IPHY 3410 1st Edition Lecture 2 Outline of Last Lecture 1 Describe the functions and characteristics of plasma membrane ER Golgi lysosomes and mitochondria 2 Interpret the cell type based on the abundance of certain organelles 3 Describe the function of three specialized contacts junctions 4 Predict the location of specialized junctions based on their functions 5 Describe the function of three cytoskeletal elements 6 Compare and contrast the three cytoskeletal elements Outline of Current Lecture 1 List the four types of tissues found in the body 2 Describe the characteristics of epithelia plural of epithelium that distinguish them from other types of tissues 3 Describe structural classifications of epithelial tissues by layering simple or stratified 4 Illustrate epithelial tissues by shape squamous cuboidal or columnar 5 List epithelial types and their function 6 Predict which epithelial cell type you would expect to find in an organ given the tissue functions 7 Name the specialized structures associated with the lateral basal and apical surfaces of epithelial cells Current Lecture Cell Junctions join cells together Tight Junction prevents molecules from passing through intercellular space form a tight seal with Velcro dots Desmosomes bind adjacent cells at plaques o Strong prevent cell from being ripped apart o Linker proteins interdigitate with other linker proteins within intercellular space o Intermediate filaments span intracellular space to provide strength within cell Note Intercellular space between two cells Intracellular space within one cell Gap Junction allow for intercellular communication o Hollow protein cylinders channel connection between adjacent cells o Molecules can move quickly from cell to cell Tissues Tissue a group of similar cells and their extracellular matrix that perform a specific function Organ structure made up of two or more tissue types Tissue Types Epithelium covering and lining Connective support Nervous control Muscle movement These notes represent a detailed interpretation of the professor s lecture GradeBuddy is best used as a supplement to your own notes not as a substitute Epithelial Tissues Characteristics Highly cellular little extracellular space space between cells Lots of cell junctions seal strength and communication Polar distinct apical and basal regions o Apical top of cell o Basal foundation or base Sits on basement membrane for support o Basal lamina protein for surface of new cells o Reticular fibers connective tissue Avascular no direct blood supply Innervated have nervous connections Regenerative high capacity to replace cells ex skin Apical Surface Features Microvilli folds of plasma membrane of most epithelial tissue o Function maximize surface area for digestion and absorption Cilia whiplike motile extensions of cell surface o Function movement of mucus ex trachea Types of Epithelial Membranous majority of body coverings and linings Glandular produces glandular secretions Function Location Protection Skin Absorption Small Intestine Filtration Kidney Diffusion Lungs Chemoreception Nasal Cavity Membranous Epithelium Simple 1 layer thick Stratified more than 1 layer thick Squamous flattened cells Cuboidal rounded cube shaped cells Columnar tall cells Note cells are named based on the cell shaped found on the apical surface the more developed surface Types of Membranous Epithelium structure reflects function Simple Squamous o Diffusion lungs o Filtration kidney o Secretion serous membrane Simple Cuboidal o Absorption kidney o Secretion some glands Simple Columnar o May or may not be ciliated o Absorption GI tract o Movement mucus in lungs ciliated o Secretion mucus Pseudostratified Columnar o All sit on basement membrane o Secretion and movement of mucus in respiratory system o Usually ciliated o Goblet cells produce mucus Stratified Squamous o Protection skin and oral cavity o Can be keratinized or non keratinized Keratin is a protein for strength Stratified Cuboidal o 2 layers o Protection glandular ducts salivary glands Stratified Columnar o Protection male urethra o Secretion some glands o Not very common Transitional o Multiple layers that change shape when stretched o Unique found mainly in bladder o Contains tight and desmosome junctions Glandular Epithelium Gland collection of epithelial cells that make and secrete a substance Endocrine lacks ducts produce and secrete hormones into surrounding tissue blood vessels o Ex thyroid glands Exocrine secrete via ducts into body cavities or onto body surface o Ex salivary gland and duct Simple unbranched Compound branched Tubular tube shaped Alveolar rounder