B I O L O G Y

ORGANISMS AND THEIR ENVIRONMENT

• Ecology – study of interactions that take place between organisms and their environment

• Abiotic factors – nonliving parts of an organism’s environment• Sunlight, rain, temperature, soil type

• Biotic factor – living organism• Fish, bacteria, bird, human, butterfly

LEVELS OF ORGANIZATION PAGE 40 IN YOUR BOOK

• Organism – one living organism• Population – group of organisms of the

same species that interbreed and live in the same area at the same time

• Biological community – interacting populations in an area at a certain time

• Ecosystem – interacting populations of in a biological community AND the community’s abiotic factors

• Biosphere – The portion of the Earth that supports life

HABITAT VS. NICHE

• Habitat – the PLACE where an organism lives out its life (the WHERE it lives)

• Niche – all the strategies and adaptations a species uses in its environment (the HOW it lives)

SYMBIOSIS

• Symbiosis – a relationship between 2 organisms of different species

• Mutualism – a relationship in which BOTH species benefit• Ants and Acacia trees – the ants

protect the tree by attacking any animal trying to feed on the tree, the tree provides nectar and a home for the ants

• Commensalism – a relationship in which one species benefits and the other is not harmed or benefited • Spanish moss grows on the branches

of trees. The moss has a place to live and the tree is not harmed.

• Parasitism – one species benefits while harming the other species• A flea feeds on your pet dog which

harms the dog but provides a habitat for the fleas.