CELL THEORY GENERAL CHARACTERISTICS of all CELLS ---------------------------------------------

CELL BASIC UNIT OF STRUCTURE AND FUNCTION IN ORGANISMS SMALLEST UNIT THAT CAN CARRY ON ALL LIFE PROCESSES TWO TYPES: PROKARYOTIC EUKARYOTIC

CELL HISTORY ROBERT HOOKE: 1665 Examined cork tissue saw small open spaces that resembled small rooms, called them “CELLS”

1670 ‘FIRST’ MICROSCOPE ANTON VON LEEUWENHOEK Observed first living cells in water he called “wee beasties”. They later became the Protists.

All organisms composed of cells? SCHLEIDEN 1838: Botanist Hypothesized all plant tissue made of cells SCHWANN 1834: Zoologist Hypothesized all animal tissue made of cells

"omnis cellula e cellula” RUDOLF VIRCHOW, 1855 "omnis cellula e cellula” DOCTOR STUDIED BACTERIA CELLS DIVIDING AND HYPOTHESIZED THAT ALL “CELLS COME FROM OTHER CELLS” BECAME KNOWN AS BIOGENESIS, REPLACED THE WIDELY HELD IDEA OF SPONTANEOUS GENERATION, NOTION THAT NON-LIVING THINGS COULD GIVE RISE TO LIVING ORGANISMS

CELL THEORY General Tenants ALL LIVING ORGANISMS ARE COMPOSED OF 1 OR MORE CELLS CELLS ARE BASIC UNIT OF STRUCTURE AND FUNCTION IN LIVING SYSTEMS ALL CELLS COME FROM PREEXISTING CELLS BEACH BALL

Modern Tenants of Cell Theory All cells contain hereditary information which is passed from cell to cell during cell division. All cells are basically the same chemical composition.(PROTEINS, LIPIDS, CARBOHYDRATES, NUCLEIC ACIDS) All energy flow(metabolism/biochemistry) of life occurs within the cell.

CELL DIVERSITY ORGANIZATION UNICELLULAR MULTICELLULAR ONE CELL PROTISTS BACTERIA YEAST MANY CELLS Colonial Protists MOST FUNGI ALL ANIMALS AND PLANTS

NO MEMBRANE BOUND ORGANELLES CELL TYPE PROKARYOTIC EUKARYOTIC NO NUCLEUS NUCLEUS NO MEMBRANE BOUND ORGANELLES MEMBRANE BOUND ORGANELLES BINARY FISSION MITOSIS BACTERIA ONLY ALL OTHER ORGANISMS

ENERGY AUTOTROPHIC PRODUCERS HETEROTROPHIC SAPROPHYTES CONSUMERS CAN CONVERT ENERGY FROM SUN OR CHEMICALS INTO A FORM OTHER ORGANISMS CAN USE PRODUCERS PHOTOSYNTHETIC PLANTS PROTISTS BACTERIA CHEMOSYNTHETIC BACTERIA HETEROTROPHIC MUST OBTAIN ENERGY FROM AUTOTROPHS OR OTHER HETEROTROPHS SAPROPHYTES ABSORB NUTRIENT FROM DECAYING ORGANIC MATTER FUNGI CONSUMERS HERBIVORES OMNIVORES CARNIVORES EUBACTERIA ARCHAEBACTERIA

CELL STRUCTURE FORM FITS FUNCTION The shape of a cell is directly related to the job that it performs.

BONE OSTEON STRENGTH, SUPPORT, INFLEXIBLE, CELLS ARE LAYERED LIKE RINGS ON TREE. LONG CYLINDERS FOR SUPPORT

MUSCLE SKELETAL FLEXIBLE, ELASTIC, ALLOW MOVEMENT CELLS CLUSTERED INTO CORD-LIKE BUNDLES

HAVE STRUCTURES TO RECEIVE AND TRANSMIT INFORMATION NERVE NEURONS LONGEST IN THE BODY HAVE STRUCTURES TO RECEIVE AND TRANSMIT INFORMATION

SKIN EPITHELIAL CELLS BARRIER, PROTECTION CELLS ARE SPHERICAL TIGHTLY PACKED INTO TISSUE LAYERS

CELL SIZE SMALLEST CELLS BACTERIA LARGEST CELLS OSTRICH EGGS

THE SIZE OF A CELL IS RELATED TO ITS ABILITY TO MOVE MATERIALS EFFICIENTLY AS CELLS GROW VOLUME INCREASES FASTER THAN SURFACE AREA

MOST MATERIALS ENTER AND LEAVE A CELL VIA PASSIVE TRANSPORT LARGE CELLS CANNOT MOVE MATERIALS EFFECTIVELY VIA DIFFUSION OR OSMOSIS SMALLER THE CELL THE FASTER MATERIALS CAN ENTER AND LEAVE A SMALL CELL IS AN EFFICIENT CELL!