effective study habits 1.develop a routine (time, place, no distractions, take breaks). 2.pay...
Post on 22-Dec-2015
215 views
TRANSCRIPT
Effective Study Habits1.Develop a routine (time, place, no distractions, take breaks).2.Pay attention to the schedule.3.In addition to notes write down details and specific examples provided in class.4.Interact!!5.Recap daily.6.Test yourself!7.Read!
Page 4
Copyright © 2010 Pearson Education, Inc.
Figure 4.1 Overview of four tissue types: epithelial, connective, muscle, and nervous tissues.
Nervous tissue: Internal communication• Brain, spinal cord, and nerves
Muscle tissue: Contracts to cause movement• Muscles attached to bones (skeletal)• Muscles of heart (cardiac)• Muscles of walls of hollow organs (smooth)
Epithelial tissue: Forms boundaries between different environments, protects, secretes, absorbs, filters• Skin surface (epidermis)• Lining of GI tract organs and other hollow organs
Connective tissue: Supports, protects, bindsother tissues together• Bones• Tendons• Fat and other soft padding tissue
Page 117
Cell Type
Epithelial 1. Squamous 2. Columnar 3. Cuboid
FunctionsA.Protection 1. Barrier against infection 2. Reduces dehydration 3. Reduces friction
a. cells sloughb. secretions (serous fluid,
mucous)B. Glandular secretionsC. Absorption
Locations? Pg 1.28
Copyright © 2010 Pearson Education, Inc.
Figure 4.2b Classification of epithelia.
Squamous (scale)
Cuboidal (glands)
Columnar(b) Classification based on cell shape. Page 119
Cells Simple Small 6-Sided (tightly
packed) Little Space *Highly MitoticAvascularNerve Endings
Copyright © 2010 Pearson Education, Inc.
Figure 3.5 Cell junctions.
Interlockingjunctionalproteins
Intercellularspace
Intercellularspace
Plasma membranesof adjacent cells
Microvilli
Intercellularspace
Basement membrane
Plaque
Linkerglycoproteins(cadherins)
Intermediatefilament(keratin)
Intercellularspace
Channelbetween cells(connexon)
(a) Tight junctions: Impermeable junctions prevent molecules from passing through the intercellular space.
(b) Desmosomes: Anchoring junctions bind adjacent cells together and help form an internal tension-reducing network of fibers.
(c) Gap junctions: Communicating junctions allow ions and small molecules to pass from one cell to the next for intercellular communication.
Pg 67Tight seal b/t cells
Areas of high friction or stress
Copyright © 2010 Pearson Education, Inc.
Figure 4.2b Classification of epithelia.
Squamous (scale)
Cuboidal glands
Columnar(b) Classification based on cell shape. Page 119
Cells Simple Small 6-Sided (tightly
packed) Little Space *Highly MitoticAvascularNerve Endings
Copyright © 2010 Pearson Education, Inc.
Figure 4.2a Classification of epithelia.
Stratified
Simple
Apical surface (free)
Basal surface
Apical surface
Basal surface
(a) Classification based on number of cell layers.
Pg 119
-Low wear & tear-Absorption & Filtration
Basement membrane
-High wear & tear
© 2013 Pearson Education, Inc.
Figure 4.3d Epithelial tissues.
Pseudostratified columnar epithelium
Function: Secrete substances, particularly mucus; propulsion of mucus by ciliary action.
Description: Single layer of cells of differing heights, some not reaching the free surface; nuclei seen at different levels; may contain mucus-secreting cells and bear cilia.
Photomicrograph: Pseudostratified ciliated columnar epithelium lining the human trachea (800x).
Cilia
Basement membrane
Pseudo-stratified epithelial layer
Location: Nonciliated type in male’s sperm-carrying ducts and ducts of large glands; ciliated variety lines the trachea, most of the upper respiratory tract.
Trachea
Pg 122
Copyright © 2010 Pearson Education, Inc.
Figure 4.3a Epithelial tissues.
(a) Simple squamous epithelium
Description: Single layer of flattenedcells with disc-shaped central nucleiand sparse cytoplasm; the simplestof the epithelia.
Function: Allows passage ofmaterials by diffusion and filtrationin sites where protection is notimportant; secretes lubricatingsubstances in serosae.
Location: Kidney glomeruli; air sacsof lungs; lining of heart, bloodvessels, and lymphatic vessels; liningof ventral body cavity (serosae).
Photomicrograph: Simple squamous epitheliumforming part of the alveolar (air sac) walls (125x).
Air sacs oflung tissue
Nuclei ofsquamousepithelialcells
Pg 120
Line cavities, cover organs, alveoli, B.V. , secretory
Copyright © 2010 Pearson Education, Inc.
Simple Squamous Apical View
© 2013 Pearson Education, Inc.
Figure 4.3c Epithelial tissues.
Function: Absorption; secretion of mucus, enzymes, and other substances; ciliated type propels mucus (or reproductive cells) by ciliary action.
Location: Nonciliated type lines most of the digestive tract (stomach to rectum), gallbladder, and excretory ducts of some glands; ciliated variety lines small bronchi, uterine tubes, and some regions of the uterus.
Description: Single layer of tall cells with round to oval nuclei; some cells bear cilia; layer may contain mucus-secreting unicellular glands (goblet cells).
Simple columnar epithelium
Basement membrane
Photomicrograph: Simple columnarepithelium of the small intestine mucosa (660x).
Mucus of goblet cell
Simple columnar epithelial cell
Microvilli
-Lines dig. and repro. Tracts-Microvilli-Absorption
Pg 121
Copyright © 2010 Pearson Education, Inc.
Figure 4.3b Epithelial tissues.
(b) Simple cuboidal epithelium
Description: Single layer ofcubelike cells with large,spherical central nuclei.
Function: Secretion andabsorption.
Location: Kidney tubules;ducts and secretory portionsof small glands; ovary surface.
Photomicrograph: Simple cuboidalepithelium in kidney tubules (430x).
Basementmembrane
Connectivetissue
Simplecuboidalepithelialcells
Pg 121
Cuboid = Glands
Copyright © 2010 Pearson Education, Inc.
Figure 4.3e Epithelial tissues.
(e) Stratified squamous epithelium
Description: Thick membranecomposed of several cell layers;basal cells are cuboidal or columnarand metabolically active; surfacecells are flattened (squamous); in thekeratinized type, the surface cells arefull of keratin and dead; basal cellsare active in mitosis and produce thecells of the more superficial layers.
Function: Protects underlyingtissues in areas subjected to abrasion.
Location: Nonkeratinized type formsthe moist linings of the esophagus,mouth, and vagina; keratinized varietyforms the epidermis of the skin, a drymembrane.
Photomicrograph: Stratified squamous epitheliumlining the esophagus (285x).
Stratifiedsquamousepithelium
Nuclei
Basementmembrane
Connectivetissue
Pg 123
High wear & tearSloughSkin (outer layer), openings & exits
© 2013 Pearson Education, Inc.
Figure 4.3d Epithelial tissues.
Pseudostratified columnar epithelium
Function: Secrete substances, particularly mucus; propulsion of mucus by ciliary action.
Description: Single layer of cells of differing heights, some not reaching the free surface; nuclei seen at different levels; may contain mucus-secreting cells and bear cilia.
Photomicrograph: Pseudostratified ciliated columnar epithelium lining the human trachea (800x).
Cilia
Basement membrane
Pseudo-stratified epithelial layer
Location: Nonciliated type in male’s sperm-carrying ducts and ducts of large glands; ciliated variety lines the trachea, most of the upper respiratory tract.
Trachea
Pg 121
-Lines most of Respiratory tract-Has Goblet Cells
Copyright © 2010 Pearson Education, Inc.
Figure 4.3f Epithelial tissues.
(f) Transitional epithelium
Description: Resembles both stratified squamous and stratified cuboidal; basal cells cuboidal or columnar; surface cells domeshaped or squamouslike, depending on degree of organ stretch.
Function: Stretches readily and permits distension of urinary organ by contained urine.Location: Lines the ureters, urinary bladder, and part of the urethra.
Photomicrograph: Transitional epithelium lining the urinary bladder, relaxed state (360X); note the bulbous, or rounded, appearance of the cells at the surface; these cells flatten and become elongated when the bladder is filled with urine.
BasementmembraneConnectivetissue
Transitionalepithelium
Pg 123
-withstand tension changes-lines bladder & ureters
90% of all cancers are associated with epithelial cells. Why?
Clicker Question: Which of the following statements regarding epithelial tissues are true?
1. Has a good blood supply.2. Food in the stomach would touch the apical surface of the epithelial tissue there.3. Simple arrangements of epithelia are associated with filtration and absorption.4. Pseudostratified epithelia consist of at least 2 layers of cells stacked on top of one another.
A. 1,2,4 B. 2,3,4 C. 1, 2, 3 D. 2,3