4.2-4.3 - niche & succession

Question 1

Why do organisms live in different places?

Answer 1

Each species has a range of conditions under which it can grow and reproduce

Question 2

What is where an organism lives called?

Answer 2

habitat
*determines by a species’ tolerance for environmental conditions

Question 3

What is the niche?

Answer 3

the range of physical and biological conditions in which a species lives and the way the species obtains what it needs to survive and reproduce.

Question 4

What is the first factor determining where organisms can form communities?

Answer 4

resources - essential for survival

Question 5

What is the second factor determining where organisms can form communities?

Answer 5

physical aspects - abiotic factors an organism requires for survival

Question 6

What is the third factor determining where organisms can form communities?

Answer 6

biological aspects - biotic factors an organism requires for survival

Question 7

When is competition created?

Answer 7

when organisms attempt to use the same resources in the same place at the same time

Question 8

What happens when different species attempt to use different resources at the same time?

Answer 8

There will always be a winner and a loser. The less competitive species does not survive. No 2 species can occupy exactly the same niche in exactly the same habitat at exactly the same time.

Question 9

What is the principle that the less competitive species will not survive and no 2 species can occupy the same niche at exactly the same time called?

Answer 9

competitive exclusion principle

Question 10

Rather than compete for resources, some species will…

Answer 10

divide them

Question 11

What it it called when one animal hunts, captures, and feeds off another species?

Answer 11

predation

Question 12

What is the potential impact of predation?

Answer 12

It can effect the size of prey in populations in a community and determine the places they live and feed.

Question 13

What is a keystone species?

Answer 13

By altering the population of one species, it could dramatically impact the structure of an entire community.

Question 14

What is it called when an animal feeds off primary producers?

Answer 14

herbivory

Question 15

What is the potential impact of herbivory organisms?

Answer 15

Herbivores can effect both the size and distribution of plant populations in a community and determine the places that certain plants can survive and grow

Question 16

What is symbiosis (“living together”)?

Answer 16

It is any relationship in which two species live closely together.

Question 17

What is mutualism?

Answer 17

A relationship in which both species benefit

Question 18

What is parasitism (hint: parasite)?

Answer 18

a relationship in which one organism lives inside or on another organism and harms it

Question 19

What is commensalism?

Answer 19

A relationship in which one organism benefits and the other is neither helped nor harmed.

Question 20

What is geological succession?

Answer 20

A series of more-or-less predictable changes that occur in a community over time.

Question 21

Why does succession occur?

Answer 21

Ecosystems change over time, especially after disturbances, as some special die out and new species move in.

Question 22

What is primary succession?

Answer 22

Succession that occurs when no remnants of community remains

Question 23

What is an example of primary succession?

Answer 23

A volcanic explosion - can create new land or sterilize existing areas over the years.

Question 24

What is a pioneer species? (Ex. lichen)

Answer 24

the first species to colonize a barren region

Question 25

What is secondary succession?

Answer 25

Succession in which the entire community is not destroyed. Secondary succession proceeds faster than primary succession.

Question 26

What does secondary succession usually occur after?

Answer 26

Wildfires, hurricanes, or other natural disturbances; human activity (logging or farming)

Question 27

Why does secondary succession have a faster recovery time?

Answer 27

The soil survives the disturbances and the disturbance itself can provide the proper environment for growth (stimulate needs to germinate)

Question 28

What are climax communities?

Answer 28

communities in which populations remain uniform and stable with one another and with their environment: end result of succession.

Question 29

Does succession always bring back the climax community to its original status?

Answer 29

In healthy ecosystems, secondary succession following natural disturbances often reproduces the original climax community, but others are not uniform in areas where there are multiple disturbances or where human-caused disturbances have occurred.