Module 2: Dynamic Ecosystems

Question 1

Biosphere

Answer 1

The parts of the earth and surrounding atmosphere where life exists

Question 2

Carrying capacity

Answer 2

The largest number of individuals of one species that an ecosystem can support over time.

Question 3

Community

Answer 3

All the populations living in an ecosystem at the same time

Question 4

Ecosystem

Answer 4

All the living and nonliving things in a given area.

Question 5

Limiting factor

Answer 5

A factor that can limit the growth of the population

Question 6

Overpopulation

Answer 6

A condition that occurs when a population becomes so large that it causes damage to the environment.

Question 7

Population

Answer 7

All the organisms of the same species that live in the same area at the same time.

Question 8

Species

Answer 8

A group of organisms that have similar traits, are able to reproduce, and their offspring is fertile.

Question 9

Symbiosis

Answer 9

A close, long-term relationship between two species that usually involves an exchange of food or energy.

Question 10

Commensalism

Answer 10

A symbiotic relationship that benefits one species but does not harm or benefit the other.

Question 11

Mutualism

Answer 11

A symbiotic relationship where both organisms benefit

Question 12

Parasitism

Answer 12

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

Question 13

Ecological succession

Answer 13

The process of one ecological community gradually changing into another

Question 14

Climax community

Answer 14

A stable community that no longer goes through major ecological changes.

Question 15

Eutrophication

Answer 15

The process of a body of water becoming nutrient rich.

Question 16

Dynamic equilibrium

Answer 16

Describes the balance between different parts of the ecosystem.

Question 17

What are examples of limiting factors

Answer 17

Space, food, water, mates, sunlight, and temperature

Question 18

Extinction

Answer 18

a species that has died out and there are no individuals left. It can be caused by predation, natural disasters, or damage to the environment.

Question 19

Endangered species

Answer 19

a species whose population is at risk of extinction. There are approximately 16,000 species that are currently categorized as endangered. If their numbers fall further they are then considered critically endangered.

Question 20

Threatened species

Answer 20

this is a species that is at risk but not yet endangered. There are approximately 7,000 species on earth currently classified as threatened.

Question 21

What is a cooperative relationship and some examples

Answer 21

a group of the same species working together for the common good and benefit of the group. This could be for protection, food, watching for danger, and raising young. For example: leaf cutter ants working together to cut leaves and grow the fungus they need for food, Elephants living in herds and sharing routes to watering holes from one generation to the next, meerkats taking turns to be “on look out” for prey so everyone can hide if a predator comes.

Question 22

What are predator-prey relationships

Answer 22

The process by which one organism hunts and eats another organism. This provides the predator with food, as well as preventing the population of the prey animal from getting too large for its habitat.

Question 23

What are competitive relationships

Answer 23

organisms sharing the same habitat competing for resources such as space, sunlight, water and food.

Question 24

What is primary succession

Answer 24

Ecological succession in new areas of land with little or no soil or vegetation. For example: lava flow, sand dune, or exposed rock.

Question 25

What is secondary succession

Answer 25

Ecological succession in areas where existing ecosystems have been disturbed or destroyed. For example: forest land that was cleared by early colonists for farming but was not planted with crops, this land gradually grew back into a forest community.

Question 26

What causes change in aquatic ecosystems

Answer 26

Aquatic ecosystems are impacted by rainfall, temperature, runoff, sediment build up, human activity, and water pathways being blocked (such as a tree falling on a small stream).

Question 27

What are the effect of changing ecosystems on populations

Answer 27

Sudden disruptions such as forest fires, or floods, can make it extremely difficult for organisms to adapt to the new ecosystem. Gradual changes, such as mountain formation, can sometimes have benefits. Disturbances can also control the size of a population or allow new growth of plant life.

Question 28

What are natural disruptions

Answer 28

Forest fires
Floods
Volcanic eruption
Disease
Mountain formation

Question 29

What are unnatural (mostly human) disruption

Answer 29

Resource extraction
Pollution
Nonnative species.