gag Flashcards
What are glycosaminoglycans (GAGs)?
Long unbranched polysaccharides consisting of repeating disaccharide units.
Example: Chondroitin sulfate
What is the primary function of GAGs?
They help in maintaining the structural integrity of tissues by attracting water and forming a gel-like matrix.
Example: Hyaluronic acid
Name the repeating disaccharide units in GAGs.
An amino sugar (like N-acetylglucosamine) and a uronic sugar (like glucuronic acid).
Example: Keratan sulfate
How do GAGs contribute to tissue hydration?
GAGs are highly negatively charged, attracting water molecules and creating a hydrated gel-like matrix.
List four main types of glycosaminoglycans.
Hyaluronic acid, chondroitin sulfate, heparan sulfate, and keratan sulfate.
Which GAG is most abundant in cartilage?
Chondroitin sulfate.
What is the role of hyaluronic acid in the body?
It acts as a lubricant in joints and helps maintain the shape of the eyeball.
How is heparin related to GAGs?
Heparin is a type of GAG that functions as an anticoagulant.
What is a unique feature of keratan sulfate?
It is a sulfated GAG that does not contain a uronic acid.
Where is dermatan sulfate primarily found?
In skin, blood vessels, and heart valves.
Which GAG is not typically covalently attached to proteins?
Hyaluronic acid.
How do GAGs influence cell signaling?
They bind to growth factors, enhancing or inhibiting their signaling pathways.
What enzyme is responsible for degrading GAGs?
Lysosomal hydrolases.
Which GAG is most closely associated with corneal transparency?
Keratan sulfate.
What condition is associated with defective degradation of GAGs?
Mucopolysaccharidoses (MPS), a group of metabolic disorders.
Which GAG plays a crucial role in the basement membrane?
Heparan sulfate.
How does chondroitin sulfate contribute to joint function?
By providing resistance to compression in cartilage.
What structural feature makes GAGs highly viscous?
Their long, unbranched chains and high degree of hydration.
Which GAG is used therapeutically to treat osteoarthritis?
Hyaluronic acid.
What is the difference between heparin and heparan sulfate?
Heparin has a higher degree of sulfation and is more effective as an anticoagulant.
