CONNECTIVE TISSUE

Connective
Tissue
Proper

Fluid/liquid
Connective
Tissue

Supporting
Connective
Tissue

Loose
Connective
Tissue

Dense
Connective
Tissue

Adipose
CT

Reticular
CT

Areolar
CT

Dense
irregular
CT

Elastic
CT

Dense
regular
CT

Blood

Lymph

Bone
(Osseous)
Tissue

Cartilage

Functions

provides elasticity # #

transport system # #

protects and insulates internal organs # # #

stores energy # #

supports and strengthens other tissues # # # # # # #

immune response # #

binds structures together # # #

Structure

  • abundant and widely distributed
  • two basic elements: extracellular matrix and specialised cells (immature cells (-blast) and mature cells (-cyte))
  • cells rarely touch
  • extracellular matrix secreted by cells
  • consistency varies
  • good nerve and blood supply (except cartilage and tendons)

Specialised
cells

Adipocytes

Leukocytes
(WBC)

Fibroblasts #

  • secrete protein fibres (form chains outside cell) and matrix
  • fat cells - store energy in form of fat

Macrophages - develop from monocytes and engulf bacteria and debris by phagocytosis

Plasma cells - develop from B lymphocytes and produce antibodies that fight against foreign substances

Mast cells - produce histamine that dilate small blood vessels

Extracellular
matrix

Ground
substance

Fibres

Collagen fibres
S - composed of collagen protein
F - tough and resistant to stretching. Allow some flexibility
L - bone, cartilage, tendons, ligaments

Elastic fibres
S - composed of elastin protein surrounded by fibrillin glycoprotein
F - provide strength and stretching capacity
L - skin, blood vessels lungs

  • proteins secreted by fibroblast cells

Reticular fibres
S - composed of collagen protein and a specific glycoprotein
F - support wall of blood vessels, spleen, lymph nodes, nerve fibres, supporting network around fat cells, skeletal and smooth muscle fibres

loosely woven fibres throughout tissues

Cells - fibroblasts, plasma, macrophages, mast cells, WBC

Fibres - collagen, elastic, reticular

Ground substance - gelatinous ground substance

more numerous, thicker and dense fibres
considerably fewer cells than loose connective tissue

L - subcutaneous layer of integument

F - support and strength

  • proteoglycans (proteins carrying large unbranched highly charged polysaccharide side chains) and glycoproteins
  • fluid, gelatinous or solid
  • makes sure nutrients are exchanged between cells and outside
  • equivalent of cytosol outside cells

Cells - fibroblasts, adipocytes, macrophages, mast cells

Fibres - collagen, elastic, reticular

Ground substance - tissue fluid

L - wherever areolar CT is located - inseparable

F - support, reduce heat loss, energy reserve, protection, brown fat in newborns

Cells - fibroblasts (reticular)

Fibres - reticular. Form fine delicate network

L - stroma of organs, bind together cells of smooth muscle

F - bind cells together

Cells - fibroblasts

Fibres - collagen in parallel bundles with fibroblasts between

L - tendons (connect muscle to bone), ligaments (bind bone to bone)

F - support and strength, binds together

Cells - fibroblasts (scattered sparsely)

Fibres - collagen irregularly arranged

L - found where tension exerted in any direction

  • heart valves, perichondrium, tissue surrounding cartilage, periosteum, white of eyeball

F - strength

Cells - fibroblasts

Fibres - elastic (branching). Can stretch and return to original shape

L - lung tissue, vocal cords, ligament between vertebrae, aorta

S - elasticity

extracellular matrix containing mineral salts and collagenous fibres and osteocyte cells

Spongy bone

  • sponge-like with spaces and trabeculae (struts of bond surrounded by red bone marrow)

Compact bone

  • solid, dense bone

F - protects, provide for movement, stores minerals, site of blood cell formation

S

  • dense network of collagen and elastic fibres embedded in chondroitin sulfage
  • strength from collagen fibres
  • resilience due to chondroitin sulfate
  • chondrocytes occur with spaces called lacunae in the extracellular matrix. Secrete ground substance extracellular matrix components
  • surrounded by dense irregular tissue membrane - perichondrium #
  • avascular (except in perichondrium)



Hyaline
cartilage

S

  • fine collagen fibres embedded in gel-type matrix
  • avascular and no nerves = slow repair

F

  • flexibility and support at joints, reduces friction and absorbs shock

L

  • most abundant (ends of bones), weakest
  • joints, respiratory tract
  • immature skeleton

Fibrocartilage

S

  • bundles of collagen fibres in ground substance
  • lacks perichondrium (no protective irregular connective tissue)

F

  • support, strength, binding together

L

  • strongest of the 3 types
  • interverterbral discs, patella

Elastic
cartilage #

S

  • threadlike network of elastic fibres
  • chondrocytes secrete elastin and fibrillin
  • perichondrium present

F

  • strength, elasticity, maintain shape of organs (even after deformation)

L

  • ear, nose, vocal cartilages

S

  • liquid matrix - plasma
  • formed elements - RBC, leukocytes, platelets

F

  • supply of O2, immunity

S

  • extracellular fluid flowing in lymph vessels
  • similar composition to plasma (less protein)

F

  • immunity, movement of molecules