Connective Tissue Flashcards
What are the functions of connective tissue?
- Protection
- Storage
- Repair
- Transport
- Supports organs
Where is connective tissue derived from?
The mesoderm
What are the two main types of connective tissue?
Collagen and elastic
What 3 components make up connective tissue?
Fibres, cells and matrix
What is the appearance of collagen?
- White
- Thick
- Generally unbranched
What is the appearance of elastic tissue?
- Yellow
- Thin
- Branched
What cell produces collagen fibres? How do they do this?
Fibroblasts
pro-collagen —> tropocollagen —> collagen
What is an example of a dense and regular collagen connective tissue?
Tendons
What is an example of a dense and irregular collagen connective tissue?
Dermis (skin)
What is the structure of collagen?
- 3 chains of alpha helices coiled around each other
- Rich in glycine and proline
Which amino acids is collagen rich in?
Glycine and proline
What is required for the formation of collagen?
Vitamin C
How many genes are typically involved in the formation of collagen?
34
What type of collagen is the major component of bone, tendons and skin? What is the arrangement of these fibres like?
Type I
Long, branched fibres
What type of collagen is the major component of basement membranes? What is the arrangement of these fibres like?
Type IV
Sheet-like fibres
What type of collagen is the major component of anchoring fibrils in the basement membrane? What is the arrangement of these fibres like?
Type VII
Short fibrils
What cells produce elastic fibres?
Fibroblasts
Which protein do elastic fibres contain? Is it hydrophilic or hydrophobic?
Elastin - hydrophobic
What protein is elastin often bound with?
Fibrillin
Example of where elastic cartilage is found and its function
Epiglottis - flap made of elastic cartilage covered with a mucous membrane, attached to the entrance of the larynx. Protects airways
What can be used to stain elastic fibres?
Weigert’s stain
Are fibroblasts active? What is the appearance of their nucleus? What is the contents of their cytoplasm? Where is an example they are found?
- Yes
- Large, round, euchroamtic nucleus
- Lots of rough endoplasmic reticulum
- Umbilical cord
Are fibrocytes active? What is the appearance of their nucleus? What is the contents of their cytoplasm? Where is an example they are found?
- No
- Small, flat, heterochromatic nucleus
- Little rough endoplasmic reticulum
- Tendons
What are adipocytes?
Fat cells. They make up fat tissue
What are the two types of fat? Which is more common?
- White fat - more common
- Brown fat
Which types of fat generates heat?
Brown fat
Which type of fat is active?
White fat
What organelle do adipocytes have in large proportions? Why is this?
- Smooth endoplasmic reticulum - To produce lipids that fill the cytoplasm
What cells produce the matrix of connective tissue? What is the main component of this matrix?
- Fibroblasts
- Glycosaminoglycans (GAGs)
What main structural feature of GAGs allows them to support connective tissue?
They are highly negatively charged
- Causes attraction of Sodium (and other +ve ions)
- Draws water in to make matrix turgid and gel-like
What association do GAGs have with protein?
Can form proteoglycans by binding with them
Why is hyaluronic acid unique among GAGs?
Doesn’t contain any sulphate
Examples of GAGs
- Hyaluronic acid
- Heparan sulphate
- Keratan sulphate
- Chondroitin sulphate
Where can hyaluronic acid be found?
Cartilage, synovial fluid
Where can heparan sulphate be found?
Lung, basement membrane, liver
Where can keratin sulphate be found?
Cartilage, intervertebral discs
Where can chondroitin sulphate be found?
Bone, blood
