Ch 5 Test Yourself Flashcards
What are the four primary types of tissue?
Epithelial, connective, muscle, and nervous
What is histology?
Histology is the study of the microscopic structures of tissues and organs.
List seven functions performed by epithelial cells.
- Protect, cover, and line other tissues
- Filter biochemical substances
- Absorb nutrients
- Provide sensory input
- Manufacture secretions
- Manufacture excretions
- Act as an interface layer that separates and defines the beginning and ending of different types of tissues
What four attributes characterize epithelial tissue in general?
- Epithelial cells are polar
- Epithelial cells have lateral surfaces connected by junctional complexes
- All epithelial cells lack blood vessels or capillaries
- Most epithelial cells are innervated
List four types of cellular junctions.
How does the basement membrane act as a partial barrier between the epithelial cell and the underlying connective tissue?
Oxygen and nutrient molecules diffuse through the basement membrane from capillaries in the underlying connective tissue.
Why do some epithelial cells have cilia and microvilli?
Microvilli increase surface area for absorption; cilia enable efficient transport of material.
What does simple epithelial tissue mean?
A single layer of epithelial cells.
What does stratified epithelial tissue mean?
More than one layer of cells.
What are the three basic shapes of epithelial cells?
Squamous, cuboidal, and columnar.
Where can simple squamous epithelium be found?
Inner lining of the lung and in the filtration membranes of kidneys.
Where can simple cuboidal epithelium be found?
On the surface of ovaries, in the secretory portions of glands, and in the lining of ducts.
Where can simple columnar epithelium be found?
Lining the length of the gastrointestinal tract.
Where can stratified squamous epithelium be found?
Lining the mouth, esophagus, vagina, and rectum.
Where can pseudostratified columnar epithelium be found?
In the respiratory tract and in portions of the male reproductive tract.
Where can transitional epithelium be found?
In portions of the urinary tract where great changes in volume occur.
What is a gland?
A cell or group of cells that has the ability to manufacture and discharge a secretion.
How do glands develop embryologically?
Multicellular glands form from the infolding of a layer of epithelial cells.
What is the difference between endocrine and exocrine glands?
- Endocrine glands: No ducts, secrete hormones into bloodstream
- Exocrine glands: Possess ducts, discharge secretions locally
Where are goblet cells found?
Interspersed among columnar cells in the respiratory and digestive tracts.
What do goblet cells produce?
Mucin, which becomes mucus when combined with water.
How are multicellular exocrine glands constructed?
Consist of a secretory unit and a duct carrying the secretion.
Describe merocrine glands.
Secrete via exocytosis without damaging the secretory cells.
Describe apocrine glands.
Release secretions by pinching off the apex of the cell.
Describe holocrine glands.
Release secretions by destroying the entire secretory cell.
How are serous and mucous secretions different?
- Serous: Watery, high enzyme concentration
- Mucous: Thick, viscous, composed of glycoproteins
How are connective tissue and epithelial tissue similar?
Both may form membranes in the body.
What are the three basic constituents of connective tissue?
Extracellular fibers, ground substance, and cells.
List seven functions of connective tissue.
- Forms metabolic and structural connections
- Forms a protective sheath around organs
- Helps insulate the body
- Acts as a reserve for energy
- Provides structural support
- Composes the medium that transports substances
- Plays a role in healing and controlling microorganisms
What are GAGs?
Glycosaminoglycans, ground substance in soft connective tissue.
What role do GAGs play in connective tissue?
Help orient the formation of fibers during healing.
Compare collagenous fibers, reticular fibers, and elastic fibers.
- Collagenous: Strong, thick, provide tensile strength
- Reticular: Thin, branched, support highly cellular organs
- Elastic: Coiled, stretchable, found in tissues subject to stretching
What are fibroblasts?
Large, irregularly shaped cells that manufacture and secrete fibers and ground substance.
What are transient cells in connective tissue?
- Leukocytes
- Mast cells
- Macrophages
What is the common term for adipose tissue?
Fat
How is brown fat different from white fat?
Brown fat is involved in heat production; white fat stores energy.
What are the two broad categories of connective tissue?
Connective tissue proper and specialized connective tissue.
What happens to adipocyte cells as they fill with lipid?
The organelles and nuclei are pushed to one side, and the cells become large spheres with eccentrically placed nuclei. The cytosol is compressed into a thin rim surrounding the lipid droplet.
What is the appearance of adipose tissue under microscopic examination?
It has a ‘chicken wire’ appearance due to the lipid content being extracted during tissue preparation.
What is brown adipose fat and its role?
Brown adipose fat is a specialized form of adipose tissue found in newborns and hibernating animals, playing an important part in temperature regulation and heat production.
How does the cytoplasm of brown fat differ from white fat?
In brown fat, the cytoplasm is clearly visible and lipid is stored in multiple small vesicles rather than a single large droplet.
What is a key feature of brown fat relating to energy?
Energy from lipid oxidation and electron transport is dissipated as heat, not ATP.
Why does brown fat appear dark under microscopy?
It contains an exceptionally high number of mitochondria that become darkly stained.
What are the three subtypes of dense connective tissue?
- Dense regular
- Dense irregular
- Elastic
What are three examples of specialized connective tissue?
- Cartilage
- Bone
- Blood
How is cartilage similar to connective tissue proper?
It is composed of cells, fibers, and matrix.
What is a key difference between cartilage and dense connective tissue?
Cartilage is more rigid than dense connective tissue.
What limits the thickness of cartilage?
Nutrients diffuse from the surrounding perichondrium through the matrix to the chondrocytes.
What is the primary reason cartilage is slow to heal?
It is avascular.
Describe hyaline cartilage.
The most common type of cartilage, composed of closely packed collagen fibers, tough but more flexible than bone.
What distinguishes elastic cartilage from hyaline cartilage?
Elastic cartilage contains an abundance of elastic fibers forming dense branching bundles.
Where is fibrocartilage typically found?
Merged with hyaline cartilage and dense connective tissue, such as in the spaces between vertebrae.
What are the two basic cell types that make up neural tissue?
- Neurons
- Supporting neuroglial cells
What is the most important function of neural tissue?
To receive and transmit electrical and chemical signals throughout the body.
What portion of a serous membrane covers the outer surface of organs?
The visceral layer.
What is an effusion?
The escape of fluid from normal vessels into a body cavity.
What is ascites?
The presence of an effusion in the peritoneal space of the abdominopelvic cavity.
What is another name for cutaneous membrane?
Integument or skin.
Where are synovial membranes found?
Lining the cavities of joints.
What causes the clinical signs of heat, swelling, redness, and tenderness during inflammation?
Increased blood flow, plasma fluid accumulation, and irritation of nerve endings.
What is granulation tissue?
A bright pink tissue formed during healing, composed of collagen fibers and small capillaries.
Describe first intention wound repair.
Occurs with wounds whose edges are held in close apposition, leading to primary union without significant scarring.
Describe second intention wound repair.
Occurs when edges of the wound are separated, allowing granulation tissue to form and resulting in scar formation.
What is the role of goblet cells in mucous membranes?
They produce and secrete mucus, which lubricates and protects the lining of organs.
How do mucous membranes assist in the body’s defenses?
Mucus traps invading pathogens and foreign particles, particularly in the nasal passages.
