Monosaccharides

carbohydrates

hydrates of carbon

general emprical formula of carbohydrates is

(CH_2O)m

carbohydrates are

saccharides, sugars, glucans

carbohydrates are made by all organisms but most are made by

photosynthetic organisms

Carbohydrates are the most

abudant biochemical molecule on earth by weight

How are carbons classified

by the number of monomers (sugars) joined together

monosaccraride

single unit

oligosaccharide

2 units

polysaccharide

less than 20 units

glycans

another word for polysacrides

Homoglycans

polysaccharides assembled from all the same sugar.

Heteroglycans

polysaccharides assembled from different sugars.

Carbohydrates serve as

energy and fuel for cells

What are the key functions of carbohydrates

1. energy

2. energy storage

3. structure

4. metbaolic intermediates

5. backbond structure

6. modification groups

7. identifiers for cells

Oligosaccharides act as

identifiers for cells

The sugar code is

how cells use specific oligosaccharides to encode important information about intraceulluar targeting of proteins, cell-cell interactions, cell diferentaion, tissue development, and extracellular signals

aldoses

aldehyde containing

ketoses

ketone containing

chirality is led by

D or L

D =

dexta, chiralitu most widelyused in carbohydrates

L =

levo, chirality are not made or used much

L and D glucose are

enantiomers

D-glucose chirality is

D,L,D,D

DIASTEREOMERS

stereoisomers that are not mirror images

Epimers

stereoisomers that differ in configuration at only one carbon

D-galactose

D-mannose

D-ribose

D-glyceraldehyde

d-ethythose

D-ketoses are arranged according to the

number of c atoms and all possible steroisomer configurtions

dihydroxyacetone

D-ribulose

D-xylulose

D-fructose

Hemiacetal

C attached to: 2 O’s, one of which is an OH 1H 1 R-group

C attached to: 2 O’s, one of which is an OH 2 R-group in

hemiketal

D-OH point

DOWN

L-oh points

up

pyranoses

two glucose compounds with 5c atoms and 1 O atom

anomeric carbon is the

most reactive carbon

Anomeric carbon

the c1 atom bonded to 2 os

b-d-ribofuranose is an

important furnose in nucliec acids

pyranose and furnose rings are

strained and there are different bent conformation to relive the strain

axial

vertical

equitorial

away from the ring