Three Sections of the Cell

2. Three Sections of the Cell • All cells take in food, rid waste, reproduce • 3 main sections • 1) Nucleus • 2) Cytoplasm • 3) Plasma Membrane

3. Cytoplasm • Jelly-like material inside of the cell • Most organelles float within • Job: Allow chemical reactions to take place

4. Plasma Membrane • Aka: Cell Membrane • Job: Boundry between inside/outside of cell & allow materials to enter/exit • Composition: Lipids & proteins = phospholipidbilayer • Semi-Permeable: only specific materials may enter and exit through pores & protein channels

5. Phospholipid Composition • 3 Parts • Polar Head • 1) Phosphate Group • 2) Glycerol • Nonpolar Tails • 3) Two chains of fatty acids • Arrangement: • Outside: Polar heads • Hydrophilic • Inside: Nonpolar Tails • Hydrophobic

6. Nucleus • Job: Controls cell activity • Inside: 1) Chromatin • long strands of DNA • DNA holds info to make proteins 2) Nucleolus: makes ribosomes

7. Endoplasmic Reticulum • Aka: ER • Rough ER: Tunnel system that transports ribosomes and proteins • Smooth ER: makes fats & breaks down toxins (no ribosomes)

8. Ribosomes • Created by nucleolus • Transported by the rough ER • Job: make proteins

9. Golgi Apparatus • Job: Package and transport proteins out of the cell • Protein Creation Process Review 1) Nucleolus makes a ribosome 2) Ribosome makes protein & travels through rough ER 3) Golgi Body packages the protein into a vesicle and exports them

10. Golgi Body in action Vesicle expels the proteins (blue dots) from the cell Golgi body is placing proteins (yellow dots) into protective vesicles

11. Do Now Activity Place the following steps of protein creation in order from start to finish…. A: Golgi body packages and exports the finished proteins in a vesicle B: Ribosomes travel along the rough ER and create proteins C: Nucleolus makes ribosomes D: Ribosomes exit the nucleus

12. Mitochondria • Powerhouse • Job: Create ATP (energy molecule) in a process called cellular respiration • Endosymbiosis theory: were once free living organisms that became parts of modern cells • Evidence: • Own DNA & ribosomes • Make proteins • Replicate

13. Lysosome • Contain digestive enzymes • Functions: 1) Kill bacteria 2) Autolysis: Destroy dying cell 3) Break down food

14. Cilia & Flagella • Used in movement • Cilia = short hair-like extensions (numerous) • Flagella = long whip-like extension (very few)

15. That one magical night, sperm cells swam with the aid of a flagellum!

17. Cell Wall • Outermost layer of plant, fungi, & bacteria cells • Job: Adds support to growing plants • Made of tough cellulose • Hard to digest • Witnessed by Robert Hooke in 1665 Cell membrane

18. Chloroplast • Job: Perform photosynthesis • Chlorophyll molecules absorb & convert sunlight into glucose (sugar) • Endosymbiosis theory: were once free living organisms that became parts of modern cells • Evidence: Own DNA, own ribosomes, make proteins, replicate CO2 + H2O + sunlight  Sugar + O2

19. Vacuole vacuole nucleus B A • Job: Stores food, water, waste, color pigments • Plant cells: Large central vacuole • Animal cells: Scattered smaller vacuoles chloroplast C

20. Animal Cells vs. Plant Cells

22. REview • Pick an organelle…any organelle. Describe its function. • Name 7 organelles that can be found within the cytoplasm. • Describe the pathway that proteins travel from creation to exportation. • List various reasons to help support the theory of endosymbiosis. • Name two organelles that plant cells have and animal cells do not. • Which organelle creates ATP energy for cells? • Which organelle converts sunlight into sugar? • Which organelle creates ribosomes? • Which organelle fuses with the cell membrane to release proteins? • Which molecule holds the information to make a protein?