AP Unit 1- Chpt 4 Tissue
state the location, source, and function of the basement membrane
LOCATION: attaches to and supports the overlying epithelial tissue and anchors it to the underlying connective tissue. FUNCTION: it forms a surface along which epithelial cells migrate during wound healing and restricts passage of molecules between the epithelium and connective tissue.
General location and function of mucous membranes serous membranes.
Location- lines thoracic or abdominal cavities, and it covers the organs that are within the cavity. Consist of areolar connective tissue covered by mesothelium (simple squamous epithelium) Function- The mesothelium of a serous membrane secretes serous fluid, it allows organs to glide easily over one another or to slide against the walls of cavities.
Dense Regular Connective Tissue
Function- Provides strong attachment between various structures Location- Forms tendons (attach muscle to bone); most ligaments (attach bone to bone); aponeuroses (sheetlike tendons that attach muscle to muscle or muscle to bone) Description- Consists mainly of collagen fibers regularly arranged in parallel bundles with fibroblasts in rows between bundles.
Define tendon and ligament and state the connective tissue type of which they are composed.
Tendon-attach muscle to bone ligament- attach bone to bone DENSE REGULAR CONNECTIVE TISSUE
Define membrane
flat sheets of pliable tissue that cover or line a part of the body
Fibroblasts
football-shaped cells; produce fibers and ground substance
Describe the extracellular matrix
material located between its widely spaced cells. The ECM is secreted by connective tissue cells and accounts for many of the functional properties of the tissue.
State the functions of ground substance
supports cells, binds them together, stores water, and provides medium for exchange of substances between the blood and cells of the tissue.
Endothelium
the simple squamous epithelium lining blood vessels, the heart, and lymphatic vessels
Distinguish among the four basic types of body tissues
• Epithelial tissue covers body surfaces, lines hollow organs, body cavities, and ducts. Forms glands, allows body to interact with its internal and external environments. • Connective tissue protects and supports the body and its organs. Various types of tissue bind organs, store energy as fat, help provide immunity against disease-causing organisms. • Muscle tissue composed of cells that can contract to generate physical force needed to move body structures and generate heat • Nervous tissue detects changes in a variety of conditions inside/outside the body and responds by generating electrical signals called action potentials that activate muscle contractions and gland secretions
NEED TO KNOW
- fibroblast is main cell type of Connective Tissue Proper -osteocyte is main cell type of osseous tissue
Major functions of connective tissue (HCPD)
-Holds you together and upright -Contains noncellular matrix and cells -Protects vital organs -Derived from mesenchyme
Location and basic organization of connective tissue and epithelial tissue
-many cells are tightly packed together with little or no ECM, while in connective tissue a large amount of ECM material separates cells that are usually widely scattered. -epithelial tissues almost always form surface layers and are not covered by another tissue. An exception is the epithelial lining of blood vessels where blood constantly passes over the epithelium -epithelial tissue has no blood vessels, while most connective tissues have significant networks of blood vessels they are always found immediately adjacent to blood-vessel-rich connective tissues
Distinguish between "cyte" and "blast" cells of connective tissues.
Blast cells retain the capacity for cell division and secrete the ECM once the ECM is produced, the blast cells differentiate into mature cells (Cyte) Mature cells have reduced capacities for cell division and ECM formation and are mostly involved in maintaining the ECM
Dense Irregular Connective Tissue
Description- Collagen fibers; usually irregularly arranged with a few fibroblasts. Location- Fasciae tissues around muscles and other organs); dermis of skin; fibrous capsules of organs and joints; heart valves. Function- Provides tensile (pulling) strength in many directions.
Distinguish between the two general types of epithelium.
Epithelial tissue may be divided into two types. Covering and lining epithelium forms the outer covering of the skin and outer covering of some organs. It also lines body cavities and hollow organs. Glandular epithelium constitutes the secreting portion of glands such as the thyroid gland, adrenal glands, and sweat glands.
State the function of glands and distinguish between exocrine and endocrine glands.
Function: secretion exocrine-secrete their products into ducts that empty onto the surface of a covering and lining epithelium such as the skin surface or the lumen of a hollow organ. endocrine-enter the interstitial fluid and then diffuse directly into the bloodstream without flowing through a duct.
General location and function of mucous membranes
Location-lines a body cavity that opens directly to the exterior. Line the gastrointestinal tract, respiratory tract, reproductive tract, and much of the urinary tract. They consist of both a lining layer of epithelium and an underlying layer of connective tissue Function-body's defense mechanisms, prevents the cavities from drying out, traps particles in respiratory system and lubricates food to go down gastrointestinal tract
Elastic fibers
ability to stretch up to 150% of their relaxed length without breaking, they have elasticity
Collagen fibers
allows tissue flexibility and gives ability to resist stretching
Adipocytes
are connective tissue cells that store triglycerides (fats)
Goblet cells
are modified columnar epithelial cells that secrete mucus, a slightly sticky fluid, at their apical surfaces; before release, mucus accumulates in upper portion of cell, causing it to bulge and making the whole cell resemble a goblet or wine glass.
state the functions of cell junctions
prevent substances from passing between cells and leaking out of these organs.
Reticular fibers
provide support & strength, support in the walls of blood vessels and form a network around cells in some tissues such as areolar connective tissue, adipose tissue, and smooth muscle tissue.
Mesothelium
simple squamous epithelium of serous membranes