Cellular transport
- 1. Cellular Transport aka how to molecules move in/out of the cell?
- 2. Let’s examine the cell membrane • The membrane is selectively permeable – Allows only certain molecules to move into or out of the cell.
- 3. Molecules that can pass freely • The cell membrane is permeable to water molecules and a few other small, uncharged, molecules like oxygen (O2) and carbon dioxide (CO2).
- 4. Types of molecules that are NOT permeable to the cell membrane • Macromolecules such as proteins and RNA. • Cations such as K+, Na+, Ca+ • Anions such as Cl- • Hydrophilic molecules such as glucose
- 5. Passive Movement • Does not require energy or an action – Examples: diffusion and osmosis
- 6. Diffusion • Movement of a molecule from a high concentration to a low concentration. • Down the concentration gradient. • Think of this as rolling a ball down a hill, going from a high point to a low point
- 7. Diffusion
- 8. Osmosis • Diffusion of water, its the movement from a high concentration of solvent to a lower concentration of solvent. • Solvent is typically water
- 9. Animation: How Osmosis Works
- 10. Various osmotic conditions • Remember osmosis is all about the concentration of the solvent and the the solute. • Knowing this allows for different osmotic conditions to occur. • Think about eating a bag of salty chips… what do your lip feel like after that?? • FOR THE NEXT SECTION WE WILL DO ALL THE DRAWINGS TOGETHER
- 11. Hypertonic • Hypertonic (above normal) the cell is hypertonic to the environment,there is water movement out of cell. • hypertonic solution="more solute, less water" • The cell shrivels
- 12. Hypertonic:
- 13. Hypotonic • Hypotonic (below normal) the cell is hypotonic to the environment, there is water movement into of cell. • hypotonic solution = "less solute, more water" • The cell bursts!
- 14. Hypotonic
- 15. Isotonic • Isotonic is equilibrium and there is equal movement into and out of the cell • isotonic solution= "equal solute and water"
- 16. Isotonic
- 17. Try to figure out what is going on in the Carrot video • It’s kind of corny but • http://www.youtube.co really gets the point m/watch?v=aiUCeNs across 4bo4
- 19. So how does the cell get the other molecules what is needs to survive? • By using other mechanisms of transporting ions and small molecules across their membranes that require movement or ENERGY
- 20. Facilitated Difffusion • Uses a protein embedded in the cell membrane to “help” diffuse the molecule thru a channel • EX. (+/- )ions, sugars, and salts
- 21. Facilitated Diffusion • http://www.youtube.com/watch?v=I4123h UU8xo&feature=related
- 22. Active Transport • Movement of molecules from a low concentration to a high concentration with the use of energy. • Think of it like moving a boulder up a hill, it would require a bit of energy to get it up the hill.
- 24. Endocytosis • Engulfing of a solid or liquid • -phago (solid) • -pino (liquid)
- 25. Phagocytosis
- 26. Exocytosis • Opposite of endocytosis • The Golgi body creates a vesicle around molecules. • Moves the vesicle towards the cell membrane and gets rid of it.
- 28. Difference between each cell type Prokaryote Cells Eukaryote Cells • Do not have a defined nucleus • Contain true nuclei in which • Chromosomes are dispersed in chromosomes are compacted the cytoplasm as chromatin • Contain no membrane-bound • Contain membrane-bound organelles organelles • Have circular chromosomes • Have linear DNA called • Small chromosomes • Don't undergo meiosis but • Larger reproduce sexually by the • Reproduce sexually with the transfer of DNA fragments use of meiosis through conjugation
- 30. Examples of each type of cell