1. Cells Chapter 7

2. The size range of cells

3. Why are cells so small? Small cells have a high surface area to volume ratio which allows more stuff to move in and out of the cell

4. CELL THEORY Living organisms are composed of one or more cells Cells are the smallest unit of life Cells come from other cells

5. ALL CELLS HAVE Plasma membrane –Outer layer Cytoplasm –Watery stuff inside DNA –Genetic material Ribosomes –Make proteins

6. TWO BASIC CELL TYPES

7. Prokaryotic Cells DNA in nucleoid region No membrane-bound organelles No nucleus Small Bacteria

8. Plasma Membrane aka: The Gate-keeper

9. Overview of an Animal Cell

10. Overview of a Plant Cell

11. Nucleus & Nuclear Envelope

12. Ribosomes

13. Endoplasmic Reticulum (ER)

14. Golgi Apparatus

15. Lysosomes Sac of hydrolytic enzymes Digests macromolecules Breaks down dead organelles pH ~ 5

16. Formation & Function of Lysosomes

19. The Endomembrane System

20. Mitochondria Site of Cellular Respiration, Makes ATP

21. Chloroplast Site of Photosynthesis Converts energy from sunlight to chemical energy stored in sugar

22. Central Vacuole: Plant Cells Stores Water Waste Nutrients Makes plant cell turgid

23. Peroxisomes Produce and break down H 2 O 2

24. Cytoskeleton Network of fibers throughout cytoplasm Gives cell shape Holds organelles in place Involved in movement & changing shape

26. Motor Molecules & Cytoskeleton Changing shape Cilia movement Flagella movement Organelles move along microtubule or microfilament Ex: Vesicle transport

27. Centrioles Centriole: 9x3 ring of microtubules Involved in cell division

28. Structure of Eukaryotic Cilia/ Flagella 9x2 + 2 ring of microtubules Covered in plasma membrane Basal Body Anchors cilia/ flagella to cell 9x3 ring of microtubules

29. Wave Back and forth

30. Dynein “walking” moves Cilia and Flagella Powered by ATP Dynein arms grip adjacent microtubule Grip, pull, release – repeat Results in bending of microtubules

31. Microfilaments (actin filaments) Pulling force –Muscle contraction –Cytoplasmic streaming –Pseudopodia Part of Extracellular Matrix –Support cell membrane –Inside of cell membrane

32. Extracellular Matrix

33. Plant Cell Walls Protects cell Gives cell shape Prevents excessive uptake of H20 Primary, secondary walls Plasmodesmata –Cell to cell communication –Cytoplasm continuous from one cell to other Middle lamella cements cells together

34. Cell Junctions in Animal Cells Fuses membranes Strong sheets Pass ions and small molecules