PPT #1: Criteria of life? Why is biodiversity so important? Ecology PPT #1: Criteria of life? Why is biodiversity so important?

Guiding Question: how does the flow of energy and matter between populations in an ecosystem help determine the size of a given ecosystem?

Define Ecology The study of interactions between organisms and their environment. Addresses the full scale of life – from tiny bacteria to multi-celled organisms and process that span the entire Earth

Life – how do we define it? Scientists have 7 criteria that they agree something must meet to be considered ‘living’

#1 All organisms are made of cells Cells are the basic unit of life

#2 All organisms need energy Living organisms need energy in the form of ATP to perform life functions

#3 All organisms respond to their environment Organisms react to changes in their environment

#4 All organisms reproduce Organisms must make more of themselves, either by sexual or asexual means ll

#5 All organisms grow and develop Organisms get bigger (grow) and often more complex (develop) as they get older

#6 All organisms carry DNA Organisms inherit traits from their parents

#7 All organisms maintain homeostasis Living organisms must maintain stable internal conditions Internal temperature Blood pressure Fluids and blood sugar

Biodiversity: what is it? The number and variation of living organisms, both plant and animal, found in a given area

Why is biodiversity so important? Cal Academy of Science Video

Two key terms Variation: a different or distinct form of something

Adaptation: a change in an organism that helps it to survive and reproduce in its environment