Fall Semester Exam Review #3 (Unit 4)

Question 1

What are some negative effects of human impact on ecosystems? (give at least three)

Answer 1

Mining: strips land of plants and also disrupts animals

overfishing: taking too many fish from an ecosystem that can be replenished and impacting entire food webs

deforestation- removal of trees that limits habitats and displaces animals

Question 2

What is biodiversity

Answer 2

the # and variety of organisms found in a specific region

Question 3

Why is biodiversity important

Answer 3

The high the biodiversity of an ecosystem is, the more stable it can remain through a natural disaster

Question 4

What is sustainability

Answer 4

an ecosystem that can remian diverse and productive over time without outside influence or assistance

Question 5

Why are non-native species so dangerous to ecosystems

Answer 5

Non-native species often do not have natural predators and so their populations often grow unchecked.

An example of this is in the Everglades and the Burmese phythones that were released there. These snakes are not native and have no natural predators and are damaging the Everglades ecosystem by taking away resources from native animals

Question 6

What is primary succession

Answer 6

the establishment of a community in an area of bare rock or sand, where NO topsoil is present

Question 7

What is secondary succession

Answer 7

orderly change that occures in a plce where soil remains

Question 8

Which is faster and why

primary or secondary succession

Answer 8

secondary because the lichen stage is not necessary since the soil is already present

Question 9

what are some causes of primary sucession

Answer 9

glacier moving
volcano
rock slides

Question 10

what are some causes of secondary succession

Answer 10

fires
floods
storm surges
mudlsides

Question 11

Pioneer stages of primary succession

Answer 11

1st- lichens

2nd- mosses and ferns

3rd- herbs and weeds

Question 12

intermediate stages of primary succession

Answer 12

4th- grasses

5th- shrubs

6th- shade intolerant trees

Question 13

climax community of primary succession

Answer 13

7th- shade tolerant trees

Question 14

Pioneer stages of secondary succession

Answer 14

1st- annual plants

2nd- grasses and herbs

Question 15

Intermediate stages of secondary succession

Answer 15

3rd- shrubs

4th- pines

5th- young oak/hickory

6th- pines die, oak/hickory mature

Question 16

Climax community of secondary succession

Answer 16

7th- mature oak/hickory forest

Question 17

What are limiting factos in an ecosystem

Answer 17

Any factor that limits a population

Question 18

What are the main types of limiting factors

Answer 18

food
water
shelter

Question 19

What is competition

Answer 19

Organisms that are competing for resources such as food, water, mates, shelter

Question 20

What are pioneer species

Answer 20

the 1st species that colonizes new or undisturbed land

Question 21

What are the pioneer species in primary succession

Answer 21

lichen and moss

Question 22

What are the pioneer species in secondary succession

Answer 22

annual plants + some grasses

Question 23

What is beginning source of energy for all life

Answer 23

Sun