Cells Mostly microscopic –Light microscopy upto 1000x Passes light through E.g. typical plant & animal cells –Electron microscopy upto x Scans sample with electron beam E.g. molecules (DNA) Prokaryotic –Bacteria and bacteria-like Eukaryotic –Fungi, Protista, Plants, Animals

Prokaryotes vs. Eukaryotes Simpler Smaller size DNA without nucleus Cell wall & other crude protective layers Lack organelles Complex >10x larger DNA in nucleus Cell membrane –Some also have cell wall Membrane bound organelles –specialization

Nucleus Genetic control center DNA –Replicates during cellular division –Fibers = chromatin Sends instructions as RNA (in nucleolus) through pores –To synthesize proteins (writes amino acid sequence)

Endoplasmic Reticulum Rough ER Studded by ribosomes –Assembles proteins for further processing Membrane system –Continuous with nuclear membrane Creates compartments Acts as highway or conveyer belt

Smooth ER Continuous with Rough ER Lacks the ribosomes Uses enzymes to make lipids –In sex cells, SER makes sex hormones –In liver cells, SER detoxifies –In muscle cells, SER stores and releases Calcium for muscle contraction

Golgi apparatus Shipping / Receiving department –Receives proteins from ER, modifies, packages, labels for destination, within or outside of cell

Lysosomes – breakdown bodies RER packaged enzymes Golgi modified Digests: –Food in vacuole –Bacteria in blood –Damaged organelle (recycles)

Vacuoles Membranous sacks w/o digestive enzymes Carry food in Storage –Water –Chemicals –Waste –Pigments –Poisons

Contractile vacuoles Water regulation –Water continues to seep inside Osmotic properties and differences in concentrations –Pump out excess –Prevents cells from over- swelling or burst

Chloroplasts Photosynthesis = converts solar E to glucose Continuous double membrane/compartment system –Fluid stroma –disks or grana = solar power packs

Mitochondria Converts glucose (stored E) into cellular E (ATP) –Potential E to chemical E to Kinetic E –Via cellular respiration Double membrane & compartment system –Fluid matrix –Folds or Cristae to increase Surface Area

Cytoskeleton – structural proteins Microfilaments – cell structure & cell contraction Intermediate filaments – cell structure and anchoring Microtubule – organelle support & movement

Cilia & Flagella Locomotor microtubules Short, numerous Long less numerous

Cell Surfaces Cell wall, plasma membrane, or capsules Plant cell wall –Cellulose fibers for structure & support –E.g. wood is almost all cell wall material –Plasmodesmata for intercellular communication Animal cell membranes –Tight junctions = leakproof –Anchoring junctions = strength –Gap junctions = intercellular communication