Derm Flashcards
How many types of human tissue are there?
4
What are the functions muscle tissue?
(a)Generates the physical force to make the body structures move
(b)Arranged in bundles
(c)Contractile cells that provide the ability to move the body in three dimensions
(d)Well supplied with blood vessels (lots of energy & waste requirements).
What are the functions of nervous tissue?
(a)Generates the physical force to make the body structures move
(b)Arranged in bundles
(c)Contractile cells that provide the ability to move the body in three dimensions
(d)Well supplied with blood vessels (lots of energy & waste requirements).
What are the functions of epithelial tissue?
1)Covers body surfaces; lines body cavities, hollow organs and ducts (tubes);and forms glands
What are the functions of connective tissue?
(a)Protects and supports the body and its organs
(b)Binds organs together
(c)Stores energy reserves as fat
(d)Provides immunity
What do cell junction do?
(1)They provide contact or adhesion between neighboring cells or between a cell and extracellular matrix.
(2)They maintain paracellular barrier of epithelia (barrier in between cells) and control transport of materials or signals between cells (paracellular transport).
(3)Cell junctions are dense in epithelial tissues because the tissue needs to maintain both strength and integrity in a wide variety of conditions.
What do tight junctions do?
Form barrier against water and antigens passing between individual epithelial cells.
What do ahderens junctions do?
Cell-cell adhesions continuously assembled & disassembled so cells canrespond changes in their microenvironment.
What do desmosomes do?
Form stable adhesive junctions between cells.
What do gap junctions do?
Allows various molecules & electrical signals to pass freely between cells
What do Hemidesmosomes do?
Facilitate the stable adhesion of basal epithelial cells to the underlying basementmembrane.
What is epithelial tissue broadly categorized as?
(a)Covering and lining epithelium
(b)Glandular epithelium.
What is the apical layer of epithelial tissue?
Most superficial layer of cells
What is the basal layer of epithelial tissue?
Deepest layer of the cells
What is the basement membrane?
(a)Thin extracellular structure composed mostly of protein fibers
(b)Located between the epithelium and underlying connective tissue layer
(c)Helps to bind and support the epithelium
What are the 2 ways of classifying epithelial tissue?
(1)Morphology- Classification of epithelial cells based on shape
(2)Stratification- Classification of epithelial cells based on number of layers.
Describe squamous epithelium?
(1)Thin, flat shape allows rapid passage of substances through them
(2)Can be keratinized or non-keratinized; “wet” or “dry” depending on their location inthe body
(3)Found in areas such as the lining of the esophagus, mouth and cervix
Describe cuboidal epithelium?
(1)Tall as they are wide and shaped like cubes or hexagons
(2)Frequently have microvilli at apical surface
(3) Function in either secretion or absorption
(4) Found in areas such as the salivary glands and thyroid follicles
Describe columnar epithelium
(1) Taller than they are wide
(2) Protect underlying tissues
(3) Apical surfaces may have cilia or microvilli
(4) Often specialized for secretion and absorption
(5) Lines most organs of the GI tract, respiratory tract, and fallopian tubes
Describe transitional epithelium.
(1) Able to change shape from flat to cuboidal and back depending on tension & distention of tissue.
(2) Useful for organs such as the urinary bladder, when it is stretching (distend) to a larger size and then as it collapses to a smaller size.
