1. Types of Cells and Cellular Organization

2. Two Basic Cell Types Prokaryotes: “Pro”= before; “karyon”= nucleus “Pro”= before; “karyon”= nucleus Cells that do not contain any membrane-bound organelles Cells that do not contain any membrane-bound organelles Most unicellular (one cell) organisms; bacteria Most unicellular (one cell) organisms; bacteria 0.5 -5 μm diameter; smaller ribosomes 0.5 -5 μm diameter; smaller ribosomes

3. Prokaryote Structures All prokaryotes have: Cell wall, plasma membrane, cytoplasm, ribosomes, and nucleoid (circular DNA) Cell wall, plasma membrane, cytoplasm, ribosomes, and nucleoid (circular DNA) Additional structures: Flagellum  tail for locomotion Flagellum  tail for locomotion Capsule  protective layer;prevents dehydration Capsule  protective layer;prevents dehydration Mesosome  aid cell wall formation Mesosome  aid cell wall formation Plasmid  small rings of extra DNA Plasmid  small rings of extra DNA Pili  sticky points that help cell stick to surfaces; pass plasmids to other prokaryotes Pili  sticky points that help cell stick to surfaces; pass plasmids to other prokaryotes

4. Two Basic Cell Types Eukaryotes : Cells that do contain membrane-bound organelles Cells that do contain membrane-bound organelles Most multicellular (many cells) organisms; plants, animals, fungi, etc. Most multicellular (many cells) organisms; plants, animals, fungi, etc. Some unicellular organism too; protoctists Some unicellular organism too; protoctists 10-100 μm; larger ribosomes 10-100 μm; larger ribosomes

5. Prokaryote Vs. Eukaryote ProkaryoteEukaryote No membrane-bound organelles Membrane-bound organelles No nucleusNucleus Small (0.5- 5 μm)Large (10-100μm) Small RibosomesLarge Ribosomes Small, normally circular DNALarge, linear DNA

6. Practice 1) A toxin deadly to humans is being tested in a lab. The toxin binds to ribosomes and prevents them from making proteins. The toxin is introduced to a colony of E. coli, a common bacteria used in labs. What kind of result could you expect a day after the toxin is added? Why? 2) Will protective masks with 0.007mm filters help stop the spread of an airborne toxic bacterium? Why? 2) Will protective masks with 0.007mm filters help stop the spread of an airborne toxic bacterium? Why? The bacteria will grow as normal. The ribosomes of bacteria are too small to be affected No. Bacteria are too small (0.5- 5 μm)

7. Organizing an Organism C ell compartmentalize to divide labor C ell compartmentalize to divide labor How are organisms the same? How are organisms the same? Organs designed for specific jobs Organs designed for specific jobs Cells  Tissue  Organ  System  Organism Cells  Tissue  Organ  System  Organism Tissue  cells of same type or mixed type Tissue  cells of same type or mixed type Histology  study of tissues Histology  study of tissues Organ  formed from tissues to do a specific job (digest, move blood, see, etc.) Organ  formed from tissues to do a specific job (digest, move blood, see, etc.) System  organs working together for a whole body function (respiration, excretion, etc.) System  organs working together for a whole body function (respiration, excretion, etc.)

8. Observing Tissues Plan diagram  mapping out tissues in a section of an organism Plan diagram  mapping out tissues in a section of an organism Focus is tissues not cells Focus is tissues not cells Plant tissue: Plant tissue: Upper epidermis  water proof outer covering; covered with cuticle Upper epidermis  water proof outer covering; covered with cuticle Palisade mesophyll  photosynthetic cells Palisade mesophyll  photosynthetic cells Spongy mesophyll  space for CO 2 circulation Spongy mesophyll  space for CO 2 circulation Phloem  transport solutes Phloem  transport solutes Xylem  transport water and salts Xylem  transport water and salts Lower epidermis  stomata for gas exchange Lower epidermis  stomata for gas exchange

9. Observing Tissues How would you plan out a cross section of plant stem? How would you plan out a cross section of plant stem? Pith  food storage cells Pith  food storage cells Cortex  main growth cells in stem; various other jobs Cortex  main growth cells in stem; various other jobs Cambium  produce specialized cells Cambium  produce specialized cells Why no mesophyll? Why no mesophyll? No photosynthesis in the stem No photosynthesis in the stem

10. Animal Tissue Layers 3 Major Layers  3 Major Layers  Ectoderm  outer layer; skin, nerves, pigments Ectoderm  outer layer; skin, nerves, pigments Mesoderm  middle layer; muscles, bones, connective tissue, organs Mesoderm  middle layer; muscles, bones, connective tissue, organs Endoderm  inner layer; digestive tract, respiratory tract, excretion Endoderm  inner layer; digestive tract, respiratory tract, excretion

11. Homework Read pages 21- 28 Read pages 21- 28 Answer questions 1.5 and 1.6 Answer questions 1.5 and 1.6 Finish Cell Analogy worksheet Finish Cell Analogy worksheet