Abundance & Distribution of Organisms

Question 1

What is abundance?

Answer 1

The number of individuals of a single species in an

ecosystem / habitat = population size

Question 2

What is distribution?

Answer 2

Distribution: Where the species are found in an ecosystem / habitat

Question 3

What is abundance of organisms?

Answer 3

intraspecific competition

• competition within a species
• they occupy the same niche - compete for everything e.g. food, mates

carrying capacity -

• the max. stable population an ecosystem can maintain
• vary with biotic and abiotic factors

limiting factor - the thing that limits population size
e.g. competition for food - biotic and abitoic - resting sites

Question 4

What is interspecific competition?

Answer 4

• competition between species
• abundance of one species will affect the other
• species with a similar niche will compete for resources

Question 5

What are abiotic factors in abundance and distribution of organisms?

Answer 5

• species can tolerate a range of conditions
• where conditions are optimal, population size will be bigger e.g. altitude - tree line - where abiotic factors
  is going to prevent trees growing above that level

Question 6

What is distribution in more detail?

Answer 6

• interspecific competition and predation
  will affect an organism’s distribution
• organisms will only exist where they can survive