chapter 7 pt 2 Flashcards
type of polysaccharides that differ from each other in the relativity of their recurring monosaccharides units, in the length of their chains, in the types bonds limiting the units & in the degree of branching
Glycons
contain only a singular monomer species
homopolysaccharides
contains two or more different kinds (repeating disaccharides) (can have a linear or branched linkages based on enzyme specificity)
Heteropolysaccharides
structure arise from linkage type between ____ (structure support functions)
monomers
connections can occur from: 1 > ?, 1 > ?, 1-? (for alpha or beta)
2, 4, 6
some homopolysaccharides are storage forms of _____
fuel
most important storage polysaccharide are _____ in plant cells and _____ in animal cells and _____ (plant structural polymer)
starch; glycogen; cellulose
some homopolysaccharides serve _____ roles
structural
a water insoluble substance found in the cell wall of plants
cellulose
a linear homopolysaccharides composed of N-acetylglucosamine residues M(B1-4) linkage
chitin
steric factors & hydrogen bonding influence ______ folding
homopolysaccharide
a mixture of sulfated heteropolysaccharides make up of D-galactose and an L-galactose derivative either linked between C-3 and C-6
Agar
the agar component with the fewest charged groups
Agarose
- ______ are long, unbranched heteroglycans of repeating disaccharides linked to protein Ser or the residue
- heteropolysaccharides of the extracellular matrix
-highly viscous texture (slimy, mucous-like, elastic) due to hydration
Glycosaminoglycans
gel-like material that fills the extracellular space in the tissues of the multicellular animals (also called the ground substance)
Extracellular Matrix (ECM)
-specialized ECM heteropolysaccharides such as ______ are a family of linear polymers composed of repeating disaccharide units
glycosaminoglycans
What are glycosaminoglycans composed of?
composed of glucuronate, amino, and modified sugars (COO- and SO4-)
______ are polysaccharides and peptides
Glycoconjugates
what is the function of glycosaminoglycans?
ex: Heparin segment
extracellular matrix mesh with fibrous proteins (collagen) in connective tissues, synovial fluid, eye vitreous humor
function of Heparin segment
binds to some cells to regulate blood vessel formation and reduces viral/ bacterial virulence
contains alternating residues of D-glucuronic acid & N-acetylglucosamine
Glycosaminoglycan hyaluronan (hyaluronic acid)
component of the ECM of cartilage & tendons to which it contributes tensile strength & elasticity as a result of its strong noncovalent interactions with other components of the matrix
Hyaluronan
contributes to the tensile strength of cartilage, tendons, ligaments, heart valves, and the walls of the aorta
Chondroitin sulfate
contributes to the pliability of skin and also present in blood vessels and heart valves
Dermatan sulfate
has no uronic acid and their sulfate content is variable
Keratan sulfate
produced by all animal cells and contains variable arrangements of sulfated and non sulfated sugars
Heparan sulfate
polysaccharides & _______ are information carriers carbohydrates
oligosaccharides
informational carbohydrate is covalently joined to a protein or a lipid to form a _____
glycoconjugate (biologically active molecule)
-macromolecules of the cell surface or ECM
-major components of all extracellular matrixes
Proteoglycans
have one or more oligosaccharides of varying complexity joined covalently to a protein
Glycoproteins
What are glycosphingolipids?
plasma membrane components in which the hydrophilic head groups are oligosaccharides
neurons are rich in glycosphingolipids which help in _____ conduction and ______ formation
nerve; myelin
2 major families of proteoglycans that contain heparan sulfate chains:
syndecans & glypicans
have a single transmembrane domain & an extracellular domain bearing 3 to 5 chains of Heparan sulfate & some cases chondroitin sulfate
syndecans
attached to the membrane by a lipid anchor a derivative of the membrane lipid phosphatidylinositol
glypicans
some proteoglycans can form _____ _________
proteoglycan aggregates
what are proteoglycan aggregates?
enormous supramolecular assemblies of many core proteins all bound to a single molecule of hyaluronan
glycoproteins have ______ attached oligosaccharides
covalently
Glycolipids and ____ are membrane components
lipopolysaccharides
