Bio 101

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• Bio 101
• Laboratory 3
• Epithelial TissuesandIntegument

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Tissues

• Tissues to be examined under the microscope
• Epithelial Tissue (p. 67-74 Lab Manual)
• Integument (p. 91-104 Lab Manual)
• Connective Tissue (p. 74 - 81Lab Manual)
• We will be doing muscle and nervous tissues
  later in the semester
• Lab Guide (handout) for a checklist of
  tissues/structures you are responsible for
• Objectives
• Learn to recognize each of the tissue types under
  the light microscope by structure, not color, and
  how they are constructed
• Provide at least one example of where each tissue
  is found in the body on lab exam

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Tissues - Overview

• Recall that tissues are layers or masses of cells
  that have common functions
• The study of tissues is called?
• Usually the cells within tissues are separated by
  nonliving, intercellular materials that the cells
  produce.

Histology
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Sectioning and Staining of Tissues for Microscopy
Four steps in tissue preparation -
Fixation stabilizes and preserves the tissue -
Embedding converts the tissue into a solid form
which can be sliced ("sectioned") -
Sectioning (slicing) provides the very thin
specimens needed for microscopy (2-D) -
Staining provides visual contrast and may help
identify specific tissue components.
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Hematoxylin and Eosin (HE) Stain
Hematoxylin deep purple or blueEosin red
(pink) color
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Epithelial Tissue

• Widespread throughout body
• A covering and lining tissue
• Always has a free surface
• Underside of tissue is anchored to a basement
  membrane (nonliving layer)
• Lacks blood vessels
• Cells are tightly packed

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Epithelial Tissue

• - Epithelial tissues are classified by a
  combination of two characteristics
• - Cell shape
• Squamous (flat)
• Cuboidal (cube-shaped)
• Columnar (elongated rectangles)
• Layering (or stratification)
• Simple (single layer)
• Stratified (two or more layers)
• Pseudostratified (false stratification really
  one layer)
• Transitional (can change shape when stretched)

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Simple Squamous Epithelial Tissue
Free surface
Found lining air sacs of lungs, blood vessels,
ventral body cavities, kidney glomeruli,
lymphatic vessels
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Stratified Squamous Epithelium
Found as 1) outer layer of skin (keratinized,
non-mucous) 2) Mucous nonkeratinized linings in
esophagus, mouth, vagina
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Simple Cuboidal Epithelium
Simple cuboidal Found in kidney tubules, ducts
of sweat glands and other glands, surface of
ovary.
(Stratified cubioidal)
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Simple Columnar Epithelium
Note brush border on the free surface of simple
columnar cells and scattered goblet
(mucus-producing) cells
Found throughout digestive tract, uterine tubes,
some regions of uterus
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Pseudostratified Ciliated Epithelium
Found in trachea and most of the upper
respiratory tract.
Appears stratified because nuclei are located at
different levels However, ALL cells reach the
basement membrane Note how different cilia look
as compared to microvilli of brush border on
simple columnar cells
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Transitional Epithelium
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Integumentary System
The Integument is an Organ. Why?
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Integumentary System
From http//www.lab.anhb.uwa.edu.au/mb140/CorePag
es/Integumentary/Integum.htmsebaceous
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Integumentary System
From http//www.lab.anhb.uwa.edu.au/mb140/CorePag
es/Integumentary/Integum.htmsebaceous
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Integumentary System
From http//www.lab.anhb.uwa.edu.au/mb140/CorePag
es/Integumentary/Integum.htmsebaceous
Sebaceous glands
Hair follicles
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Integumentary System
From http//www.lab.anhb.uwa.edu.au/mb140/CorePag
es/Integumentary/Integum.htmsebaceous
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Integumentary System
From http//www.lab.anhb.uwa.edu.au/mb140/CorePag
es/Integumentary/Integum.htmsebaceous
Sweat gland
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Light Microscope View of Sweat Glands
From Martini, Anatomy Physiology, Prentice
Hall, 1998
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Review

• Epithelium
• Simple squamous single layer of flattened cells
• Simple cuboidal single layer of square cells
• Simple columnar single layer of rectangular
  cells may have goblet (mucus) cells
• Stratified squamous stacked squamous cells
• Pseudostratified ciliated columnar
• Look like stratified by they are not
• Have cilia
• Have goblet cells

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Review

• Integument
• Layers
• Epidermis, dermis skin
• Subcutaneous (hypodermis, superficial fascia)
• Accessory structures
• Hair follicles in which hair grows
• Sebaceous glands
• Look fatty
• Look similar to adipose tissue except nucleus is
  in center of cell
• Usually found in a cluster of cells attached to a
  hair follicle
• Sweat glands
• Much more solid in appearance than sebaceous
  glands
• Ducts of sweat glands are lined with simple
  cuboidal epithelium
• Section through ducts gives varied appearance,
  i.e., some are circular, some longitudinal, some
  oblique

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What you should do in lab today

• Using the microscope and the slide boxes
• Look at the slides listed on your Laboratory
  Guide (handed out in first lab) for
• Epithelial tissue
• Integumentary System
• BE SURE you can recognize each of the tissue
  types listed in your Laboratory Guide check off
  ONLY after you can recognize a tissue
• KNOW at least one place in the body where each of
  the tissue types is found for lab exam
• Get tested on slides for today (identification
  only not location in body)

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For Next Lab

• On Your Own Do the Review Sheet Exercises for
  Exercise 6 and 7
• Tissue Structure and Function - General review,
  p. 85
• Epithelial Tissue, pp. 85 87
• Integument, pp. 101 - 103
• Read ahead Connective Tissues
• Pages 74 through 81 in your Laboratory Manual