4 Unit 1 Chapter 4

4 Unit 1 groups of cells with common role 4 basic types: Epithelial Connective Muscular Nervous

4 Unit 1 Cells close together – continuous sheets Cover surfaces & line cavities- always a free surface =Apical surface Basement membrane of connective tissue No blood vessels- avascular Have a nerve supply High capacity for cell division.

4 Unit 1 Simple epithelium = 1 layer of cells Stratified Epithelium= more than 1 layer of cells Cell Shapes = squamous, cuboidal, columnar, transitional (change shape)

4 Unit 1 Squamous= single layer of flat cells. Important for filtration (kidneys) or diffusion (lungs & capillaries) Called endothelium when lining heart, blood and lymphatic vessels Called mesothelium when in serous membranes

4 Unit 1 Simple Squamous Epithelium single layer of flat cells

4 Unit 1 Simple Squamous Epithelium single layer of flat cells

4 Unit 1 Simple Squamous Epithelium single layer of flat cells

4 Unit 1 Simple Cuboidal Epithelium cube shaped cells, rounded nuclei

4 Unit 1 Simple Cuboidal Epithelium cube shaped cells, rounded nuclei

4 Unit 1 Simple Columnar Epithelium May be ciliated or non-ciliated

4 Unit 1 Simple Columnar Epithelium May be ciliated or non-ciliated

4 Unit 1 Simple Columnar Epithelium May be ciliated or non-ciliated

4 Unit 1 Simple Columnar Epithelium May be ciliated or non-ciliated

4 Unit 1 Pseudostratified Columnar appears stratified: nuclei at various levels

4 Unit 1 Pseudostratified Columnar appears stratified: nuclei at various levels

4 Unit 1 Apical layer cells are flat Deep layers vary from cuboidal to columnar Cells in the basal layer divide and move upward toward apical surface Found in areas of surface wear & tear

Table 4.1f figure 1

Table 4.1f figure 2

4 Unit 1 Stratified Cuboidal Epithelium rare

4 Unit 1 Stratified Cuboidal Epithelium rare

4 Unit 1 Stratified Columnar Epithelium rare

4 Unit 1 Stratified Columnar Epithelium rare

4 Unit 1 Transitional Epithelium variable in appearance—cells can stretch

4 Unit 1 Transitional Epithelium variable in appearance—cells can stretch

4 Unit 1 Glandular Epithelium- Endocrine

4 Unit 1 Glandular Epithelium- Endocrine

4 Unit 1 Glandular Epithelium- Endocrine

4 Unit 1 Glandular Epithelium- Endocrine

4 Unit 1 Most abundant tissue type small cells far apart large amount of extracellular material (matrix) Often good blood supply – Found between other tissues Classified using matrix characteristics

4 Unit 1 Fibroblasts- present in several tissues secrete fibers & ground substance Macrophages- from monocytes Engulf bacteria & cell debris by phagocytosis Plasma cells- develop from B lymphocytes Make antibodies

4 Unit 1 Mast cells- near blood cells part of reaction to injury- histamine Adipocytes= fat cells or adipose cells Store triglycerides (fat)

4 Unit 1 Fluid, gel or solid plus protein fibers Ground substance-between cells and fibers Fibers- 3 types Collagen fibers: very strong & flexible Elastic fibers: smaller stretch and return to original length Reticular fibers: provide support & strength found in basement membranes & organ support

Figure 4.2

4 Unit 1 Areolar Adipose Reticular

Table 4.2a figure 1

Table 4.2a figure 2

Table 4.2b figure 1

Table 4.2b figure 2

Table 4.2c figure 1

Table 4.2c figure 2

4 Unit 1 Dense Connective tissue Dense regular Dense irregular Elastic

Table 4.2d figure 1

Table 4.2d figure 2

Table 4.2e figure 1

Table 4.2e figure 2

Table 4.2f figure 1

Table 4.2f figure 2

4 Unit 1 Dense network of collagen & elastic fibers embedded in chondroitin sulfate stronger than dense fibrous Cells = chondrocytes Occur singly or in groups Found in spaces called lacunae Surrounded by perichondrium No blood vessels or nerves

4 Unit 1 3 types Hyaline- fibers not easily visible Fibrocartilage- fibers visible Strongest type. E.g. in vertebral discs Elastic- chondrocytes in threadlike network e.g. ear cartilage

Table 4.2g figure 1

Table 4.2g figure 2

Table 4.2h figure 1

Table 4.2h figure 2

Table 4.2i figure 1

Table 4.2i figure 2

4 Unit 1 More dense matrix includes Calcium & phosphorus salts Details in Chapter 6

4 Unit 1 Blood- matrix = plasma More in chapter 14 Lymph- matrix like blood but with less protein More in chapter 17

4 Unit 1 large, elongated cells contractile cells Skeletal muscle tissue -named for location Cardiac muscle tissue- forms wall of heart Smooth muscle tissue –found in walls of hollow organs

4 Unit 1 Nerve cells & neuroglia Neurons- convert stimuli into nerve impulses and conduct them Neuroglia –do not generate nerve impulses. Serve supportive functions

4 Unit 1 4 types of body (not cell) membranes Mucous Membranes –line body cavities opening to exterior Secrete mucus Serous Membranes- surround moving organs Secrete serous fluid Synovial Membranes- line cavities of some joints. Secrete synovial fluid

4 Unit 1 New cells from stroma or parenchyma Epithelial cells originate from stem cells in defined areas of tissue layer Bone regenerates readily, cartilage poorly Muscular tissue can replace cells but slowly Nerve tissue is poorest at replacement although some stem cells seem to be available. Replacement from stroma –> scar tissue & functional loss.