18/27/2012Chapter 2: The CellLots of difference cellsPlasmalemma- separates cell contents (cytoplasm) from extracellular fluid- lipid bilayer [phospholipids, proteins, CHO (carbohydrate), steroids]- Isolates, protects cell- Regulates entrance and exit of materialsCytoplasm- all the materials inside the cell- Cytosol – intracellular fluido Contains waste, nutrients, ions, proteinso Distributes via diffusion in the cello Glycogen is found in granules  goes to mitochondria for glycolysiso Also contains organelles Found everywhere (differ by location) Membranous (possesses plasmalemma) vs. non-membranous- Non-membranous ( in contact with the cytosol)o Cytoskeleton (microtubules) Membrane extensions with microtubules- ↑ surface area = ↑ absorption o Ribosomes (intracellular factories)Cilia- Anchored beneath cell surface- Exposed region completely covers plasmalemma - Function:o Moves fluid, secretions across cell surfacePlasmalemma- lipid bilayer [phospholipids, proteins, CHO (carbohydrate), steroids]- Isolates, protects cell- Regulates entrance and exit of materialsRibosomes- RNA & proteins- Protein synthesis- Form particular protein sequencesFixed ribosomes- Bound to Rough ER2- Produce protein within the cytosol- Enter the lumen (internal cavity of the ER)Free ribosomes- Scattered throughout the cytoplasm- Proteins made here enter the cytosol**Membranous Organelles- Mitochondria- Nucleuso Nuclear envelope, nucleus, nuclear pore- Smooth and Rough ERMitochondria (outer membrane surrounds entire organelle. ↑S.A = ↑ cellular respiration = ↑ ATP production)- Double membrane with inner folds (cristae)o Produce 95% of ATP for cell- Encloses metabolic enzymeso Matrix contains these metabolic enzymes- Mitochondria control its own growth and reproduction- # of mitochondria is dependent upon the individual cell’s energy demando RBC’s – no mitochondria presento Liver and skeletal muscle have a lot of mitochondriao # of mitochondria can increase with trainingMitochondria have 5 distinct compartments1. Outer mitochondrial membrane2. Intermembrane space 3. Inner mitochondrial membrane4. Cristae space (formed by the inner folds)5. Matrix1. Outer membrane (OM)- Encloses entire organelle- Many integral proteins (porins)o Allow certain molecules to diffuse freely- Disruption of the OM = cell deatho Intermembrane space leaks into cytosol- Associated with the ERo Via MAM (Mitochondrial-Associated ER Membrane)o Ca2+ signaling, lipid transferIntermembrane Space (IMS)- Between the outer and inner membrane- OM freely permeable to small moleculeso Small molecules in the IMS is the same as the molecules in the cytosol Same concentration as well3- Large proteins have specific sequences to cross the OM- Protein composition differs from the cytosolIntermembrane Space (IM)- No porins, highly impermeable- Contains proteins with specific functions:o redox reactions of oxidative phosphorylationo ATP synthase (ATP generator) (generated in the matrix)o Metabolic passage in and out of the matrix Via specific transport proteinsCristae- Skeletal muscles have mitochondria with more cristae because more ATP is needed Matrix- Enclosed by inner membrane- ATP is produced here- Lots of enzymes- Major Function:o Oxidation of pyruvate, fat acids, citric acid cycleNucleus- Control center for cellular operationo Controls synthesis of A LOT of proteinso Determines cell characteristics Up or down regulates proteinsNucleoplasm- Fluid contents of the nucleus- Ions enzymes, DNA/RNA nucleotides, proteins- DNA strands form chromosomes (chroma = color)o 46 chromosomes in humans, 23 pairs- Each chromosome contains DNA wound around histoneso Dividing cells = tightly coiled DNA wound around histone o Non-dividing cells = loosely coiled DNA (chromatin)Nucleosomes- DNA strands wound around histone- Contains DNA & RNA- rRNA synthesis, assembly or ribosomal subunitsNucleus- maintains the integrity of everythingNuclear genome- heredity information4- encoded in the DNA (RNA in viruses)o antigenic shift in influenza viruses- Genome sequencing, mouse models, (genetic strains) mapped using genomeNuclear envelope: membrane- Double lipid bilayer enclosing genetic materialo Also a physical barrier- 2 membranes: outer and innero Outter: continuous with Rough ERo Inner: Intermembrane proteinsER has 4 major functions1. Synthesis (CHO, steroids, lipids)2. Storage3. Transport4. DetoxGolgi Apparatus (G.A.)- Lysosome (digest): remove damaged organelles, pathogens - Peroxisome (degrade): fat catabolism. Neutralization of toxic compounds generated by fat catabolism58/31/2012Lysosomes (housekeeper)- Released from the G.A.- Lyse things/dissolve them- 3 ways lysosomes do worko Exocytosis- occurs at secretory vesicles  vesicles carry materials away from G.A.o Endocytosiso PhagocytosisLysosomes cont.- Reuses nutrients- Breaks down muscle cell contractive proteinso Autolysis usually goodo Can cause diseaseo Causes buildup of bad stuffPeroxisomes- Absorb, break down fatty acids- Enzymatic activity may form toxins H2O2- Most are found in the livero Remove and neutralize toxins (alcohol)Functions of the Plasmalemma (selectively permeable)- Physical isolation- Regulation of environmental exchange- Sensitivity- Structural support69/5/2012Bone ch. 5Osseous tissue (Connective Tissue)Bones provide structure, movement, and foundationBone composition- Bone  rigid- 1/3 made of collagen fibers / protein fibers (elastic)- 2/3 made of calcium phosphate/calcium carbonate- Flexible- Ca2+ strong but brittle / Collagen is weak but elastico Ca2+ + Collagen = strong and elastic. Periosteum (a weak skin that can be easily pulled off)- Outer surface of bone- Separates osseous tissueo Isolates/protects bone from surrounding tissueo Attachment for circulating nervous supply Attaches bone to CT network of the deep fascia (bone to muscle)o Not present where tendons, ligaments, and joint capsules attacho Participates in growth and repair- Covers most bone surfaces- Fibrous outer layer, cellular inner layer- Aids in attaching bone to tissues/ tendons to ligaments o tendons: (muscle to bone)o ligament: (bone to bone) - Interwoven w/ tendonous fibers that connect tendon to bone (made of collagen)o Tendonous/collagen fibers of Periosteum make up perforating/Sharpey’s fibers- “cement” tendon to the boneo This bond can break before the tendon snaps because the tendon is that strong Tendon is super strong- At synovial joints