This document outlines the key characteristics that define living things and distinguishes them from nonliving things. It identifies eight life functions or processes that classify something as living: 1) digestion, 2) circulation, 3) movement, 4) respiration, 5) excretion, 6) coordination, 7) reproduction, and 8) immunity. These life functions work together to maintain homeostasis, an organism's ability to keep a stable internal environment, through various control mechanisms.

1. “Living” Vs. “Nonliving” What makes something “alive”?

2. Biology Bios + logos “ Life” “Study” Biology – study of living things, or, organisms .

3. Life Functions 8 life functions/processes that classify something as “living”, or an organism : 1. Digestion 5. Excretion 2. Circulation 6. Coordination 3. Movement 7. Reproduction 4. Respiration 8. Immunity

4. 1. Digestion Breaking down large food molecules to smaller molecules. - small molecules can enter cells. ex: glucose

5. 2. Circulation Transport of materials within an organism. - brings glucose and oxygen to cells (mailman). - takes away wastes and carbon dioxide from cells. (garbage man)

6. 3. Movement Voluntary change in position of organism. - muscular and skeletal systems work together.

7. 4. Respiration Uses oxygen to change glucose into energy (ATP).

8. 5. Ex cretion “ Ex” = out! Removal of waste products! - sweat, urine, carbon dioxide

9. 6. Coordination Nervous system and endocrine system send chemical messages throughout the body. - hormones are chemical messages.

10. 7. Reproduction Ability of an organism to make more of its own kind. - necessary for survival of species . Sexual Reproduction – involves two parents. Asexual Reproduction – involves one parent.

11. 8. Immunity Ability of an organism to fight disease and foreign invaders. - produce antibodies and white blood cells.

14. Homeostasis All life processes work together in order to ensure maintenance of homeostasis . Homeostasis – an organism’s ability to keep a stable internal environment (steady-state). - any change in a life process = bad for homeostasis. - organisms have control mechanisms to help maintain homeostasis.

15. Example of Control Mechanism 1. Temp. rises  2. Sweating  3. Cools body back down to normal temp (98.6).