Environmental Science

Chapter 1 Section 3

Interactions

All living things interact with their environment both biotic and abiotic

Most living things produce more offspring than can survive

Limiting Factors

Most living things produce more offspring than can survivePopulations cannot grow indefinitelyThe population can only be as big as the resources will allowThe environment contains a finite amount of food, water, living spaceThese factors are limiting factors because any one of these factors can limit the size of the population

Carrying Capacity

The largest population that can be supported in a given environment

When a population grows larger than its carrying capacity, limiting factors in the environment cause the population to decrease.

Interactions Among Organisms

Four main ways that species interact with one another Competition Predator/prey Symbiosis coevolution

Competition

Can occur within populations and within communities

Organisms try to use the same resources

Coevolution

Long-term change that takes place in two species because of their interactions with one another.

Predator/Prey

Prey - organism that gets eaten

Predator – organism that eats the prey

Both predators and prey adapt in response to one another in order to survive

Symbiosis

Close long-term relationship between different species in which at least one species benefits 3 types

Mutualism – both species benefits – ex coral and algae Commensalism – one species benefits, the other is

unaffected – ex sharks and remoras Parasitism – one species benefits, the other is harmed

Parasite – the organism that benefits Host – the organism that is harmed Ex- deer tick is parasite, deer is host