1. TAKS Objective 2 TEKS 4B Presented by: Alexander Fedorov Composite Science Teacher www.myscienceparty.org Applicable Text: Prentice Hall Biology: Chapter 19

2. All life is composed of cells. Three basic types of cells you will need to know (plus viruses) Prokaryotes (Bacteria) Plants Cells Animal Cells Viruses (not considered living organisms)

3. Prokaryotes (Bacteria) do not have a membrane bound nucleus!

6. Not a Living organism

7. Homeostatis This is a term to describe “constant internal enviornment.” All living things want to maintain a constant internal enviornment; for example, your normal temperature does not fluctuate with the outside temperature. We always maintain a temperature around 98.6 This is a term to describe “constant internal enviornment.” All living things want to maintain a constant internal enviornment; for example, your normal temperature does not fluctuate with the outside temperature. We always maintain a temperature around 98.6 o C.

8. Occurs at the cell membrane

9. Passive Transport: requires no energy. Passive Transport: requires no energy. Examples of passive transport:Examples of passive transport: 1. diffusion: movement of molecules from high concentration to low concentration. 2. osmosis: movement of water across a permeable membrane from an area of high concentration to low concentration.

10. BUT: There are some molecules that are too large to pass through the phospholipid bilayer. BUT: There are some molecules that are too large to pass through the phospholipid bilayer. Therefore, some molecules must undergo passive transport by means of transport proteins. Therefore, some molecules must undergo passive transport by means of transport proteins. This is called:FACILITATED DIFFUSION This is called:FACILITATED DIFFUSION

11. There are two types of transport proteins: There are two types of transport proteins: 1. channel proteins 2. carrier proteins

12. Channel proteins are tubelike and provide openings through which particles can diffuse. Channel proteins are tubelike and provide openings through which particles can diffuse.

13. Carrier proteins have a specific shape that fits a specific molecule. Carrier proteins have a specific shape that fits a specific molecule. When the proper molecule combines with the protein, it changes shape and moves the molecule across the membrane. When the proper molecule combines with the protein, it changes shape and moves the molecule across the membrane.

14. Facilitated diffusion is passive and requires no energy. Facilitated diffusion is passive and requires no energy.

15. Can a cell ever move particles from a region of lesser concentration to a region of greater concentration? Can a cell ever move particles from a region of lesser concentration to a region of greater concentration? Yes, but energy must counteract the tendency of the molecules to move in the opposite direction. Yes, but energy must counteract the tendency of the molecules to move in the opposite direction.

16. The transport of materials against a concentration gradient requires energy (ATP) and is called ACTIVE TRANSPORT. The transport of materials against a concentration gradient requires energy (ATP) and is called ACTIVE TRANSPORT.

17. First a transport protein binds with the substance to be transported. First a transport protein binds with the substance to be transported. Energy from the cell is used to change the shape of the proteins so that the particle is released on the other side of the membrane. Energy from the cell is used to change the shape of the proteins so that the particle is released on the other side of the membrane. Once the particle is released, the protein regains its’ original shape. Once the particle is released, the protein regains its’ original shape.

18. Some cells can take in large molecules, groups of molecules, or even whole cells through ENDOCYTOSIS. Some cells can take in large molecules, groups of molecules, or even whole cells through ENDOCYTOSIS.

19. The reverse process of endocytosis is EXOCYTOSIS. Cells use this to expel wastes, and secrete cellular products. The reverse process of endocytosis is EXOCYTOSIS. Cells use this to expel wastes, and secrete cellular products.

21. PASSIVE TRANSPORT: PASSIVE TRANSPORT: 1. no energy 1. no energy 2. movement of molecules from high concentration to low concentration. 2. movement of molecules from high concentration to low concentration. 3. Examples: 3. Examples: diffusion, osmosis, facilitated diffusion diffusion, osmosis, facilitated diffusion ACTIVE TRANSPORT: ACTIVE TRANSPORT: 1. requires energy 1. requires energy 2. movement of molecules from low concentration to high concentration. 2. movement of molecules from low concentration to high concentration. 3. use of transport proteins 3. use of transport proteins 4.exocytosis and endocytosis are active transport for large molecules, wastes, and cellular products. 4.exocytosis and endocytosis are active transport for large molecules, wastes, and cellular products.

23. The movement of molecules from an area of high concentration to an area of low concentration is called diffusion. The movement of molecules from an area of high concentration to an area of low concentration is called diffusion. Ex. Perfume diffusing through the airEx. Perfume diffusing through the air Food coloring diffusing in waterFood coloring diffusing in water

24. II.Permeability II.Permeability A material is permeable if it allows molecules to pass through. A material is permeable if it allows molecules to pass through. The cell membrane (plasma The cell membrane (plasma membrane) is permeable. membrane) is permeable. Hey, sponges are permeable too!!

25. III. Osmosis III. Osmosis Osmosis is the diffusion of water molecules across a permeable membrane. Osmosis is the diffusion of water molecules across a permeable membrane. In osmosis, like diffusion, water molecules move from an area of high concentration to low. In osmosis, like diffusion, water molecules move from an area of high concentration to low.

26. Hypotonic solutions- Hypotonic solutions- Solutions which contain a lower concentration of dissolved substances than a solution to which it is being compared. In a hypotonic solution the cell swells or possibly explodes Red blood cell placed in distilled water

27. Hypertonic Solution Hypertonic Solution Solutions which contain a higher concentration of dissolved substances that the solution to which it is being comparedSolutions which contain a higher concentration of dissolved substances that the solution to which it is being compared In hypertonic solutions the cell shrinksIn hypertonic solutions the cell shrinks Red blood cell placed in salt water solution

28. Isotonic solutions Isotonic solutions When the solution in side the membrane is the same concentration as the solution outside the membrane. An isotonic solution is at equilibrium In an isotonic solution there is no change in the cell Red blood cell in an isotonic solution

29. ABC D E 1.Which is the most hypertonic solution? 2.Which is the most hypotonic solution? 3.Which solution is isotonic?

30. Mitochondria: cell energy is produced Chloroplasts: create sugar by sunlight (plant cells) Lysosomes: the stomach of a cell, digests food. Ribosomes: creates protien Nucleus: stores genetic information (DNA) Cytoplasm: the cells circulation (fluid) Endoplasmic Reticulum: modifies protiens Golgi Body: packages protiens for export

31. Where they occur: Kreb Cycle: Mitochondria Calvin Cycle: Chloroplasts Glycolysis: cytoplasm Fermentation: cytoplasm Protein Synthesis: ribosomes Transcription: Nucleus Translation: ribosomes