Bio-Chem questions, please help!?

Question

Disaccharides can differ from each other in all of the following ways except...

a) in the # of their monosaccharides

b) as enantiomers

c) in the monomers involved

d) in the location of their glycosidic linkage

e) in their structural formulae

Which of the following is not true of cellulose?

a) It is the most abundant organic compound on earth

b) it differs from starch b/c of the configuration of glucose and the geometry of the glycosidic linkage

c) it may be hydrogen bonded to neighboring cellulose molecules to form mocrofibrils

d) few organisms have enzymes that hydrolyze its glycosidic linkages

e) its monomers are glucose w/ nitrogen-containing appendages

a fatty acid w/ the formula C16H32O2 is...

a) saturated

b) unsaturated

c) branched

d) hydrophilic

e) part of steroid molecule

my bio teacher gave me a packet with a few questions [not graded] to help prepare for the exam on the first day of school and i need to make sure i finish this for good prep! thx.

Answer 1

You have 3 questions.

1.  The key is Di.  Meaning two.  If it's a disaccharide it has two saccharides.  Answer A.

2.  Cellulose uses a beta linkage which most animals can't break down.  Where Starch used alpha linkages.  So your answer is B.

3.  Since it's an acid it has to end in, -COOH.  Which leaves C15 and H31  The general formula for a saturated alkane is 2n + 2 so your answer has to be B.  It's an unsaturated compound.