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Facts About Facts About Living ThingsLiving Things

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What Are the Main What Are the Main Characteristics of Characteristics of

organisms?organisms?1. Made of CELLS2. REPRODUCE 3. Have a UNIVERSAL GENETIC CODE 4. GROW and DEVELOP 5. Require ENERGY (food) and EXCHANGE

materials with surroundings (water, wastes, gases)

6. Respond to their ENVIRONMENT7. Maintain a STABLE ENVIRONMENT

-Homeostasis

8. Living things CHANGE OVER TIME.

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Living things are organized…

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LEVELS OF ORGANIZATIONLEVELS OF ORGANIZATION

Nonliving Levels:

1.ATOM (element)

2.MOLECULE (compounds like

carbohydrates & proteins)

3.ORGANELLES (nucleus, ER, Golgi

…)

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LEVELS OF ORGANIZATIONLEVELS OF ORGANIZATION

Living Levels:

1.CELL (makes up ALL organisms)

2.TISSUE (cells working together

3.ORGAN (heart, brain, stomach …)

4.ORGAN SYSTEMS (respiratory, circulatory

…)

5.ORGANISM

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Number of CellsNumber of CellsAlthough ALL living things are

made of cells, organisms may be:

• Unicellular – composed of one cell

• Multicellular- composed of many cells that may organize into tissues, etc.

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Multicellular OrganismsMulticellular Organisms• Cells in multicellular organisms

often specialize (take on different shapes & functions)

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Cell SpecializationCell Specialization

•Cells in a multi-cellular organism become specialized by turning different genes on and off

•This is known as DIFFERENTIATION

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Specialized Animal CellsMuscle cells Red blood cells

Cheek cells

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Specialized Plant cells

Xylem cellsPollen

Guard Cells

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Organization Organization Levels of LifeLevels of Life

Atoms to OrganismsAtoms to Organisms

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ATOMS MOLECULES ORGANELLES

Nonliving LevelsNonliving Levels

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CELLS – life starts here

TISSUES – Similar cells working together

Living LevelsLiving Levels

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ORGANSORGAN SYSTEMS ORGANISM

Different tissuesworking together

Different organsworking together

More Living LevelsMore Living Levels

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To do…1. Please read pages 15 -17, and answer

questions # 1, 4, 5 and 6 on page 22

2. Please read pages 190-193. While reading, complete the accompanying worksheet.