Organisms Life What is life All living things

Organisms & Life

What is life?

All living things are composed of cells • Cell is the smallest unit of living matter • some living things are composed of a single cell others of collections of specialized cells • Multi-celled things can grow by duplicating cells - How does growth occur?

Living things have self regulating metabolisms • Various functions of a living things must work together, in cooperation for the thing to live - homeostasis (automatic tendency to maintain appropriate internal environment) • The mechanisms that accomplish this are called…homeostatic mechanisms

Living Things Move • If nothing else internal movement but… • Do plants move?

Respond to Stimuli • All living things respond to stimuli… • Changes in environment, fear, hunger, temperature, attraction, revulsion. . .

All things reproduce • All things die • species are perpetuated through reproduction • reproduction • reproduction

All living things adapt to their environment or. . .

Natural Selection • Charles Darwin and the HMS Beagle • The Origin of Species • …surmised that present forms of life have descended from previous forms of life…changes in form were a result of small changes being selected for by nature • Changes were selected because they allowed the species to be more successful. . .

IN ANY POPULATION, MEMBERS OF THE POPULATION DISPLAY SOME VARIATION FROM ONE ANOTHER

MORE ORGANISMS ARE BORN THAN SURVIVE TO REPRODUCE

RESOURCES ARE LIMITED, THEREFORE MEMBERS OF A POPULATION MUST COMPETE FOR SURVIVAL

SURVIVORS LIVE TO REPRODUCE AND PASS THEIR GENETIC CODE ON TO THE NEXT GENERATION

Life can be studied or viewed at different levels. . .

Next time. . . • Read Chapter 2 • Read Learning Objectives and Key Concepts • Science is a way of thinking pp 24 - 26 • Inductive/Deductive Logic p 27 • Scientific Method pp 27 - 32