor or an abiotic factor?

Answer 22

Biotic factor

Plants are living organisms.

Question 23

Does the picture depict a biotic factor or an abiotic factor?

Answer 23

Biotic factor

Dolphins are living organisms.

Question 24

Does the picture depict a biotic factor or an abiotic factor?

Answer 24

Abiotic factor

Rocks are not living organisms.

Question 25

How do **abiotic factors** like temperature and sunlight influence the distribution of **biotic factors** in an ecosystem?

Answer 25

Abiotic factors like **temperature and sunlight** determine which organisms can survive in an environment. ## Footnote Organisms must be **adapted** to these conditions to thrive.

Question 26

How are current shifts in abiotic factors **influencing** Earth's ecosystems?

Answer 26

Changes like rising temperatures from global warming are leading to **drought, extreme weather, and warmer water**. Organisms not adapted to these conditions may **struggle to survive**.

Question 27

How do **human activities** impact the balance between biotic and abiotic factors in ecosystems?

Answer 27

Human activities contribute to a **degradation** of abiotic factors in ecosystems due to infrastructure development and pollution.

Question 28

How do abiotic factors influence the **reproductive strategies** of biotic factors in different ecosystems?

Answer 28

Abiotic factors affect when and where **resources are available**. Organisms adapt their reproductive timing to ensure offspring are born when conditions **support survival**.

Question 29

What is an example of how biotic factors can **modify** abiotic factors in an ecosystem?

Answer 29

Beavers build dams in streams which may redirect water flow to areas of an ecosystem where water was not previously flowing.