Connective Tissue Lab Flashcards
is characterized by an abundance of extracellular material and a relative paucity of cells
Connective tissue
all connective tissues in the body are derived from ______
mesoderm
connective tissues in the head are derived from _______
ectoderm
special types of connective tissue includes the following:
cartilage, bone, blood, hemopoietic tissue
a connective tissue that is found all over the body and can be regarded as primarily the “glue” that binds body parts together while allowing for some degree of movement
connective tissue proper
True or False: In connective tissue the cells are not bound to each other and are scattered individually in the extracellular substance.
True
The _________ of connective tissue is an amorphous, homogenous, transparent, and hydrated gel.
Ground substance
The ground substance consists mainly of water that is stabilized by
proteoglycans, hyaluronic acid, mineral salts, and glycoproteins
are the main structural constituents and are responsible for the gelatinous character of ground substance of connective tissue
proteoglycans
They are macromolecules that consist of a “core protein” to which disaccharides – in the form of glycosaminoglycans (GAGs) are attached covalently in a radiating pattern.
proteoglycans
is it the most abundant GAG in the ground substance of connective tissue
hyaluronic acid
it serves as the backbone to which proteoglycan molecules are attached by “link-proteins” to form proteoglycan complexes
hyaluronic acid
a non-sulfated molecule that has a diameter of 10 to 12 nm
fibrillin
glycoproteins in the ground substance of connective tissue, which are probably involved in cell adhesion and migration are:
fibronectin, laminin, and thrombospondin
three types of fibers in connective tissue
collagen, elastic, reticular
fibers that are present in all connective tissues in differing amounts
collagen fibers
they impart a white color to fresh tissue
collagen fibers
To better demonstrate collagen fibers under light microscope, special stains such as ______________ that color collagen fibers blue
Masson’s trichrome
most abundant protein in the body and accounts for about 25% of the body’s dry weight
collagen
collagen fibers are made of what protein
collagen
there are currently ___ known distinct types of collagen
28
only collagen types __, ___, & ___ make up practically all the collagen in connective tissue
types 1, 2, 3
collagen fibers are made up of what type of collagen
collagen type 1
a fibers that have a tensile strength that is greater than steel and are slightly flexible but inelastic
collagen fibers
the molecular precursor of a collagen fiber is
procollagen
consists of a polypeptide chain that is longer than those in mature collagen
procollagen
precursors of collagen that they synthesize
fibroblasts and mesenchymal cells
in the matrix of cartilage and bone, procollagen is synthesized by cells called
chondroblast and osteoblast
collagen fibers form _______ molecules by twisting around each other, much like the fibers of a rope, getting bound together by hydrogen bonds
tropocollagen
once tropocollagen molecules are formed it aggregates to form _______
microfibrils
these are fibrillar elements that are about 45 to 100 nm in diameter each
microfibrils
microfibrils group together to form bigger fibrillar structures called
fibrils (macrofibrils)
these are fine fibers that average 1.0 micromillimeter in diameter which usually do not ramify, rather branch and anastomose
Elastic fibers
True or False: when abundant, elastic fibers impart a yellow color to fresh tissue.
True
In H&E preparations, elastic fibers remain unstained and usually appear as ______________ that are difficult to distinguish with certainty from collagen fibers,
refractile pinkish-yellow lines
Elastic fiber when stained with orcein appear
blue to black
is a highly insoluble protein that is responsible for the elasticity of elastic fibers
Elastin
it is resistant to boiling and hydrolysis by acids, alkali, and most enzymes, but it can be hydrolyzed by the pancreatic enzyme elastase
Elastin
Elastin has how many genetic types
1 genetic type
Elastin in the body occurs in either two ways:
elastic fibers / elastic sheets or lamellae
these cells have the capacity to secrete the substances that are needed in the formation of elastic fibers are the
fibroblasts, and mesenchymal cells
elastic fiber formation
elastogenesis