1. Cell Physiology

5. General Cell Structure & Function Function Structure Component Surrounds, holds cell together & gives its form; controls passage of materials into & out of cell Membrane composed of double layer of phospholipids in which proteins are embedded Plasma (cell) membrane Serves as matrix substance in which chemical reactions occur. Fluid, jellylike substance b/w cell membrane & nucleus in which organelles are suspended Cytoplasm Supports nucleus & controls passage of materials b/w nucleus & cytoplasm Produces ribosomal RNA for ribosomes Contains genetic code that determines which proteins (including enzymes) will be manufactured by the cell Double-layered membrane that surrounds nucleus, composed of protein & lipid molecules Dense nonmembranous mass composed of protein & RNA molecules Fibrous strands composed of protein & DNA Nucleus: - Nuclear envelope - Nucleolus - Chromatin

9. Plasma Membrane (continued)

17. Cytoplasm, Organelles, Nucleoli (continued)

20. Cytoplasmic Organelles: Structure & Function Function Structure Component Agranular (smooth) ER metabolizes nonpolar compounds & stores Ca 2+ in striated muscle cells; granular (rough) ER assists in protein sysnthesis System of interconnected membrane-forming canals & tubules Endoplasmic reticulum Synthesize proteins Granular particles composed of protein & RNA Ribosomes Synthesizes carbohydrates & packages molecules for secretion. Secretes lipids & glycoproteins Cluster of flattened membranous sacs Golgi complex Release energy from food molecules & transform energy into usable ATP Membranous sacs w folded inner partitions Mitochondria Digest foreign molecules & damaged organelles Membranous sacs Lysosomes

25. Cytoplasmic Organelles: Structure & Function (continued) Function Structure Component Contain enzymes that detoxify harmful molecules & break down hydrogen peroxide Spherical membranous vesicles Peroxisomes Helps to organize spindle fibers & distribute chromosomes during mitosis Nonmembranous mass of 2 rodlike centrioles Centrosome Store & release various substances within the cytoplasm Membranous sacs Vacuoles Support cytoplasm & function as cytoskeleton, transport materials within the cytoplasm Thin, hollow tubes Microfilaments & microtubules Move particles along cell surface, or move the cell Minute cytoplasmic projections that extend from the cell surface Cilia & flagella

29. Cell Nucleus

34. Tight junction 0.5 µm 1 µm Desmosome Gap junction Extracellular matrix 0.1 µm Plasma membranes of adjacent cells Space between cells Gap junctions Desmosome Intermediate filaments Tight junction Tight junctions prevent fluid from moving across a layer of cells