LE Plasma membrane Cytoplasm DNA Ancestral prokaryote Endoplasmic reticulum Nuclear envelope Infolding of plasma membrane Engulfing of aerobic heterotrophic prokaryote Nucleus Cell with nucleus and endomembrane system Mitochondrion Engulfing of photosynthetic prokaryote in some cells Plastid Mitochondrion Ancestral heterotrophic eukaryote Ancestral photosynthetic eukaryote

MITOCHONDRIA Mitochondrion Intermembrane space Matrix 100 nm Free ribosomes in the mitochondrial matrix FUNCTION: GLUCOSE IS TURNED INTO ATP BY A PROCESS CALLED CELLULAR RESPIRATION.

SURFACE AREA REACTIONS MITOCHONDRIA AND CHLOROPLASTS HAVE FOLDED INNER MEMBRANES TO INCREASE THE SURFACE AREA TO FIT MORE ENZYMES (PROTEINS). RESPIRATION AND PHOTOSYNTHESIS INVOLVE PASSING SUBSTRATES ALONG ENZYME (PROTEIN) PATHWAYS ON A MEMBRANE.

PLASTIDS ONLY IN PLANTS LEUCOPLAST: – COLORLESS OR CLEAR – STORAGE SACS – EXAMPLE: AMYLOPLASTS WHICH STORE STARCH. CHROMOPLAST: – COLORED – EXAMPLE: CHLOROPLAST (GREEN- CONTAINS CHLOROPHYLL)- PHOTOSYNTHESIS

CHLOROPLAST Chloroplast Ribosomes Thylakoid 1 µm FUNCTION: CONVERT SOLAR ENERGY INTO CHEMICAL ENERGY (PHOTOSYNTHESIS)

ORGANELLES THAT ARE NOT MADE OF MEMBRANE RIBOSOMES: CLUMPS OF rRNA.... CYTOSKELETON (support, mobility, regulation) – MICROFILAMENTS – MICROTUBULES CILIA FLAGELLA CENTRIOLES – INTERMEDIATE FILAMENTS CELL WALL GLYCOCALYX (CELL COAT)

MICROFILAMENTS FUNCTION: – STRUCTURAL SUPPORT FOR THE CELL (NETWORK JUST INSIDE THE CELL MEMBRANE) – CELL MOBILITY – PSEUDOPODAL MOVEMENT (PUSH OUT CELL MEMBRANE) – CYTOPLASMIC STREAMING STRUCTURE – STRANDS OF ACTIN PROTEINS INTERACT WITH MYOSIN PROTEIN TO MOVE THE CELL. – SOLID RODS

LE 6-27a Muscle cell Actin filament Myosin filament Myosin arm Myosin motors in muscle cell contraction

LE 6-27b Cortex (outer cytoplasm): gel with actin network Amoeboid movement Inner cytoplasm: sol with actin subunits Extending pseudopodium

LE 6-27c Nonmoving cytoplasm (gel) Cytoplasmic streaming in plant cells Chloroplast Streaming cytoplasm (sol) Cell wall Parallel actin filaments Vacuole

MICROTUBULE Microtubule Microfilaments 0.25 µm

MICROTUBULES COILED TUBES MADE OF TUBULIN PROTEIN CAN FORM VERY LONG TUBES OR SHORT ONES THAT CAN EXPAND. PROVIDE: – SHAPE – SUPPORT – TRACKS THAT ORGANELLES CAN MOVE ALONG MAKE UP: – CILIA – FLAGELLA. – CENTRIOLES – BASAL BODIES

CENTRIOLES 0.25 µm Microtubule Longitudinal section of one centriole Microtubules Cross section of the other centriole FUNCTION: MOVE CHROMOSOM ES TO OPPOSITE SIDES OF THE CELL DURING MITOSIS (CELL DIVISION STRUCTURE: 9 TRIPLET ARRANGEMENT OF MICROTUBULES

CILIA &FLAGELLA 0.5 µm Microtubules Plasma membrane Basal body Plasma membrane 0.1 µm Cross section of basal body Triplet Outer microtubule doublet 0.1 µm Dynein arms Central microtubule Cross-linking proteins inside outer doublets Radial spoke 9-2 DOUBLET ARRANGEMENT OF MICROTUBULES.. FUNCTION: MOVEMENT (PARAMECIUM), FILTER DUST IN THE TRACHEA, ETC. BASAL BODY (POINT OF ATTACHMENT BETWEEN FLAGELLUM & CYTOPLASM) HAS A 9 TRIPLET ARRANGEMENT

CEL L WAL L Central vacuole of cell Plasma membrane Secondary cell wall Primary cell wall Middle lamella 1 µm Central vacuole of cell Central vacuole Cytosol Plasma membrane Plant cell walls Plasmodesmata

CELL WALL FUNCTION: – PROTECTION – STRUCTURE – PREVENTS THE UPTAKE OF EXCESS WATER STRUCTURE – MICROFIBRILS MADE OF CELLULOSE – OTHER POLYSACCHARIDES AND PROTEINS (VARIES) – PLASMODESMATA: INTERCELLULAR JUNCTION BETWEEN PLANT CELLS THAT ALLOW CYTOPLASM, SOLUTES, ECT. TO PASS FROM ONE CELL TO ANOTHER. (CELLULR COMMUNICATION)

Tight junctions prevent fluid from moving across a layer of cells Tight junction 0.5 µm 1 µm 0.1 µm Gap junction Extracellular matrix Space between cells Plasma membranes of adjacent cells Intermediate filaments Tight junction Desmosome Gap junctions INTERCELULAR JUNCTIONS: ANIMAL CELLS