CELLS

1. CELLS The basic living, structural, and functional unit of all organisms. “Captian”-Chemistry “Crunch”-Cell

2. 3.01 Identify the four principle parts of a generalized animal cell and their functions. • Nucleus – “Control Center of the Cell” • Cytosol – intracellular fluid • Organelles – “elle= small or tiny” • Cell (Plasma) Membrane • - selective permeability

3. Basic Cell

4. Basic Cell Structures

5. 3.01 Identify the four principle parts of a generalized animal cell and their functions. Nucleus The “control center” of the cell Usually the largest structure in the cell Contains genetic information Controls cellular function and structure

6. 3.01 Identify the four principle parts of a generalized animal cell and their functions. Nucleus • Nuclear Membrane • Nucleoplasm • Nucleolus • site of ribosome synthesis • Genetic Material DNA • Chromatin contains DNA in thread-like form (cell is not dividing) • Chromosomes contains DNA in short, rod-like structures (cell is reproducing)

7. Cell Nucleus

8. 3.01 Identify the four principle parts of a generalized animal cell and their functions. Cytosol Cytosol The semi-fluid component of cytoplasm or intracellular fluid 75% - 95% water May contain organelles, large carbohydrates, fat, and protein molecules

9. 3.01 Identify the four principle parts of a generalized animal cell and their functions. Cytosol Cytosol The semi-fluid component of cytoplasm or intracellular fluid 75% - 95% water May contain organelles, large carbohydrates, fat, and protein molecules

10. 3.01 Identify the four principle parts of a generalized animal cell and their functions. Organelles • Specialized structures and portions of the cell with characteristic shapes that assume specific roles: • growth • repair • maintenance • control of cellular functions

11. 3.02 Describe the structure and function of the cell membrane. • The Cell (Plasma) Membrane • Thin structure that separates the internal cellular (intracellular) components from the external environment.

12. Cell Membrane

13. 3.02 Describe the structure and function of the cell membrane. Cell Membrane Structure Phospholipid bilayer Hydrophilic phosphoric heads face outward Hydrophobic fatty acid tails face inward Carbohydrates assist in cell identification/communication Cholesterol increases strength of cell membrane

14. 3.02 Describe the structure and function of the cell membrane.(cell membrane proteins) • Integral Proteins are proteins imbedded in the phospholipid bilayer • gates or channels are transport proteins • receptor sites for hormones • enzymes • cellular identity markers • Peripheral Proteins are loosely bound to plasma membrane • function not completely understood

15. Cell Membrane Structures

16. Cell Membrane Proteins

17. 3.03 Describe a selectively permeable membrane and factors which influence permeability. Cell Membrane Function Flexible boundary Facilitates contact with other cells and environment Receptor sites - hormones, enzymes, neurotransmitters, nutrients, antibodies Selectively permeable - mediates entrance and exit of material into and out of cell.

18. 3.03 Describe a selectively permeable membrane and factors which influence permeability. Size of molecules Solubility in lipids Charge on ions Presence of carrier molecules

19. Movement Across the Cell Membrane

20. 3.04 Contrast intracellular and extracellular fluid in terms of location and composition. • Intracellular Fluid-inside the cell • Fluid found in living cells • Comprises > 66% of body’s total water • Mostly water • may also contain potassium, phosphates, magnesium, chloride, and other ions

21. 3.04 Contrast intracellular and extracellular fluid in terms of location and composition. • Extracellular/Interstitial/Intercellular/Lymph/Plasma/Cerebral Spinal • Extracellular Fluid • Fluid found in the microscopic spaces between cells • Plasma • Extracellular fluid within blood vessels

22. 3.05 Describe each of the following cellular transport processes and classify them as active or passive. • Passive Processes • No energy expenditure • Moves down a concentration gradient • High →low concentration • Active Processes • Requires energy expenditure • Moves against a concentration gradient • Low → high concentration • May utilize 40% of cells ATP supply

23. Movement Across the Cell Membrane

24. 3.05 Describe each of the following cellular transport processes and classify them as active or passive. Diffusion Facilitated Diffusion Osmosis Dialysis Filtration

25. Diffusion The movement of molecules from a higher concentration to a lower concentration. Does not require energy. Ex: perfume, electrolytes

26. Facilitated Diffusion Facilitated diffusion is the process of diffusion through the protein channels of the cell membrane. Ex: glucose

27. Facilitated Diffusion

28. Dialysis Dialysis is the diffusion of excessive particles, waste, and water through a selectively permeable membrane. Example: Kidney dialysis

29. Filtration Filtration is the process of removing particles from a solution by allowing the liquid and substances less than 10,000 Daltons to pass through a membrane. Sugar and amino acid monomers are about 100 Daltons. It is influenced by gravity and hydrostatic pressure. Example: Filtration in the glomerulus of the kidney nephron.

30. 3.05 Describe each of the following cellular transport processes and classify them as active or passive. 1. Endocytosis occurs when the molecules are too big to enter the cell by diffusion or active transport, a vesicle is formed from the cell membrane. Example: Phagocytosis or cell eating.

31. 3.05 Describe each of the following cellular transport processes and classify them as active or passive. 2. Exocytosis Any remaining particles from phagocytosis may be expelled from the cell when the vesicle joins with the cell membrane and the contents are removed from the cell.

32. 3.05 Describe each of the following cellular transport processes and classify them as active or passive. • Active Transport • Uses energy • Ions move against a concentration gradient • Na+/K+ pump • Estimated 40% ATP use in the body • Cytosis (Bulk Transport) • Endocytosis • Phagocytosis - cell eating • Pinocytosis - cell drinking • Receptor mediated endocytosis • Exocytosis

33. Na+/K+ Pump

34. 3.06 Review the osmotic effects that occur when a cell is placed in an isotonic, hypotonic, or hypertonic solution. Isotonic Solutions Hypotonic Solutions Hypertonic Solutions

35. Osmosis

36. Tonic Solutions

37. 3.07 Describe the function of the following structures within the cell. Inside the Nucleus • Nucleolus • Site of ribosome production (rRNA). • DNA • Double stranded helix of genetic material inside the nucleus. • RNA • Single stranded genetic material produced in the nucleus and exits through nuclear pores. • (mRNA, tRNA, rRNA)

38. 3.07 Describe the function of the following structures within the cell. Inside the Nucleus • Chromosome • tightly packed DNA prior to cell division. • Chromatin • (thread-like) loosely packed DNA. • Gene • a segment of DNA that codes for a protein.

39. Cell Nucleus

40. 3.07 Describe the function of the following structures within the cell. Organelles • Specialized structures and portions of the cell with characteristic shapes that assume specific roles: • growth • repair • maintenance • control of cellular functions

41. Organelles and Structures • Ribosomes • Endoplasmic Reticulum • Golgi Complex • Mitochondria • Lysosomes • Peroxisomes • Microfilaments • Microtubules • Centrioles • Centrosomes • Flagella • Cilia • Microvilli • Vacuoles

42. Ribosomes Appear as small, round, granular structures within the cell Sites of protein synthesis by assembling the amino acids in the correct order. Made up of special type of RNA called ribosomal RNA (rRNA)

43. Endoplasmic Reticulum • Double membranous channels which are continuous with the nuclear membrane • Granular (Rough) Endoplasmic Reticulum • studded with ribosomes • site of protein synthesis • Agranular (Smooth) Endoplasmic Reticulum • free of ribosomes • site of lipid synthesis

44. Functions of Endoplasmic Reticulum Mechanical support and distribution of cytoplasm Surface area for chemical reactions Intracellular transport system Storage of synthesized molecules Protein (RER) synthesis Lipid (SER) synthesis Detoxification of certain molecules Release of calcium ions in muscles

45. Golgi complex (apparatus) Flattened membranous sacs (4 - 8) stacked upon one another Processes, packages, sorts, and delivers proteins to various parts of the cell Secretion of lipid molecules for transport around the cell Form lysosomes from the trans face

46. Vesicles (Vacuoles) • Fluid and product filled organelles enclosed by a lipid bilayer membrane • Varied storage functions are for metabolism (digested cellular food or water), transport, enzymes, and chemical RXN.

47. Lysosomes • Nicknamed “suicide packets” • Small membrane enclosed spheres of digestive enzymes • Intracellular digestion • Autophagy is the process by which old worn out organelles are digested • Autolysis is the process by which lysosomes digest themselves

48. Peroxisomes Similar to lysosomes but much smaller Usually found in the liver and kidney Must have metabolic oxygen present to function properly Role in detoxifying molecules (alcohol) Break down fatty acids through beta-oxidation.

49. Mitochondria • Powerhouse of the cell • Small, spherical or rod-shaped structures • Sites of cellular respiration • conversion of glucose and lipids to ATP • aerobic energy metabolism • Krebs cycle/TCA cycle/citric acid cycle • Mitochondrial Electron Transport

50. Mitochondria