Carbohydrates II Flashcards
What are glycosaminoglycans?
A range of polymers composed of repeating disaccharide units
How many units does a typical glycosaminoglycan contain?
100s
What is the major component of ground substance?
glycosaminoglycans
What is ground substance?
The “gunk” that holds tissues together
What is the synovial fluid?
The collection of fluid confined within a joint space
What is synovial fluid primarily made up of?
Ground substance
What can adjacent cells use ground fluid for?
Communication with one another
What is a hyaluronic acid an example of?
A glycosaminoglycan in ground substance
Where is hyaluronic acid found?
Vitreous humor of the eye
What is hyaluronic acid a disaccharide of?
D-glucuronic acid and N-acetyl-D-glucosamine
How are D-glucuronic acid and N-acetyl-D-glucosamine monomers linked in hyaluronic acid?
Beta (1–>3) linkages
How are hyaluronic acid disaccharides linked to each other?
beta (1–>4) linkages
How many disaccharide units does hyaluronic acid have?
250-250,000
What kind of structure does hyaluronic acid form?
A rigid, highly hydrated one
What are some characteristics of a hyaluronic acid solution?
Viscous, shock absorbant, shearing forces
What is added to the majority of proteins?
Carbohydrates
What is formed when a CHO is added to a protein?
A glycoprotein
What determines the nature of a carbohydrate?
The availability of certain enzymes
What is microheterogeneity?
Variation in the chemical nature of a substance that does not produce a major change in its properties
What is the range of carbohydrate content that can make up the glycoprotein?
1%–>99%
What are the two ways that a CHO can be linked to a protein?
N-linked and O-linked
How is the CHO attached to the protein in N-linkage?
It is beta linked to the aminde nitrogen of asparagine in the protein sequence
For a CHO to be added to an asparagine, how must the AA arrangement be after the asparagine?
Asn-AnyAminoAcid-Serine
Asn-AnyAminoAcid-Threonine
