1. C ELLS

2. I. T HE CELL THEORY Schleiden and Schwann – 1838 1. All living things are made up of cells. (Unit of STRUCTURE) 2. The cell is the unit of FUNCTION of living things (Living things carry out life functions because of the activities of their cells). Virchow – 1855 3. All cells come from other pre-existing cells.

3. II. O RGANIZATION OF C ELLS Cell  Tissue  Organ  Organ System  Organism

4. III. C ELL STRUCTURE Cells contain many different structures called ORGANELLES (little organs) Each Organelle performs a special function (job) within the cell.

5. O RGANELLES 1. Cell membrane (Animal & Plant cells) Controls what moves into and out of the cell (semi – permeable) 2. Cytoplasm (Animal & Plant cells) Fluid that contains the cell parts (Cyclosis – the way the cytoplasm flows around the cell in a circular motion)

6. 3. Nucleus (Animal & Plant cells) Controls all cell activities (Control center) 4. Nuclear membrane (Animal and Plant cells) Controls what moves in and out of the nucleus 5. Nucleolus (Animal and Plant cells) Round structure located inside nucleus Helps make ribosomes

7. 6. Chromosomes (Animal and Plant cells) “Colored bodies” located in the nucleus that carry information to determine traits (characteristics)

8. 7. Mitochondria (Animal and Plant Cells) Powerhouse” – site of respiration. (Energy is released from food) singular = mitochondrion.

9. 8.Vacuole (Animal and Plant Cells) Circular sacs that store food, water or wastes

10. 9. Endoplasmic Reticulum (Animal and Plant Cells) Canal Network – passageway that functions in the movement (transport) of materials around the cell.

11. 10.Ribosomes (Animal and Plant Cells) Make proteins (protein synthesis) Ribosomes are found attached to the endoplasmic reticulum OR floating freely in the cytoplasm

12. 11.Lysosomes (Animal and Plant Cells) Digestive sacs Small oval structures that contain enzymes which digest food, destroy bacteria, and digest and recycle material from old, worn out cell parts

13. 12. Golgi complex (Golgi Body/Golgi Apparatus) (Animal and Plant Cells) Packages material to be transported out of the cell

14. A NIMAL CELLS ONLY ! 13. Centrioles Assist animal cells in cell division (reproduction)

15. P LANT CELLS ONLY !! 14. Chloroplast Make food for the plant cell (Photosynthesis ) Contain the green pigment chlorophyll which absorbs the sun’s energy.

16. 15. Cell Wall Protects and supports plant cells Composed of cellulose (non-living) The cell wall is completely PERMEABLE and cannot control what goes in and out of the plant cell

17. P LANT CELLS VS. A NIMAL C ELLS StructureGreen Plant CellAnimal Cell Cell WallYesNo ChloroplastsYesNo CentriolesNoYes VacuolesUsually LargeUsually Small

18. H OW D O M ATERIALS MOVE INTO / OUT OF CELLS ? Transport into or out of a cell can be PASSIVE TRANSPORT- does NOT require energy Examples: Diffusion, Osmosis ACTIVE TRANSPORT – REQUIRES energy

19. P ASSIVE T RANSPORT Diffusion – the movement of materials from an area of higher concentration to an area of lower concentration.

20. D IFFUSION A NIMATION Click here for animation

21. P ASSIVE T RANSPORT Osmosis – the diffusion of water across a semi- permeable membrane from an area of higher water concentration to an area of lower water concentration. Equilibrium – is reached when there is an equal concentration on both sides of the membrane. Click here for animation

22. O SMOSIS A NIMATION Click here for animation

23. A CTIVE T RANSPORT Pumping molecules against a concentration gradient (from an area of low concentration to an area of high concentration). REQUIRES ENERGY!