Chapter 3 - Cells

Cell Theory1. A cell is the smallest unit of life.Chapter 3: The Cell2. Cells make up all living things.BIO 105Categories of cells Eukaryotic cells3. New cells only arise from preexisting,living cells.Categories of cells Prokaryotic cells1

Cell structure1. Plasma membrane2. Nucleus3. CytoplasmFluid mosaic modelPlasma membrane components Lipids– Phospholipids– pidOuter surfaceof plasmamembranePlasmamembrane ProteinsInner surfaceof plasmamembranePhospholipidbilayer CarbohydratesCytoplasmSurfaceproteinFilaments ofcytoskeleton2

Plasma membrane functionsMembrane TransportTwo types of forces are instrumental inmoving substances across the plasmamembrane.1. Passive2. ActiveSimpleDiffusionFacilitatedDiffusion3

OsmosisOsmosis – movement of solvent (i.e. H2O)molecules from an area of high to lowerconcentrationActive TransportEndocytosis4

EndocytosisExocytosis5

Nucleus Genetic materialNuclear envelopeNuclear poresNucleolusGenetic materialEndoplasmic Reticulum & RibosomesGolgi complexEndoplasmicreticulumNucleusRough endoplasmicreticulum (RER) hasribosomes attached to itssurface and is involved inmodifying proteins made bythe ribosomes.Smooth endoplasmicreticulum (SER) lacksribosomes and is involved indetoxifying certain drugs andin producing phospholipids forincorporation into membranes.6

LysosomesMitochondria7

Cytoskeleton Microfilaments Microtubules Intermediate filamentsCytoskeletonCytoskeleton - microtubulesMicrofilaments – main contractile elementsof the cytoskeletonImportant for muscle contraction & cell division8

Cell Metabolism9

What is metabolism? Sum of all the chemical reactionsoccurring in the body Catabolism anabolism Catabolism of glucose, amino acids, andfatty acids produces ATPMethods of ATP productionCellular Respiration1. Cellular respiration (aerobic)C6H12O6 6 O2 6 CO2 6 H2O Energy (ATP)2. Fermentation (anaerobic)10

Glycolysis (overview)Occurs in the cytoplasm of the cellInvolves the breakdown of a six-carbonmolecule (glucose) into two three-carbonmolecules (pyruvate)NAD & FAD are electron carriers11

Glycolysis (summary)Transition Reaction (overview)Start: one molecule of glucoseOccurs in the mitochondriaNet yield:2 pyruvate molecules2 ATP2 NADHInvolves the breakdown of the two pyruvatemolecules into two molecules of acetyl CoATransition Reaction summaryFor one molecule ofglucose:Start: 2 pyruvatesNet yield:2 Acetyl CoA2 CO22 NADH12

Citric Acid Cycle (overview)Occurs in the mitochondriaInvolves further processing of Acetyl CoAmolecules produced at the end of theTransition Reaction.Citric Acid Cycle (summary)For one molecule of glucose:Start: 2 Acetyl CoANet yield:2 ATP6 NADH2 FADH24 CO2Electron Transport ChainTakes place within mitochondriaUtilizes the electrons picked up by NAD and FADto make ATPElectron transport chain is a series of 5 proteinslocated along the inner mitochondrial membrane13

Electron Transport Chain(summary)The ETC produces ATP1 NADH ATP1 FADH2 ATPSo, how many ATP can be produced from a singlemolecule of glucose (under aerobic conditions)?14

Lactic acid fermentationWhat is the net yield of high energyproducts from fermentation?15

A cell is the smallest unit of life. 2. Cells make up all living things. 3. New cells only arise from preexisting, living cells. Categories of cells Eukaryotic cells Categories of cells Prokaryotic cells. 2 Cell structure 1. Plasma membrane 2. Nucleus 3. Cytoplasm Plasma membr