Ch. 5 - Connective Tissue; Ch. 6 - Adipose Tissue; Ch. 7 - Cartilage; Ch. 8 - Bone; Ch. 12&13 - Blood & Hematopoiesis Flashcards
What is the major component of CT?
ECM
Extracellular matrix (ECM)
Combinations of protein fibers and ground substance
Ground substance
Complex of anionic, hydrophilic proteoglycans, glycosaminoglycans (GAGs), and multi adhesive proteins (laminin, fibronectin, and others)
Provides the medium for exchange of nutrients and metabolic wastes between cells and the blood; transports materials
Part of the matrix
Has a lot of water called solvation water because it is very hydrophilic
Connective tissue (CT)
Abundant tissue that connects/holds and protects tissues and organs of the body
Contribute to form and shape
CT can provide a means of _______ and _______.
movement; storage
Give an example of how CT can provide a means of movement.
Bones are attached to skeletal muscle
Give two examples of how CT can provide a means of storage.
Bones store calcium
Adipose stores triglycerides
What are the three important components when describing CT?
- Cells
- Ground substance
- Fibers
Matrix
Ground substance and fibers
Conduit by which materials go from blood to cell and cell to blood
What are the three components of ground substance?
Consists of structural glycoproteins, GAGs, and proteoglycans
Glycoproteins
Part of the ground substance
Insoluble anchoring proteins
Fibronectin, collagen, lamanin, and others
GAGs
Glucosaminoglycans
Part of the ground substance
Linear polysaccharide made up of units of repeating disaccharides
Hydrophilic –> absorb water
Proteoglycans
Part of the ground substance
Protein made up of a central core attached to many GAGs
Absorb water –> hydrophilic due to GAGs
What are the four classifications of CT?
- Embryonic CT
- CT proper
- Special CT
- Supporting CT
Embryonic CT
Forms early in development
Two kinds
1. Mesenchyme embryonic CT
2. Mucous CT
Mesenchyme embryonic CT
Develops into all CT cells
Also develops into endothelial, muscle, and blood
CT proper
Fibrous CT
Two kinds
1. Loose fibrous CT
2. Dense fibrous CT
Loose fibrous CT proper
Surrounds and supports organs and holds them in place
Made up of fibroblasts, matrix, and fibers
Lots of transient cells (i.e. RBC)
Dense fibrous CT proper
Two kinds
- Dense regular fibrous CT
- Dense irregular fibrous CT
Special CT
Special functions Three kinds 1. Adipose 2. Hematopoietic 3. Elastic tissue
Adipose
Special CT
Fat tissue (found subcutaneously)
Insulator (thermoregulation), shock absorber, stores triglycerides
Hematopoietic tissue
Special CT
Elastic tissue
Special CT
Supporting CT
Provides support
Two kinds
1. Bone
2. Cartilage
Bone
Supporting CT
Cartilage
Supporting CT
Fibroblasts
Cells of the CT proper derived from embryonic mesenchyme CT cells
Long, somewhat fusiform cells with stellate endings
Very active
Fixed cell population
Secrete fibers and ground substance
Can become fibrocytes
Do fibroblasts readily undergo mitosis?
No
Fibrocyte
Very flat, elongated cells
Not very active
Myofibroblast
Intermediate cells
Contract
Found in muscle
Used for tissue repair by pulling wounded ends of tissue together (wound healing)
CT proper also has a transient cell population at times, consisting of _______, _______, _______, _______, and undifferentiated _______.
leukocytes; macrophages; mast cells; plasma cells; lymphocytes
What are the fibers of CT proper?
Collagen, elastin, and reticular fibers
Collagen fibers
CT proper fiber
Protein (has 28 forms)
Synthesis starts in the cell and ends outside the cell
Collagen synthesis pathway
(Inside cell) pre-procollagen –> procollagen –> (procollagen peptidase) –> (Outside cell) tropocollagen –> collagen
Reticular fibers
CT proper fiber Form of collagen (collagen III) Found in the matrix Found in lymph nodes Very thin, can't see with H&E stain Can see with silver dye
Reticular fibers can be seen in paraffin sections using silver dye because they are _______.
argyrophilic
Argyrophilic
Affinity for silver salt
Reticular tissue
Reticular fibers and fibroblasts
Elastin synthesis pathway
Similar to the of collagen
Also needs a receptor
Also is finished outside the cell
(Inside cell) Pre-proelastin –> proelastin –> (outside cell) elastin
What three things is the ground substance of CT proper composed of?
- GAGs
- Proteoglycans
- Glycoproteins
Disaccharide units of GAGs are made up of _______ linked to a _______.
uronic acid; hexosamine
Hexosamine
6-C amino sugar
Uronic acid of GAG disaccharide units
Glucaronic acid
Iduronic acid
What is the least abundant component of loose fibrous CT proper? What is their organization?
Fibers
They are very loosely attached and organized
What is the most abundant component of dense fibrous CT proper?
Fibers
Dense regular fibrous CT
Has many fibers running parallel in the same direction
Densely arranged with rows of fibroblasts in between
Found in tendons and ligaments (attaches to muscle and bone)
Dense irregular fibrous CT
Fibers all running in different directions
No rows of fibroblasts, dispersed throughout instead
Found in dermis of the skin (can stretch and recoil skin)
Elastic tissue
Dense regular fibrous CT made up of elastin
Yellow elastic tissue
Elastic tissue that help to hold the vertebrae in place and suspend the penis
Adipose tissue is a _______ population of cells.
stable
Stable population of cells
Overall population number remains the same
Controlled genetically in adults, so sometimes the numbers change
What determines the number of adipocytes?
Postnatal dietary intake
Higher caloric intake results in a _______ number of adipocytes for life, postnatally.
higher
The _______ cell number stays the same throughout life, however their _______ can fluctuate.
number; size
Adipose cells originate from what cells?
Mesenchyme embryonic CT cells