Chapter 3b Compartmentation Cells and Tissues 2013 Pearson Education Inc Golgi Apparatus Golgi Complex Stacked membranes surrounded by vesicles Modifies protein from rough ER Packages proteins into vesicles 2013 Pearson Education Inc Figure 3 4 2h REVIEW Cell Structure Golgi Apparatus Vesicle Cisternae The Golgi apparatus consists of a series of hollow cured sacs called cisternae stacked on top of one another and surrounded by vesicles The Golgi apparatus participates in protein modification and packaging Cytoplasmic Vesicles Secretory vesicles Released from cell Storage vesicles Lysosomes Enzymes to degrade bacteria or old organelles Acidic interior Peroxisomes Enzymes to degrade long chain fatty acids and toxic foreign molecules Generate hydrogen peroxide 2013 Pearson Education Inc Figure 3 4 1d REVIEW Cell Structure Lysosomes Lysosomes are small spherical storage vesicles that contain powerful digestive enzymes Figure 3 4 1c REVIEW Cell Structure Peroxisomes Peroxisomes contain enzymes that break down fatty acids and some foreign materials Nucleus Nuclear envelope two membranes Nuclear pore complex Chromatin DNA and associated proteins Nucleoli Control RNA synthesis 2013 Pearson Education Inc Figure 3 4 2j REVIEW Cell Structure Nucleus Nuclear envelope Nucleolus Nuclear pores The nucleus is surrounded by a double membrane nuclear envelope Both membranes of the envelope are pierced here and there by pores to allow communication with the cytoplasm The outer membrane of the nuclear envelope connects to the endoplasmic reticulum membrane In cells that are not dividing the nucleus appears filled with randomly scattered granular material composed of DNA and proteins Usually a nucleus also contains from one to four larger dark staining bodies of DNA RNA and protein called nucleoli Figure 3 7 Protein synthesis Nucleus mRNA DNA Endoplasmic reticulum Nuclear pore Ribosome Growing amino acid chain Peroxisome Targeted proteins Cytosolic protein Mitochondrion mRNA is transcribed from genes in the DNA Transport vesicle Retrograde Golgi ER transport Golgi apparatus Golgi mRNA leaves the nucleus and attaches to cytosolic ribosomes initiating protein synthesis Some proteins are released by free ribosomes into the cytosol or are targeted to specific organelles Ribosomes attached to the rough endoplasmic reticulum direct proteins destined for packaging into the lumen of the rough ER Proteins are modified as they pass through the lumen of the ER Transport vesicles move the proteins from the ER to the Golgi apparatus Golgi cisternae migrate toward the cell membrane Lysosome or storage vesicle Golgi apparatus Cell membrane Cytosol Extracellular fluid Secretory vesicle Some vesicles bud off the cisternae and move in a retrograde or backward fashion Some vesicles bud off to form lysosomes or storage vesicles Other vesicles become secretory vesicles that release their contents outside the cell Primary Tissue Types Epithelial Connective Muscle Neural nerve 2013 Pearson Education Inc Extracellular Matrix Synthesized and secreted by cells Proteoglycans Glycoproteins Insoluble protein fibers Examples collagen fibronectin laminin Strength Anchor cells to matrix for communication 2013 Pearson Education Inc Cell Junctions and CAMs Cell to cell Gap junction communicating junction Tight junction occluding junction Anchoring junction Cell cell with cadherins Adherens junctions Desmosomes Cell matrix with integrins Hemidesmosomes Focal adhesions 2013 Pearson Education Inc Table 3 3 Major Cell Adhesion Molecules CAMs Figure 3 8a ESSENTIALS Cell Junctions CELL JUNCTIONS Function Communicating Occluding Anchoring Location Type Cytoskeleton fiber Matrix protein Cell cell junctions Cell matrix junctions Gap junction Tight junction Adherens junction Desmosome Focal adhesion Hemi desmosome Membrane protein Connexin Claudin occludin Cadherin Integrin Actin Actin Intermediate filaments Actin intermediate Keratin filaments Fibronectin and other proteins Laminin Figure 3 8b ESSENTIALS Cell Junctions Cytosol Connexin proteins Intercellular space Cell membrane Cell 1 Cell 2 Gap junctions are communicating junctions Clusters of gap junctions Freeze fracture of cell membrane Figure 3 8c ESSENTIALS Cell Junctions Claudin and occludin proteins Cytosol Intercellular space Cell membrane Cell 1 Cell 2 Tight junctions are occluding junctions Tight junctions prevent movement between cells Adherens junction Figure 3 8d ESSENTIALS Cell Junctions Cadherin proteins Plaque glycoproteins Intermediate filament Cell membrane Intercellular space A desmosome is a cell to cell anchoring junction Tight junctions prevent movement between cells Adherens junction Desmosomes anchor cells to each other Epithelial Tissue Structure One or more layers of epithelial cells Separated from underlying tissue by basal lamina or basement membrane Two types Sheets of cells lining body surfaces Secretory epithelia 2013 Pearson Education Inc Figure 3 9c ESSENTIALS Epithelial Tissue Epithelial cells attach to the basal lamina using cell adhesion molecules Basal lamina basement membrane is an acellular matrix layer that is secreted by the epithelial cells Underlying tissue Most epithelia attach to an underlying matrix layer called the basal lamina or basement membrane Epithelial Tissue Classified Simple or stratified Squamous cuboidal columnar Layering Shapes Function secretory Exchange transporting ciliated protective 2013 Pearson Education Inc Figure 3 10 ESSENTIALS Types of Epithelia Figure 3 9b ESSENTIALS Epithelial Tissue Integumentary System Respiratory system This diagram shows the distribution of the five kinds of epithelia in the body outlined in the table above Circulatory system Digestive system Urinary system Cells Musculo skeletal system Reproductive system KEY Secretion Exchange Figure 3 10a ESSENTIALS Types of Epithelia Exchange Epithelium The thin flat cells of exchange epithelium allow movement through and between the cells Capillary epithelium Blood Capillary Pore Extracellular fluid Figure 3 10e ESSENTIALS Types of Epithelia Transporting Epithelium Transporting epithelia selectively move substances between a lumen and the ECF Lumen of intestine or kidney Apical membrane Microvilli Tight junctions in a transporting epithelium prevent movement between adjacent cells Substances must instead pass through the epithelial cell crossing two phospholipid cell membranes as they do so Basolateral membrane Transporting epithelial cell Extracellular fluid