Parts of Prokaryotic & Eukaryotic Cells

1. Parts of Prokaryotic & Eukaryotic Cells

2. Cell Theory • 1. All living things are made of ____________. • 2. Cells are the basic unit of __________ & __________ in an organism. • 3. All cells come from the reproduction of ____________ cells.

3. CELL MEMBRANE MODEL • Phospholipids and proteins move laterally, or side to side, for short distances. • Proteins make a pattern on the surface known as the fluid mosaic model.

4. NUCLEUS and NUCLEOLUS NUCLEUS is: • Surrounded by nuclear MEMBRANEcalled the NUCLEAR envelope. • Serves as the control CENTER OF CELL • Nuclear pores allow molecules in and out

5. NUCLEUS and NUCLEOLUS • CONTAINS CELL’S GENETIC MATERIAL ( DNA) • Contains NUCLEOLUS (Dark spot) which makes ribosomes (RNA)

6. NUCLEUS and NUCLEOLUS • Each cell has fixed number of chromosomes that carry genes • Genes control cell characteristics

7. Nuclear Envelope • Double membrane surrounding nucleus • Also called nuclear membrane • Contains nuclear pores for materials to enter & leave nucleus • Connected to the rough ER

8. CHROMATIN & CHROMOSOMES • DNA is scrunched up as CHROMOSOMES in DIVIDING CELLS • DNA is spread out as CHROMATIN in NON-DIVIDING CELLS

9. CYTOSKELETON • Made of PROTEINS called actin and tubulin. • FUNCTIONS: • Helps cell maintain its shape • Helps organelles move around

10. LYSOSOMES • Sac containing digestive enzymes • FUNCTION: Digests: food, bacteria, and worn out cell parts for cells • Plays a role in APOPTOSIS: “programmed cell death” Cell suicide for the good of the ORGANISM

11. LYSOSOMES • Cells take in food by phagocytosis • Lysosomes digest the food & get rid of wastes

12. VACUOLE • STORAGE SPACE FOR: • In plants, they store Cell Sap • Includes storage of sugars, proteins, minerals, lipids, wastes, salts, water, and enzymes • Huge in PLANT cells, small in ANIMAL cells, NOT in BACTERIAL cells.

13. VACUOLE

14. CENTRIOLES • Bundle of microtubules made of PROTEINS called tubulin. (9+3 ring) • Only seen in ANIMAL cells during cell division • Function: largely unknown, but they do assist in cell division

15. CILIA & FLAGELLA • Made of PROTEINS called microtubules– tubulin also.organized in a “9+2” arrangement • that help with moving cells, in moving fluids, or in small particles across the cell surface

16. CILIA & FLAGELLA • CILIA: shorter& more numerous; look like short “hairs” • FLAGELLA: longer & fewer; look like “tails”; typically only 1-3 per cell. • FUNCTION (BOTH): cell movement, if cell is non-motile, moves fluid over cell surface Ex.- Cilia lining your windpipe sweep mucus containing trapped debris out of your lungs.

17. CILIA & FLAGELLA

18. Cilia Moving Away Dust Particles from the Lungs

19. RIBOSOMES • Can be FREE in the cytosol or ATTACHED to the surface of Rough ER • MADE OF rRNA (ribosomal) & PROTEIN • FUNCTION: MAKE PROTEINS

20. CELL MEMBRANE or PLASMA MEMBRANE • Made mainly of PHOSPHOLIPIDS and PROTEINS • HYDROPHOBIC “tails” of phospholipids make molecules line up as a LIPID BI-LAYER with POLAR heads facing OUT and NON-POLAR tails facing IN (to inside of bi-layer)

21. Outside of cell Carbohydrate chains Proteins Cell membrane Inside of cell (cytoplasm) Protein channel Lipid bilayer CELL MEMBRANE or PLASMA MEMBRANE

22. CELL MEMBRANE or PLASMA MEMBRANE • Proteins attached to surface (inside or outside)= PERIPHERAL PROTEINS • Proteins stuck into membrane = INTEGRAL PROTEINS • (can go part way in or all the way through)

23. CELL MEMBRANE or PLASMA MEMBRANE • Membranes are selectively permeable/ semi-permeable when they allow certain molecules to pass through; but keep others out. • Cytoplasm/ cytosol is the “gel-like material + organelles” between nucleus and cell membrane

24. CELL MEMBRANE or PLASMA MEMBRANE • OTHER MOLECULES: • GLYCOPROTEINS with attached CARBOHYDRATE tails to recognize self • Contain the steroid CHOLESTEROL to make membranes more flexible

25. MITOCHONDRION (plural: MITOCHONDRIA) • Surrounded by DOUBLE membrane. Contains its own DNA. • Called the “powerhouse” of cell • Burns food (sugars, fats, etc) to release energy.

26. MITOCHONDRION (plural: MITOCHONDRIA) • Stores energy released as ATP. • Smooth outer membrane • Folded inner membrane = CRISTAE (increases surface area for more chemical reactions) Cellular respiration happens in the inner membrane.

27. MITOCHONDRION (plural: MITOCHONDRIA) • More active cells like muscle cells have MORE mitochondria • Both plants & animal cells have mitochondria

28. ENDOPLASMIC RETICULUM(ER) • Internal network of hollow membrane tubules. • Connects to nuclear envelope & cell membrane

29. ENDOPLASMIC RETICULUM(ER) • ROUGH ER • Rough ER has ribosomes on its surface, while smooth does not. • Rough ER: Attached ribosomes make PROTEINS which are modified & exported. • FUNCTION ROUGH ER: Makes membrane proteins and proteins for export out of cell

30. ENDOPLASMIC RETICULUM(ER) • Proteins are made by ribosomes on ER surface • They are then threaded into the interior of the Rough ER to be modified and transported

31. ENDOPLASMIC RETICULUM(ER) • Rough ER has RIBOSOMES on its surface, while SMOOTH does not. • Is attached to the ends of rough ER

32. ENDOPLASMIC RETICULUM(ER) • SMOOTH ER • FUNCTION SMOOTH ER: • Makes cell products that are USED In the cell • Makes membrane lipids (steroids) • Regulates calcium (muscle cells) • Destroys toxic substances (Liver)

33. GOLGI APPARATUS (BODY) • Looks like a stack of flattened sacs. • FUNCTION: Modify, sort, and package substances from ER for transport out of cell OR for storage. • Have a shipping side (cis face) & a receiving side (trans face) • Receive proteins made by ER • Transport vesicles with modified proteins pinch off the ends

34. GOLGI APPARATUS (BODY) CIS TRANS Transport vesicle

35. GOLGI APPARATUS (BODY)

36. VESICLES • Sacs made of membrane • Used to transport substances within the cell– protein from ER to Golgi to cell membrane, or to take in food (endocytosis) or get rid of wastes (exocytosis) • Disposable; pinch off of and fuse with other membranes in the cell.

37. VESICLES

38. ENDOMEMBRANE SYSTEM • Includes nuclear membrane connected to ER connected to cell membrane (transport)

39. ENDOMEMBRANE SYSTEM

40. CHLOROPLASTS • Surrounded by double membrane • Has its own DNA • Outer membrane smooth • Inner membrane sacs called THYLAKOIDS contain CHLOROPHYLL where photosynthesis happens.

41. CHLOROPLASTS • Stacks of thylakoids called GRANA. Gel like material around thylakoids called STROMA. • FOUND ONLY IN PLANT CELLS

42. CELL WALL • Found OUTSIDE the cell membrane. • Provides structure & support. • Cellulose in the cell wall makes plant cells sturdy. • Bacteria have cell walls made of peptidoglycan instead of cellulose. • Made of chitin in Fungi

43. PROKARYOTES • Bacteria are the most common prokaryotic cell. They do not have a nucleus, but do contain a single circular chromosome made of DNA, found in the NUCLEOID REGION. • Like all cells, bacteria are surrounded by a cell membrane which contains the gel-like cytosol of the cell.

44. TONOPLAST • Membrane that encloses the CENTRAL VACUOLE in a plant cell, separating it from the cytosol.

45. PEROXISOMES • Organelle containing enzymes that transfer hydrogen from various substrates to oxygen, producing and then degrading hydrogen peroxide.

46. PLASMODESMATA • An open channel in the cell wall of PLANTS through which strands of CYTOSOL connect from adjacent cells.

47. CENTROSOME • Present in cytosol of all eukaryotic cells; important during cell division; the MICROTUBULE organizing center.