connective tissue is most _____ and ______
abundant, variable tissue in the body
2 types of connective tissue
- embryonic
2. adult
2 types of embryonic connective tissue
- mesenchyme
2. Mucous
2 types of adult connective tissue
- connective tissue proper
2. specialized
5 types of connective tissue proper
- loose (areolar)
- reticular
- dense regular
- dense irregular
- Adipose
2 types of specialized connective tissue
- blood
- supporting connective tissue
cartilage
bone
function of connective tissue
BIPCIST Binds, support, strengthens insulation protection compartmentalization immune response storage of energy reserves transport
function: protection examples
bones- skull, vertebrae
function insulation example
adipose tissue
characteristics of connective tissue
- cells in extracellular matrix
- common origin
- degrees of vascularity
connective tissue common origin is from what
mesenchyme cells
cells in extracellular matrix
few cells, very spread out. Most is extracellular matrix
degrees of vascularity
bone is highly vascularized
cartilage is avascular
dense connective tissue is somewhat vascularized
components of connective tissue
cells and ECM
components of ECM
protein fibers
ground substances
3 protein fibers types
- collagen
- reticular
- elastic
what secretes protein fibers
cells in the ECM
ground substance
provides medium through which things can diffuse. can be fluid, gel like, or calcified, very hydrophilic
ground substances types
- Glycosaminoglycans GAG
- proteoglycans
- multiadhesive glycoproteins
Glycosamineglycans (GAG)
hyaluronic acid and chondroitin sulfate
multiadhesive glycoproteins
laminin and
fibronectin
structural cells in connective tissue
fibroblast, chrondroblast, osteoblast, odontoblast- production of fibers and ground substances
immunologic cells in connective tissue
plasma cells, lymphocytes, eosinophil
defense cells in connective tissue
mast cells, basophils, macrophages, neutrophils
energy reserve/heat production
adipose cells
fibroblast
produce fibers and ground substances most common type of cell in CT produce and maintain ECM large nucleus, cyto tapers out, spindle shape cells 2 levels of activity- quiesto, active
quiesto fibroblast cells
sit around, much smaller. fewer processes coming off from cell. smaller darker chromatin (heterochromatin) acidophilic, not a lot of translation
active fibroblast
abundant cytoplasmic processes, euchromatin ( not densely packed) cytoplasm full of rough ER. cyto more basophilic
mast cells
originate from bone marrow, migrating in down picture, large oval and rounded, small spherical shaped
strucutures - basophilic secretory granules, very small (inside)- contain certain substances, histamine -
have role in inflammatory, allergic, immune responses. Nice spherical central nucleus
plasma cells
Plasma cells- derived from B lymphocytes, responsible for synthesis
of antibodies. Very large. Basophilic cytoplasm, due to lots of Rough ER
spherical nucleus off to side.
three types of connective tissue fibers
collagen
reticular
elastic
collagen fibers
high tensil strength, very strong, very resiliant to pulling forces, but some flexibility. found in most type of connetice tissue
where are collagen fibers found
bones, cargilage, tendon, ligaments.
reticular fibers
collagen type 3 protein. very similar to collagen, but much thinner. form very extensive network, big branches because they do this they are used for support, framework. H and E stain doesnt stain them. Need silver stain to observe these fibers, stain black.
elastic fibers
smaller than collagen fibers. also often branch and network, made up of protein elastin, can stretch 150% of length, still strong. see alot of these fibers in blood vessels, skin, lungs,
procollagen fibers made up of what
3 alpha collagen chains
what are alpha collagen chains made up of
polypeptides
procollagin come together and form what
fibril
GAGs
largest of GAGs, and most common
all have (-) charge, bind water. diffusion
property.
Proteoglycans
protein core, that GAGs can attach to.
multiadhesive glycoproteins (laminin fibronectin)
globular proteins, which chains of monosaccarides can attach serve as glue that link different compoents of ground substance together. attach to ECM!
mesenchyme cells
long, undifferentianted mesenchyme cells, oval nucleus, fine chromatin if active, thin processes coming off, very viscous
ground substances. eosinphilic, thses might be more quiet than active.
mucous cells
present in umbillical cord, referred to as wharton’s jelly. Also very similar in form to what is found in pulp cavity in young
teeth. very gelanous like extracellular matrix. spindle shape cells, triangle nucleus, widely dispearced. few collagen fibers
this tissue not as prevalent
most widely distributed connective tissue in the body
loose (areolar) connective tissue
main cells in loose CT
fibroblast, macrophages
arrangement of fibers in loose CT
loosely organized, very far away, lots of space for ground substances
main characteristics of loose CT
all 3 types of fibers present in random arrangement cannot undergo lots of pressure/stress very flexible well vascularized body's universal packing material gel-like
function of loose CT
wraps and cushions organs
important role in inflammation
holds and conveys tissue fluids
location of loose CT
under epithelial (lamina) of mucous membrane packages of organs surrounds capillaries
only fiber we see in reticular CT
type 3 collagen, forms networks branches, with loose ground substance
function of reticular CT
forms soft skeleton, internal framework, support free cells, reticular cells lie on framework. binds together smooth muscle tissue cells
location of reticular CT
lymph nodes, bone marrow, spleen
stain to see reticular CT
silver stain, stains black
main fiber in dense regular CT
type 1 collagen
decription of dense regular CT
less flexible, more resilient to stresses and pressures, not many cells cuz so many fibers, poorly vascularized, wavy, run parallel in direction of pull
major cell types of dense regular CT
fibroblast
location of dense regular CT
tendons, ligaments, aponeurosis
function of dense regular CT
attaches muscle to bone, bone to bone
description of dense irregular CT
irregularly arranged collagen type 1 fibers, go in different directions, major cell type is fibroblast
function of dense irregular CT
able to withstand tension exerted by multiple directions, provides structural strength
location of dense irregular CT
dermis of the skin, submucosa of digestive tract
two types of adipose tissue
white adipose tissue
brown adipose tissue
white adipose tissue
main adipose tissue in adults, unilocular - one main fat cell, made of triglycerides, rim of cytoplasm, flatted nucleus off to side, very well vascularized
function of white adipose tissue
energy storage, insulation, cushioning of vital organs and secretion of hormones.
brown adipose tissue
spherical eccentric nucleus. multilocular, predominate type in newborns and fetus
function of brown adipose tissue
heat production