Ch. 4 Tissues (Study Guide) Flashcards
Define a “Tissue”
A collection of specialized cells and cell products that perform a specific function.
Name the four types of tissues in the body
- Epithelial
- Connective
- Muscular
- Neural
Describe the general characteristics of epithelial tissues
- Unique (Apical surface) exposed to the environment
- Closely packed & attached to each other
- A layer of cells that forms a superficial covering or an internal lining of a body cavity or vessel.
List the 2 main subtypes of epithelial tissue
- Glandular (Endocrine & Exocrine glands)
- Surface epithelium
What is an endocrine gland? Give examples of specific endocrine glands.
A gland that secretes hormones into the blood and interstitial fluid
EX: Thyroid, pituitary
What is an exocrine gland? Give examples of specific exocrine glands.
A gland that secretes onto the body or into a passageway connected to the exterior
EX: Oil, sweat
Describe the basic structure of an epithelial membrane, and list the 3 main types
found in the body.
Basic structure: combination of epithelial tissue attached to connective tissue. Connection occurs at the basement membrane.
3 types: Mucous, Serous, Cutaneous
Describe the structure, functions and locations of the specific epithelial membranes
found in the body.
- Mucous
- Structure: Lines body cavities that open to exterior environment.
- Function: Epithelial cells secrete mucous to moisten & protect surface.
- Location: Linings of digestive tract.
- Serous
- Structure: Two layers. Parietal (lines cavity wall) and Visceral (covers organs within cavity)
- Function: Epithelial cells secrete serous fluid, a watery fluid that lubricates surface of membranes to decrease friction.
- Location: Lines internal ventral body cavities and covers organs with the cavity. Pleura, Pericardium.
- Cutaneous (Skin)
- Structure: Dermis (connective layer) & epidermis (epithelial layer)
- Function: Covers and protects body surface from external environment.
- Location: Surface of body
Covering & lining epithelium is classified on the basis of:
Number of layers & cell shape
Define/describe the following:
a. Simple epithelium
b. Stratified epithelium
c. Pseudostratified epithelium
d. Squamous cells
e. Cuboidal cells
f. Columnar cells
g. microvilli
h. cilia
i. goblet cells
- Number of layers:
- simple: 1 layer of cells
- stratified: more than 1 layer of cells
- pseudostratified: looks like more than 1 layer but all cells contact basement membrane - Cell shape:
- Squamous: flat
- Cuboidal: cube shaped
- Columnar: tall columns
Microvilli and cilia can sit on top of cuboidal and columnar cells
Describe the structure, functions and locations of the following epithelial tissues:
a. simple squamous epithelial tissue
b. simple columnar epithelial tissue
c. stratified squamous epithelial tissue (keratinized and non-keratinized)
d. pseudostratified ciliated columnar epithelial tissue
a. simple squamous epithelial tissue
- Structure: single layer of cells, flat.
- Function: Reduces friction; controls vessel permeability; performs absorption and secretion.
- Location: Epithelia lining ventral body cavities; lining heart and blood vessels.
b. simple columnar epithelial tissue
- Structure: single layer of cells, tall columns
- Function: Secretion, absorption, some protection.
- Location: Lining of stomach, intestine, gallbladder, uterine tubes.
c. stratified squamous epithelial tissue (keratinized and non-keratinized)
- Structure: more than 1 layer of cells, flat
- Function: Provides physical protection against abrasion, pathogens and chemical attack.
- Location:
Keratinized: surface of skin
Non-keratinized: lining of mouth, throat, esophagus, rectum, anus and vagina.
d. pseudostratified ciliated columnar epithelial tissue
- Structure: only 1 layer but looks like more than 1, tall columns with cilia on top
- Function: protection, secretion, move mucus with cilia.
- Location: lining of nasal cavity, trachea and bronchi; portions of male reproductive tract.
Describe the general characteristics of connective tissues (CT)
- Cells differ depending on specific type of CT; (mesenchymal, fibroblasts, chondrocytes, osteocytes)
- Cells usually widely spaced with intercellular matrix between
- Usually well vascularized (exception: cartilage)
- Usually do not regenerate easily
- Repair ability varies depending on type of CT
What is the “matrix” of a connective tissue comprised of and why is it important to the tissue?
- Ground substance: varies in consistency from liquid, to gel-like, to solid, depending on specific CT.
- Protein fibers:
- Collagen: provides strength to tissue
- Elastic: provides elasticity
- Reticular: provides support to tissue
The Matrix of the tissue most directly determines the functional qualities of the tissue.
How does the ground substance of a tissue affect its function?
Ground substance varies in consistency from liquid, to gel-like, to solid, depending on specific CT in order to aid the specific function of the specific tissue.
Name the fibers that may be found in connective tissues and describe their functions.
Protein fibers:
- Collagen: provides strength to tissue
- Elastic: provides elasticity
- Reticular: provides support to tissue
