1. Cell Terms (Prefixes):
Cyto – having to do with cells
Hypo – below or under
Hyper – above or beyond
Philic – loving
Phobic – fearing
Exo – exit or out
Photo – light
Endo – into
Phag – To eat
Pino – To drink
Glyco – having to do with sugar

2. Laminin Laminin is a cell binding protein.
laminin is a protein found in the "extracellular matrix", the sheets of protein that form the substrate of all internal organs also called the "basement membrane". It has four arms that can bind to four other molecules. The three shorter arms are particularly good at binding to other laminin molecules, which is what makes it so great at forming sheets. The long arm is capable of binding to cells, which helps anchor the actual organs to the membrane.
They are a family of glycoproteins that are an integral part of the structural scaffolding in almost every animal tissue. Laminins are secreted and incorporated into cell-associated extracellular matrices. 2

3. Diversity of cells – over 200 different kinds in the human body alone!

4. You can be 100% sure that this will be on the test!
The 3 postulates of the cell theory:
All living things are made up of 1 or more cells
Cells are the basic unit of life
All cells come from pre-existing cells

5. Cells: A quick review
Cells were discovered in the 17th century (late 1660’s) by Robert Hooke, who was observing cork cells (right)

6. Cells: A quick review Two different types of cells: Prokaryotic
lacks a nucleus
Lacks any membrane-bound organelles
Eukaryotic
Contain a nucleus and membrane bound organelles. Two prominent members are plant cells & animal cells

7. Prokaryotic Cells Smallest and simplest cells
A prokaryote is any single celled organism that lacks a nucleus and other membrane bound organelles.
Bacterium are the major example of prokaryotic cells

8. Prokaryotic Cells:
1. Have single-stranded, circular DNA
2. NO internal compartments (no membrane bound organelles.)
3. Have a cell wall (like plants and fungi) that serves to support and protect the cell.
4. Cell wall made of peptidoglycan instead of cellulose
5. Many have a flagellum

9. Eukaryotic Cells Much more complex than prokaryotic cells.
Contain a nucleus and other membrane-bound organelles
Two major kinds of eukaryotic cells are:

10. Plant Cells Have a cell wall composed of cellulose
Have a large central vacuole
Contain chloroplasts

11. 1. The Cell Wall -Made of a polysaccharide called cellulose.
-Utilized for structural support; when the vacuole is full, turgor pressure is created and the plant can maintain its rigidity because of the sturdiness of the cell wall.

12. 2. Vacuole
Vacuoles can store metabolic wastes, some of which are economically important to us. (caffeine, nicotine, etc.)
Loss of water = loss of turgor pressure. What will happen then?

13. 3. Chloroplasts Site of photosynthesis and energy production in plants
Utilize light energy, CO2, and H2O to make sugar.
Equation:
6 CO2 + 6 H2O =
C6H12O O2
What are these compounds?

14. Animal Cells Lack a cell wall, have a cell membrane instead.
Don’t have cellulose or chloroplasts
Vacuole is much less prominent

15. CELL ORGANELLES
Cells contain smaller specialized structures called organelles.

16. Plasma Membrane
Plasma membrane is a phospholipid bilayer

17. Plasma Membrane
Made of a special kind of lipid called a “phospholipid”
Has a hydrophilic head & two hydrophobic fatty acid tails
In a double-layered configuration commonly called a “bi-layer”

19. Plasma Membrane Plasma membrane is a phospholipid bilayer
Fluid-mosaic model containing:
Membrane proteins (channel proteins, trans-membrane proteins, receptor proteins etc.)
Glycoproteins (marker proteins)
Cholesterol

20. Membrane Proteins
Various proteins are located in the lipid bilayer of the cell membrane
Glycoproteins (marker proteins) have attached carbohydrate groups and can advertise the cell type. ( self/other) Also -hepatic, renal, cardiac, etc)

21. Membrane Proteins
Receptor Proteins recognize extra-cellular substances
Transport Proteins (also called channel proteins) assist in moving substances in or out of the cell; crossing cell membrane (ex.-sodium/potassium pump)

22. Membrane Protein Receptors
“Seeing eye dog” for the cell
Tells cell what molecules are in the extra-cellular environment
Identifies cells to each other (AIDS virus to the right)
NOTES
Since the AIDS virus mimics the protein coating (and thus membrane receptors) of Healthy human Leukocytes, it is impossible at this time to keep AIDS from spreading inside the host human once it has been contracted. It is the gift that keeps on giving!

23. 23

24. Movement in Vesicles Movement into the cell is termed ENDOcytosis
Endo = “into”
Cyto = “cell”

25. Endocytosis
Phagocytosis is one kind of endocytosis; in which a cell engulfs a foreign body (Immune response)
Cells take in cholesterol through endocytosis
Notes
LDL = low density lipoproteins (carry cholesterol to the cells.)
HDL = high density lipoproteins (carry cholesterol away from the cells.)

26. Movement in Vesicles Movement out of the cell is termed EXOcytosis
Exo = “away from” or “out of”
Cyto = “cell”

27. Movement of a substance from an area of higher concentration to an area of lower concentration is called diffusion.
Will continue, if allowed to, until equilibrium is reached
Diffusion

28. Equilibrium
Equilibrium is a condition in which the concentration of a substance is evenly distributed throughout space.
Notes
Recount the story of trying to impress the young lady at the Church of Christ Student Center, the backyard swing, while playing E.C.U.
Demonstrate with students standing on an imaginary scale, like the one shown.

29. Osmosis is the diffusion of water across a membrane.
Water moves through special channels in the membrane known as “aquaporins”.

30. Osmotic Pressure
Osmotic Pressure is the force exerted on the membrane as water moves across it in an attempt to reach equilibrium. The farther out of equilibrium, the greater the osmotic pressure, and the more water will move across the membrane.

31. Concentration Gradient
A difference in the concentration of a substance across a membrane is called a concentration gradient.
If the membrane is permeable to the substance, the concentration gradient will eventually reach equilibrium.

32. Passive Transport:
Movement across a cell membrane that does NOT require energy from the cell is called passive transport.
In many animal cells, water and most fat soluble (non-polar) compounds are able to passively cross the cell membrane.

33. Selective Permeability
The cell membrane is selectively permeable to extra-cellular substances
The cell membrane is “picky” about who it lets through the membrane! (NO polar ions!)
What is an “extra-cellular substance”? (things outside the cell)

34. Crossing the Cell Membrane
Ions, because of their electrical charge, have to go to the gate!
The gate is called an “ion channel”.
Sodium (Na+)
Potassium (K+)
Calcium (Ca ++)
Chloride (Cl-)

35. Ion channels in a cell membrane

36. The 2 kinds of “gates” on ion channels
Chemical gates
Activated by a certain chemical (Acetylcholine for example)
Voltage gates
Activated by a change in polarity

37. -Notes
Nice-to-know information only…not test material

38. -Notes
Nice-to-know information only…not test material.

39. Water movement across the cell membrane
Speed of water movement across the membrane depends on the concentraion gradient. The greater the difference in the amount of solutes (particles) in the solution, the more water will flow across the membrane.

40. Water movement across the cell membrane
Three possible conditions resulting from the osmotic pressure and concentration gradient.
Hypertonic
Hypotonic
Isotonic
Notes
Osmotic pressure is which direction water will move, via osmosis, to try and reach a state of equilibrium.
(The farther out of equilibrium, the greater the “osmotic pressure”, and the more water will move across the membrane)

41. Hypotonic (“Hypo” = less than)

42. Isotonic (“Iso” = same)

43. Hypertonic (“Hyper” = more than)

44. Tonicity
When a cell swells until it ruptures, we call it “cytolysis” or “plasmolysis”.
When a cell shrivels up from loss of water, we call it “crenation.”

45. Tonicity in plant cells

46. So, tell me why…
Answer:
Those “poles” are the cytoskeleton framework underneath; they protrude out much like a collapsed circus tent!
Why does a crenated erythrocyte (shriveled up red blood cell) have those little ridges and poles jutting out everywhere?
Anyone have a guess?
The ridges and poles come from the cytoskeleton underneath. (next slide)

47. Ion transport
An ion’s charge affects its diffusion rate across the cell membrane.
Typically, the inside of a cell membrane is more negatively charged than the outside. (Remember, like charges repel, but opposites attract.)

48. Ion Transport
A negatively charged ion INSIDE the cell will diffuse out easier. (Cl-)
A positively charged ion OUTSIDE the cell will diffuse into the cell easier (drawn in electromagnetically)
Na+ K+
Ca 2+ + + + + _ _ + _ + _
Inside of cell membrane is NEGATIVELY charged! _ _ + _ _ + _ _ + _ + + +
Outside of membrane is POSITIVELY charged!

49. Facilitated Diffusion
Cells have “carrier proteins” used to transport specific substances across the cell membrane.
Used for amino acids and glucose
Is a PASSIVE type of transport (weird, huh?)

50. Active Transport
Passive Transport can only move substances DOWN the concentration gradient
To transport substances AGAINST the concentration gradients requires ACTIVE transport!

51. Active Transport Requires ENERGY from the cell, supplied by ATP
Trans-membrane carrier proteins are utilized; often called “pumps”
“Trans-membrane” means they span the entire bilayer membrane.

53. Sodium-Potassium “pump”
Sodium-Potassium pump is powered by the cells ATP
3 Sodium ions out of the cell and 2 Potassium ions into the cell with each cycle

54. Importance of Sodium-Potassium pump
1. Keeps excess sodium ions from accumulating inside the cell (remember, sodium ions are continually diffusing into the cell through ion channels embedded in the cell membrane).
Hemolysis Notes
The excess accumulation of sodium inside the cell, if the sodium-potassium pump were inactive, would artificially raise the concentration gradient of sodium inside the cell. To compensate, water would diffuse into the cell until hemolysis occurred!
Thus, if you had no sodium potassium pump, all your cells would burst within minutes! So which “evolved” first? The cell membrane or the pump? They are irreducibly complex!

55. Mitochondria “Powerhouse” of the cell
Contains some DNA (circ.) and ribosomes
Produces the cell’s ATP (& thus energy)
Cells that have high energy requirements usually have many mitochondria

56. Lysosome Lysosome acts like the “stomach” of the cell
Contains enzymes that break down proteins, lipids, carbs, & nucleic acids
Absence of working lysosomes (& the enzymes it contains) can lead to cellular waste storage disorders such as Tay-Sachs disease

57. Ribosomes Are the workbenches that proteins are made on.
Composed of RNA and proteins
“Free” ribosomes make intra-cellular proteins
Ribosomes attached to the E.R. make proteins for exocytic purposes

58. Endoplasmic Reticulum

59. Rough Endoplasmic Reticulum
Called “rough” because it has attached ribosomes, looks “rough” through a microscope
Makes proteins for transport out of the cell (exocytosis)
Proteins packaged and transported out in “vesicles”; often go to the Golgi for further modification.

60. Smooth Endoplasmic Reticulum (E.R.)
Smooth E.R. lacks ribosomes, and thus makes NO proteins
Involved in lipid synthesis (such as steroid hormones), detoxification, and carbohydrate metabolism

61. Golgi Apparatus
Adds sugar “name tags” to proteins & lipids to form “glycoproteins” and “glycolipids”.
Products are then sent in vesicles to other parts of the cell; their destination is determined by the “name tag” that the Golgi has given them.
(Ex- Mannose-6-phosphate is given to mark a protein as a lysosomal enzyme)
Brennon

62. “processing and packaging center of the cell.”

63. Cilia & Flagella Projections from the cell:
Cilia are designed to move things over or around the cell
Flagella are designed to move the cell itself through the environment (Ex: bacteria)

64. Cilia in the human trachea and respiratory system:
(The hairs undulate to sweep debris up & out of the respiratory passages)

65. Ciliary Action (clears out the junk)

66. An example of bacterial flagella’s
Salmonella w/ many flagella
Flagella:
Bacterial flagella move the cell by corkscrewing through the fluid medium in which they live.
Eukaryotic flagella are more complex structures composed of microtubules that whip back and forth for locomotion
E.Coli picture and model showing three easily distinguishable flagella

67. Centrioles
Centrioles are composed of 9 groups of 3 microtubules. ( arrangement)
Arrange and organize spindle fibers during cell division.

70. Packaging and Distribution of proteins
Vesicles containing newly made proteins move through cytoplasm from Rough E.R. to Golgi Apparatus
Golgi Apparatus modifies proteins (checks folding, or refolds)
Golgi then repacks proteins in new vesicles and sends them on
Either out of the cell, or to the lysosome (if tagged w/ Manose-6-phosphate)

71. Nucleus Center of the cell, membrane bound
Has holes called “nuclear pores” which serve as transport routes into and out of nucleus
Contains the DNA (hereditary information), which is coiled around proteins called “Histones”
Normal humans have 46 chromosomes

72. Nucleus
Nuclear pores have holes around them called “Nuclear Pore Complexes” (NPC)
To move through the NPC, molecules have to have the right “name tag” (5-methyl guanosine)

73. Cytoskeleton

74. Cytoskeleton Gives the cell structural support
Present in all cells (Eukaryotic & Prokaryotic)
Is a dynamic (as opposed to static) structure that enables cell motility and cell shape.

75. Study these for the test:
Cell Theory
3 postulates
Cell Prefixes & Terms
From 11 term list; cyto, glyco, trans, pino, phag, etc.
Cell Organelles
Nucleus, Nucleolus, Golgi, Smooth ER, Rough ER, Chloroplasts, Cell Wall, Vacuole, Lysosome, Ribosomes, Centrioles, Cytoskeleton, etc.
Cell Environment
Diffusion, Osmosis, Osmotic Pressure, Active Transport, Passive Transport, Ion Transport, Tonicity (Hypotonic, Hypertonic, & Isotonic) etc.