1. 1. “VOLUME” Cytosol and Cytoplasm
cytosol: viscous liquid in cell
analogy: JELL-O
cytoplasm: viscous liquid + cell organelles
analogy: JELL-O w/ fruit
Eukaryotic cells have compartmentalized organelles, meaning the organelles are separated from the rest of the cell by membranes. Of course, the cell itself is enclosed by a plasma membrane. The space between the organelles and the plasma membrane is filled with some gel-like, gooey stuff called cytosol.
We can differentiate the cytosol from cytoplasm like this:
* Cytosol is found between the organelles and the cell (plasma) membrane, but does not include the organelles and plasma membrane in its definition. Thus, only eukaryotic cells have cytosol in this sense because only eukaryotic cells have compartmentalized organelles. Cytosol is comprised of a lot of water, dissolved ions, large water soluble molecules, smaller molecules, and proteins. Metabolic processes and cell communication occur within the cytosol. Proteins are synthesized in the cytosol (translation). Metabolic (anabolism and catabolism) processes occur within the cytosol.
* Cytoplasm refers to everything that is found within the plasma membrane. It includes the cytosol, endomembrane system, and cell organelles. Both eukaryotic cells and prokaryotic cells have cytoplasm. Cytoplasm is made of water up to 80% nucleic acids, enzymes, lipids, non-organic ions, amino acids, carbohydrates, and lightweight molecular compounds.

2. 2. Flagella and Cilia
flagella: long extension of cell surface, ex. tail of a sperm cell
analogy: people mover
cilia: short extensions of cell surface, move cell, move substances across the cell, ex. surface of paramecium
analogy: legs

3. 4. Cytoskeleton
cytoskeleton: “skeleton” of the cell, allows for movement within cell, made of microtubules and microfilaments
analogy: human skeleton
Microtubules (25 nm diameter) - moves stuff around the cell, make up cilia and flagella, assist during cell division
Actin filaments (8 nm) – involved in muscle contraction, assist during cell division
Intermediate filaments (10 nm) – provide structure and strength in the cell

4. 5. Cell Membrane
cell membrane: phospholipid and protein “skin” around cytoplasm, selectively permeable (allows certain materials into/out of cell
analogy: security guard
Draw and label the diagram on next slide.
All cell membranes are dynamic, fluid structures. Most of their lipids and proteins are able to move about rapidly in the plane of the membrane. This has lead to the term “fluid mosaic model" as a description of the structure of cell membranes.
Many membrane proteins are held in the bilayer by “hydrophobic" interactions with lipid molecules. Membrane proteins may be associated with the lipid bilayer in one of three ways:
1) Some proteins are known to extend across the bilayer (integral membrane proteins)
2) Some to be held by non-covalent interactions with other membrane proteins.
3) Recently, it has been shown that some membrane proteins have one or more covalently attached fatty acid chains that help anchor the protein in one monolayer or the other (these may or may not be integral membrane proteins).

5. Phospholipids
Integral protein
Peripheral protein
Fatty acid “tails” (lipids)
Phosphate Group

6. 6. Nucleus
nucleus: membrane-bound structure, contains genetic info, nuclear pores allow RNA and ribosomal subunits to leave nucleus
analogy: brain

7. 7. Nucleolus
nucleolus: dark spot inside nucleus, where ribosomal subunits are made (leave through nuclear pores)
analogy: Lego factory

8. 8. DNA DNA: found in nucleus (eukaryotes) and in cytosol (prokaryotes)
chromatin: unwound, “working DNA” (replication, repair, transcription)
chromosomes: “copied DNA” (condense for cell division)
analogy: information in an encyclopedia

9. 9. Ribosomes
ribosomes: most numerous organelle, protein synthesis, free-floating (cytosol), attached to rough ER
analogy: Garage Band

10. 10/11/12. Rough and Smooth Endoplasmic Reticulum and Vesicle
rough ER: stores and transports proteins, sends proteins to Golgi
analogy: highway
smooth ER: detoxifies (lots in liver cells), phospholipid and steroid production, transport
analogy: filter
vesicle: membrane-bound, storage (ex. proteins from ribosome)
analogy: Rubbermaid container
smooth ER: (lacks ribosomes): steroid and phospholipid production, little smooth ER except in hepatocytes (liver cells), detoxification

11. 13. Golgi Apparatus
Golgi: receives raw material from ER, modifies, processes, and sorts material into vesicles to be sent to cytosol or out of cell
analogy: post office

12. 14. Lysosomes
lysosomes: digest worn out cell parts (enzymes), digest food absorbed by the cell, mainly in animal cells (100s per cell)
analogy: garbage disposal

13. 15. Mitochondria
mitochondria: makes the cell’s energy (ATP), folded inner membrane = increased surface area, has its own DNA
analogy: power plant

14. 16. Cell Wall
cell wall: strong, outer covering of plant cells, contains cellulose, support, prevents dehydration
analogy: castle wall

15. 17. Vacuoles (animal cells) and Central Vacuole (plant cells)
vacuoles: animal cells, small and numerous, accumulate toxic wastes, storage
analogy: sponges (clean up and remove water)
central vacuole: up to 90% of plant cell’s volume, keeps cell pressurized (“turgidity”)
analogy: swimming pool

16. 18. Chloroplast
chloroplast: plant cells, type of plastid filled with chlorophyll, turns solar energy into chemical energy (glucose)
analogy: oven

17. 19. Centrosomes
centrioles: animal cells, in pairs, organize chromosomes during cell division
microtubule-organizing center (MTOC): plant cells, same function as centrioles