Integumentary System: Tissues

Bellwork Describe a time when you saw a band play live. What type of instruments did they have? How were these instruments arranged on stage?

What advantages does this seating arrangement confer? Easy for conductor to control more effective function (sound) than if different instruments were randomly distributed among each other easier for individual instrumentalists within an instrument group to harmonize and cooperate

Would these same advantages be useful in the human body? Yes! How does the body achieve these advantages? Through organization of cells with similar structure and function into tissues. Tissue: groups of cells that are similar in structure and function.

Cell Specialization What is an example of a specialized cell? Muscle fiber What advantages does specialization confer? Perform specific function Work efficiently to perform function Join with like specialized cells (instrument section) Different types of specialized cells work together (entire symphony)

Tissue Types Think of 4 tissue types as parts of an airplane epithelium = covering = skin of aircraft connective = support = internal airframe muscle = movement = engine nervous = control = cockpit

Bellwork List and describe the geometry of three (3) types of Epithelial tissue. Where might we find these types? What do they do? Squamos – flattened – lining of hollow organs, body cavities, covering outer surfaces; function in filtration/protection Cuboidal – cube-shaped – lining of glands and some organs – function in secretion and absorption Columnar – tall and thin – lining of digestive tract – function in secretion/absorption

Epithelial Tissue

Where are epithelial cells found? Cover surfaces Cover organs Line hollow organs Line body cavities

Functions of epithelial cells Filtration Secretion Absorption Covers surface Protection

Characteristics of Epithelial Tissue Tightly packed: Little substance between cells Tightly bound to each other: close junctions Avascular: (not near blood for nutrients) Don’t conduct (like nerve cells) No blood vessels to provide nutrient supply Must use neighboring tissue for nutrients and waste

Characteristics of Epithelial Tissue 4. Thin a) Need to get nutrients b) when thick, they are dead (skin) 5. Have two surfaces: (Figure 5.1) a) basement membrane that cell sits on b) apical (free) surface

Figure 5.1

Pair Activity Several simple epithelial cells will be projected. In pairs and on a half-sheet of paper, discuss a) cellular geometry b) function that the cell might serve and why

Slide #1 Simple squamous

Slide #2 Simple cuboidal

Slide #3 Simple columnar

Slide #4 Simple cuboidal

Review 4 types of tissue Characteristics of epithelial tissue Where is epithelial tissue found? Functions of epithelial tissue

Compare and Contrast A. B. One layer of cells (A) Several layers of cells (B) B.

How are these cells different? B. A. pancake Circle, bricks, boxes C. D. Vertical, long, compact Puzzle pieces, vertical

Simple Squamous Where? Capillary, lines blood vessels Function? Filtration and exchange

Simple Cuboidal Where? Glands, ducts, nephron of kidney, ovaries Function? Secretion, absorption

Simple Columnar Where? Lines digestive tract from stomach to anus Function? Absorption, secretion, protection

Pseudostratified Columnar Where? Respiratory cells, looks stratified but is simple (sit on basement membrane) Function? Protection, secretion, mucus movement

Stratified Squamous Where? Epidermis of skin, oral cavity, esophagus Function? Protection against abrasion/impact/environmental factors

Stratified Cuboidal Rare Protection

Stratified Columnar Rare Protection, secretion

Transitional Epithelium Where? Bladder, lungs, kidney, where expansion is favorable Function? Change position with respect to each other, “distensibility”/expansion