HOW TO DEFINE LIFE

1. HOW TO DEFINE LIFE

2. Is Ebola a living thing? Most people have heard of Ebola – a deadly VIRUS that is affecting people in parts of Africa. Viruses: Have DNA..... but no cellular structure Can reproduce.....but only with a host Use energy.... but this comes from the host cell’s machinery So....is the Ebola virus a living thing? What do you think?

3. How do you know something is alive? • Biology means the study of (-ology) all life (bio-) and includes many branches

4. How do you know something is alive? • Biologists organize living things into kingdoms. There are currently six kingdoms.

5. How do you know something is alive?

6. CHARACTERISTICS OF LIFE & LIFE PROCESSES • ORGANIZATION • The level of complexity • All living things need six essential elements: Carbon, Hydrogen, Nitrogen, Oxygen, Phosphorus, and Sulfur (CHNOPS) • All living things are made cells • One-celled organism - unicellular • Many-celled organism - multicellular

7. CHARACTERISTICS OF LIFE & LIFE PROCESSES • ENERGY USE • Organisms need energy constantly to build molecules (synthesis) and cell and to break down (digest) substances (such as breaking down food for nutrition)

8. Fill It In … • Synthesis means …. • Visual:

9. CHARACTERISTICS OF LIFE & LIFE PROCESSES • ENERGY USE • Organisms must transportnutrients to be used in cellular respiration to produce energy

10. CHARACTERISTICS OF LIFE & LIFE PROCESSES • ENERGY USE • An organism’s chemical reactions are called its metabolism

11. CHARACTERISTICS OF LIFE & LIFE PROCESSES • REPRODUCTION • An organism must replace themselves so the entire species will survive

12. CHARACTERISTICS OF LIFE & LIFE PROCESSES • REPRODUCTION • May be asexual (only one individual contributes genetic material) or sexual (two individuals contribute genes)

13. CHARACTERISTICS OF LIFE & LIFE PROCESSES • GROWTH & DEVELOPMENT • Growth - to increase in size. Increases the number of cells of a multicellular organism • Development - change that takes place in structure and function of an organism during its life cycle. Example: embryo becomes a fetus

14. CHARACTERISTICS OF LIFE & LIFE PROCESSES • RESPOND TO STIMULI • A quick, non-permanentchange • Stimulus - anything that causes an organism to react Example: a loud noise (stimulus) causes your dog to run under the bed (response)

15. CHARACTERISTICS OF LIFE & LIFE PROCESSES • ADJUST TO ENVIRONMENT • Homeostasis - the regulationof an organism’s internal environment to maintain conditions for life • Ex: Getting rid of wastes byexcretion

16. CHARACTERISTICS OF LIFE & LIFE PROCESSES • ADJUST TO ENVIRONMENT • An adaptation is an inherited structure, behavior, or internal process that enables organisms to better survive an environment • Ex: Gills on a fish

17. Fill It In … • Life Processes: (things you do) • S- • T- • E- • R- • N- • G- • R- • R-

18. Fill It In … • Life Processes: (things you do) • S- synthesis • T- transport • E- excretion • R- regulation • N- nutrition • G- growth & development • R- reproduce • R- respond to stimuli

19. Something extra … • Characteristics of Life: (things you have) • C- • H- • R- • E- • G- • L- • E- • R-

20. Something extra … • Characteristics of Life: (things you have) • C- cells • H- homeostasis • R- reproduction • E- energy • G- genetic material (DNA) • L- levels of organization • E- evolve • R- respiration

21. Check Yourself! • What is the basic unit of life? • A group of cells that perform a similar function are known as a ___________. • What are two reasons an organism needs energy? • Label the following an an adaptation or a response to a stimulus • The hollow bones of a bird __________________ • Jerking your hand away from a hot stove ___________________

22. Check Yourself! • What is the basic unit of life? CELL • A group of cells that perform a similar function are known as a ___________. • What are two reasons an organism needs energy? • Label the following an an adaptation or a response to a stimulus • The hollow bones of a bird __________________ • Jerking your hand away from a hot stove ___________________

23. Check Yourself! • What is the basic unit of life? CELL • A group of cells that perform a similar function are known as a _TISSUE_. • What are two reasons an organism needs energy? • Label the following an an adaptation or a response to a stimulus • The hollow bones of a bird __________________ • Jerking your hand away from a hot stove ___________________

24. Check Yourself! • What is the basic unit of life? CELL • A group of cells that perform a similar function are known as a _TISSUE_. • What are two reasons an organism needs energy? SYTHESIS, DIGESTION, TRANSPORT, METABOLISM • Label the following an an adaptation or a response to a stimulus • The hollow bones of a bird __________________ • Jerking your hand away from a hot stove ___________________

25. Check Yourself! • What is the basic unit of life? CELL • A group of cells that perform a similar function are known as a _TISSUE_. • What are two reasons an organism needs energy? SYTHESIS, DIGESTION, TRANSPORT, METABOLISM • Label the following an an adaptation or a response to a stimulus • The hollow bones of a bird ADAPTATION_ • Jerking your hand away from a hot stove ___________________

26. Check Yourself! • What is the basic unit of life? CELL • A group of cells that perform a similar function are known as a _TISSUE_. • What are two reasons an organism needs energy? SYTHESIS, DIGESTION, TRANSPORT, METABOLISM • Label the following an an adaptation or a response to a stimulus • The hollow bones of a bird ADAPTATION_ • Jerking your hand away from a hot stove _RESPONSE TO STIMULUS__