B4.2 Ecological niches

Question 1

Heterotrophic

Answer 1

Organisms consume carbon compounds from other organisms

Question 2

Holozoic nutrition

Answer 2

Internal digestion

Question 3

Autotrophic

Answer 3

Organisms which produce their own carbon compounds

Question 4

Saprotrophic nutrition

Answer 4

External digestion via releasing enzymes

Question 5

Obligate anaerobe

Answer 5

Organisms which can only survive in the absence of oxygen

Question 6

Obligate aerobe

Answer 6

Organisms which can only survive in the presence of oxygen

Question 7

Phytochemicals

Answer 7

Toxic chemicals secreted by plants to avoid predation

Question 8

Chemotrophs

Answer 8

Obtain nutrition via oxidation of inorganic molecules, such as iron and magnesium

Question 9

Fundamental niche

Answer 9

Range of environmental conditions in which an organism can survive and reproduce

Question 10

Realized/”actual” niche

Answer 10

Niche in which the organism is the best adapted to live and coexist with other niches

Question 11

Competition exclusion principle

Answer 11

If two species in the same niche compete - the weaker will become extinct

Question 12

Niche partioning

Answer 12

Process by which different species utilize the environment in different ways - aiding in coexistence.

Question 13

Detrivores

Answer 13

Decomposers obtaining nutrition via internal digestions

Question 14

Biomass

Answer 14

Total mass of organism (without water)

Question 15

Gross primary production (GPP)

Answer 15

Total amount of energy captured as biomass by primary producers

Question 16

Net primary production (NPP)

Answer 16

Total amount of energy that remains after losses
NPP = GPP - R
R = respiration losses