Connective Tissue Flashcards
Are there many or few cells in connective tissue compared to epithelial tissue?
Very few cells compared to epithelial tissue.
Connective tissue has abundant matrix. True or Fasle?
True
What are the functions of connective tissue?
Physical support of other tissues.
Binds other tissues together.
Provides structural framework and opposes gravity.
Creates body contours.
Houses specialized tissues (hematopoietic and lymphatic).
Name and describe the embryonic connective tissue.
Wharton’s Jelly
Found in the umbilical cord
Contains some collagen and elastic fibers but mostly extracellular matrix.
Describe loose/areolar (adult) connective tissue.
Lots of fibroblasts compared to fibrous components.
Made up of type 1 collagen and elastic fibers.
Usually found beneath epithelial tissues of most organs including the Tunis adventitia of blood vessels.
Contains fibroblasts, mast cells, macrophages, and capillaries.
Describe sense regular (adult) connective tissue.
Dense is mostly made up of collagen.
Lots of fibrous components compared to fibroblasts.
Thicker bundles of collagen than loose CT.
Highly ordered bundles of collagen separated by single rows of fibroblasts.
Found in tendons and ligaments.
Describe irregular (adult) connective tissue.
Same as dense, but has no specific orientation of collagen bundles (looks swirly)
Found is fascia, submucosa of GI tract and dermis.
Describe reticular (adult) connective tissue.
A type of irregular tissue that has dominant reticular fibers associated primarily with lymphatic tissue.
Describe elastic (adult) tissue.
A type of dense irregular tissue that has an abundance of elastic fibers that form discontinuous lamellae.
Associated with the walls of blood vessels.
(*elastic tissue here is made by smooth muscle not fibroblasts).
How are adipocytes formed? Compare their size to cells and name the two types.
From undifferentiated mesenchymal cells in embryogenesis. They’re huge compared to cells. White and brown fat.
What is white fat?
Unilocular= single droplet of oil.
What is brown fat?
Multiocular- numerous smaller oil droplets.
More cytoplasm.
A lot of mitochondria (that’s why it’s brown)
Why do brown fat cells have so much mitochondria?
Infants can’t shiver, ATP is converted to heat.
Describe adipogenisis
Starts with Mesenchymal cell which can differentiate into a fibroblast, white fat or brown fat.
What is the connective tissue matrix made of?
Protein fibers and ground substances. It’s made by fibroblasts maintained by fibrocytes.
What are the protein fibers and ground substances that make up the matrix?
Protein fibers- collagen and reticular elastic fibers.
Ground substances - glycosaminoglycans and glycoproteins.
Name and give the purpose of 4 collagen types.
- General connective tissue and bone - tensile strength
- Hyaline and elastic cartilage- tensile strength
- Parenchyma organs and walls of BV-reticular framework
- Basement membranes- meshwork and scaffolding.
Explain type 1 collagen synthesis
- ER cleaves pre-sequence become procollagen
- Procollagen is secreted by fibroblasts into extracellular matrix (in inactive form with non helical ends to prevent polymerization).
- Peptidases cleave the non-helical ends to allow polymerization = tropocollagen.
- Collagen is formed.
What is a characteristic of tropocollagen assembly?
64 nm banded pattern.
What is Ehlers-Danlos Syndrome and what are some effects?
Defects involving collagen synthesis.
Effects: no tensile strength, loose skin, hyper mobile joints, and internal organ tissue ruptures or detaches.
Where is the connective tissue found?
Every other system except the CNS
