carbohydrates 1

Question 1

general functions

Answer 1

1- energy storage
2-structure and protection
3-cell-cell communication
4-oxidizable-form of energy

Question 2

maltose

Answer 2

main source is from breakdown of starch
has a free anomeric carbon- reducing sugar
used as a sweetener in baby food

Question 3

lactose

Answer 3

galactose +. glucose

has anomeric carbon

Question 4

sucrose

Answer 4

25% of carb diet

does not have an anomeric carbon so not a reducing sugar.

Question 5

anomeric carbon

Answer 5

1st carbon on monomer.
stabilises the monomer.
acts as reducing end if free-reducing sugar.
2 anomers are usually mirror images.

Question 6

polysaccarides. how are they defined?

Answer 6

they are defined by monomers, linkage, branching, length.

homopolysaccharides: made up of a single-repeating monomer unit
heteropolysaccharides: made up of 2 or more repeating monomers.

Question 7

starch

Answer 7

from plants.
made up from 2 forms of glucose: amylose(20-25% of starch) and amylopectin ( branched sub-units every 24-30 residues)(70/75% of starch)
many non reducing ends
alpha-helix structure.

Question 8

glycogen
where does it act
structure

Answer 8

in animal cells.
glucose branched every 8-12 amino acid residues.
acts in liver- blood glucose levels drop
acts in skeletal muscle-helps muscle contraction

Question 9

why are glycogen and starch good for storage?

Answer 9

1-compact
2-non-reducing ends which means they can be broken down easily
3- in hydrated-gel form-osmotically inactive

Question 10

glycoproteins. different types?

Answer 10

GAGs- glycosaminoglycans. role in mucus and synovial fluid around muscles and tissues. made up of repeating units of hexuronic acid and amino sugars
glycoproteins- higher protein than carb. found in ECM and CM but also in blood.
proteoglycan-higher carb than protein. formed by covalently binding GAG and protein. found on CM and between cells in ECM.

Question 11

Mucopolysaccharidoses

Answer 11

dysfunctions related to the build up of GAGs. happens when the enzymes which break downs GAGs don’t work.
e.g. Hurler syndrome–> thickens the arterial wall. leads to degradation of cornea and eventually dementia due to build upon cerebrospinal fluid.

Question 12

How can carbohydrates alter the function of proteins?

Answer 12

• affect its solubility
• affects its folding
• affects degradation
• affects communication