Population size
- Growing population
- Population graphs
- Population regulation
- Concept of ecosystems
- Energy in ecosystem
- Ecological pyramids
, Growing population
Population numbers fluctuate and this is dependent on
various factors including birth and death rates,
immigration, and emigration. Birth and immigration
increase population size, death and emigration decrease
population size.
(Birth + immigration) - (deaths + emigration) =
population size
Lag – period of adaptation, preparation for growth,
enzyme synthesis.
Exponential growth – no factors limiting reproducing but
environment resistance will set in. The cells can divide at
a constant rate with population doubling per time unit.
Deceleration/stationary – number of new individuals
produced equals the death rate. Certain factors limiting
population. He population has reached it carrying
capacity for a particular environment.