Ecosystems

Question 1

What is a population?

Answer 1

-A population is a group of organisms of one species, living and interacting in the same area at the same time

Question 2

What is a community?

Answer 2

-A community is all of the populations of different species interacting with each other in an ecosystem

Question 3

What is a habitat?

Answer 3

-The place where a community of plants and animals lives

Question 4

What is an ecosystem?

Answer 4

-An ecosystem is a unit containing the community of organisms and their environment, interacting together

Question 5

What are abiotic factors?

Answer 5

Factors which are NON-LIVING:

• O2 availability
• Water availability
• Light intensity
• pH
• Pollution
• Temperature
• Minerals

Question 6

What are biotic factors?

Answer 6

Factors which are LIVING:

• Competition
• Disease
• Food supply
• Predation

Question 7

What are the 2 different types of competiton?

Answer 7

INTRAspecific:
-Competition b/t organisms of the SAME species

INTERspecfic:
-Competition b/t organisms of DIFFERENT species

Question 8

Describe the relationship b/t prey and predator population size?

Answer 8

• As the number of prey increases, so does the number of predators
• but there will be a time lag: the predator needs to respond to changes in availability of food
• As a result of increased predation, the prey numbers decrease so there is less food for the predators
• The number of predators then decreases, and so on.

Question 9

What is meant by the term “predation”?

Answer 9

The effect caused by a predator- a carnivore which kills and eats other animals

Question 10

What is meant by the term “Mutualism”?

Answer 10

This is a close relationship between two organisms of different species where both organisms benefit

Question 11

What is meant by the term “Parasitism”?

Answer 11

In this relationship, only one of the two organisms involved gains any benefit. The other is harmed

Question 12

At each successive stage in a food chain, what happens to the amount of biomass? Why?

Answer 12

The amount of biomass decreases:

• Some food is used for energy to move, respire, and maintain body temp
• Some of the material is not digested (e.g, plant roots)

Question 13

What are photosynthetic organisms?

Answer 13

The primary producers:

-They make up the most biomass in the system