Connective Tissue Proper
Two subclasses: Loose & Dense
------Loose connective tissue:
-Areolar -Adipose -reticular
------Dense connective tissue:
---Dense regular
---Dense irregular
---Elastic (cartilage)

Connective Tissue: Blood
---Atypical connective tissue in that it doesn’t connect things/no mechanical supportt
---Classified as connective tissue because it develops from mesenchyme and is surrounded by matrix (plasma)
---Red and white cells in a fluid matrix (plasma)
--- Contained within blood vessels
---Functions in the transport of respiratory gases, nutrients, and wastes

Connective Tissue: Elastic (cartilage)
--Intermediate qualities to both dense connective tissue and bone
-- Stands up to tension and compression
--Tough and flexible
-- Lacks nerve fibers and is avascular
--Receives nutrients by diffusion from blood vessels located in the perichondrium (connective tissue membrane) surrounding it.
--Contains a lot of glycosaminoglycans (GAGs)
----- Cartilage matrix contains a lot of fluid (80% H2O)
----- H2O associated with springyness and nourishment delivery
-----Chrondroblasts are the major cell type in growing cartilage. They produce new matrix until the skeleton stops growing
--Three types of cartilage:
---Hyaline. --- Elastic. ---Fibrocartilage

Connective Tissue: Bone (Osseous Tissue)
---Hard, calcified matrix with collagen fibers found in bone
---Osteoblasts produce the organic component of the matrix
---Bone salts are placed on and between the fibers
--- Osteocytes are found in lacunae and are well vascularized
--- Bone is composed of units called osteons:
----Formed of concentric rings of bony matrix (lamellae) surrounding central canals containing blood vessels and nerve fibers
---Supports, protects, and provides levers for muscular action
---Stores calcium, minerals, and fat
---Marrow inside bones is the site of hematopoiesis