Chapter 4: Tissues

1
Chapter 4 Tissues

• Essential Questions
• What are tissues?
• What are the 4 main categories of tissues?

2
Word Parts important for Tissues

• Adip(o)- Fat
• -crine To Secrete
• Endo- Within
• Exo- Outside
• Hist- Tissue
• Lupus Wolf
• Macro- Large

• Multi- Many
• Path- Disease
• Pseudo- False
• Squam- This
• Strat- Layer
• Uni- One
• Vasc- Blood
• Vessel

3
Tissue Definitions

• Tissue group of cells with similar structure
  function
• Histology study of the structure function of
  tissues
• Pathology study of disease

4
Types of Tissues

• Epithelial
• for covering or lining
• Ex. skin
• Connective
• for connection, bind, support, transport
• Ex. bone, blood, tendons cartilage, fat
• Muscular
• for Skeletal Digestive Movement, Blood
  Pressure
• Ex. skeletal, smooth, cardiac
• Nervous
• communication of impulses
• Ex. brain, spinal cord, sensory, motor

5
Epithelial Tissue

• Essential Question
• What are the characteristics of common types of
  epithelial tissue?

6
General Features of Epithelial Tissue

• Consists mostly of closely packed cells
• Penetrated by NO blood vessels so therefore it is
  avascular
• Does have the capacity to undergo mitosis
• Surface tissue so it attaches to underlying
  connective tissue by the basement membrane

7
Classifying Epithelial Tissue

• Classified by Shape
• Squamous flat cells, attach to others like tiles
• Cuboidal thicker shaped like cubes
• Columnar tall cylindrical
• Transitional range in shape from flat to
  columnar
• Classified by Layers
• Simple single layer
• Stratified 2 or more layers
• Pseudostratified 1 layer but appears to be
  several layers (not all cells reach surface)

8
Examples of Shapes
Cuboidal
Squamous
Transitional
Columnar
9
Examples of Layers
Simple
Stratified
Pseudostratified
10
Most Common Types of Epithelium

• A Simple Squamous
• lines air sacs of lungs
• thin cells required for diffusion of gases
• Stratified Squamous
• lines mouth
• present on outer surface of skin (epidermis)
• B Simple Cuboidal
• single layer of cube-shaped cells
• found in kidneys some glands

11
Most Common Types of Epithelium

• C Simple Columnar, Nonciliated
• lines inner surface of the stomach intestine
• D Simple Columnar, Ciliated
• line upper respiratory passageways
• F Pseudostratified Columnar
• not a true stratified layer
• E Transitional
• lines urinary tract
• permits stretching
  

12
3 Modifications of Epithelial Lining of the
Intestine

• Microvilli
• fingerlike projections that increase the surface
  area (more digestion)
• Goblet Cells
• columnar cells that secrete mucus
• Cilia
• small hairlike structures

13
Glands

• A gland is a single cell or group of epithelial
  cells adapted for secretion
• The 2 types of glands are
• Exocrine glands
• Endocrine glands

14
Glands in Detail

• The products of exocrine glands are secreted into
  ducts that lead directly or indirectly to the
  outside of the body
• Secrete sweat, oil, mucus, and digestive enzymes
• Endocrine glands secrete hormones such as
  testosterone, insulin, thyroxine.