Lecture 3: Connective Tissue Flashcards
Describe the function of connective tissue in the body
Connective tissue binds, supports, and strengthens other body tissues, serves as a major transport system (e.g., blood), and acts as a site for stored energy reserves (e.g., adipose tissue).
Explain the vascularity of connective tissue.
Connective tissue can be highly vascular, meaning it has a rich blood supply.
Except for cartilage, which is avascular.
And Tendons, which have very little blood supply.
Define the components of connective tissue.
Connective tissue is made of extracellular matrix (ECM) and cells.
How does the structure of the extracellular matrix (ECM) influence connective tissue properties?
The structure of the ECM largely dictates the qualities of connective tissue, such as the firmness of cartilage and the hardness of bone.
What is the composition of the extracellular matrix (ECM)?
The ECM is composed of ground substance and protein fibers.
Describe the components of ground substance in the extracellular matrix.
Ground substance is made of water, proteins, and polysaccharides.
Explain the role of glycosaminoglycans (GAGS) in connective tissue.
Glycosaminoglycans (GAGS), also known as mucopolysaccharides, are long unbranched polysaccharides that attract water, contributing to the jelly-like consistency of ground substance.
What are proteoglycans and how are they formed?
Proteoglycans are formed by the combination of core proteins and glycosaminoglycans (GAGS).
Describe the function of sulphated glycosaminoglycans in connective tissue.
Sulphated GAGs bind covalently with core proteins to form proteoglycans and help them bind with water.
What is the role of hyaluronic acid in connective tissue?
Hyaluronic acid is a viscous, slippery substance that lubricates joints and helps maintain the shape of the eyeball.
Explain the function of hyaluronidase.
Hyaluronidase is an enzyme produced by white blood cells, sperm, and some bacteria that dissolves hyaluronic acid, allowing easier movement through tissues.
What is aggrecan and how is it formed?
Aggrecan is a proteoglycan made of chondroitin sulfate and keratin sulfates, which becomes an aggregate when combined with hyaluronic acid.
Describe the differences between sulphated and non-sulphated glycosaminoglycans.
Sulphated GAGs bind with core proteins to form proteoglycans, while non-sulphated GAGs, like hyaluronic acid, do not bond directly with core proteins but to various Proteo-glycans
How do glycosaminoglycans contribute to the properties of ground substance?
Glycosaminoglycans are highly polar and attract water, which helps to create the jelly-like consistency of ground substance.
What is the repeating disaccharide unit in glycosaminoglycans?
The repeating disaccharide unit consists of an amino sugar (e.g., N-acetylglucosamine) and a uronic sugar (e.g., glucuronic acid).
What are proteoglycans composed of?
Proteoglycans are composed of a core protein and glycosaminoglycans (GAGs).
What is the role of sulphated GAGS?
Sulphated GAGS bind covalently with core proteins to form proteoglycans and help them bind with water.
Where is dermatan sulphate found?
Dermatan sulphate is found in skin, tendons, blood vessels, and heart valves.
What is heparin sulphate and where is it found?
Heparin sulphate is a type of sulphated GAG found in various tissues, including blood vessels.
What is keratin sulphate and where is it found?
Keratin sulphate is found in bone, cartilage, and the cornea of the eye.
What is the function of chondroitin sulphate?
Chondroitin sulphate supports and provides adhesive features of cartilage, bone, skin, and blood vessels.
What is exophthalmos and its association with thyroid disease?
Exophthalmos is an abnormal condition associated with autoimmune over-activation of the thyroid, leading to increased orbital contents due to the deposition of glycosaminoglycans and influx of water.
Who is most commonly affected by exophthalmos?
Exophthalmos is most common in younger women.
What are the characteristics of collagen fibres?
Collagen fibres are very strong and flexible, forming in parallel bundles to resist pulling forces. They vary in features based on different tissues.