ch. 13 carbohydrates

ch 13, 14, 16, 18

the carbon cycle

6CO2 + 6H2O + energy ⇌ C6H12O6 + O6

carbohydrates broken down via _____ to gain energy

respiration

carbohydrates made by plants via ____

photosynthesis

aldehyde on the first carbon indicates what type of carbohydrate

aldose

ketone on the second carbon indicates what type of carbohydrate

ketose

what type of carbohydrate does this fischer projection display

aldose

what type of carbohydrate does this fischer projection indicate

ketose

a carbohydrate with a three carbon chain

triose

a carbohydrate with a four carbon chain

tetrose

a carbohydrate with a five carbon chain

pentose

a carbohydrate with a six carbon chain

hexose

a carbohydrate with a seven carbon chain

heptose

what is a monosaccharide

the smallest form of a carbohydrate molecule

what is a disaccharide

2 monosaccharides bonded together

what type of bond allows for monosaccharides to bond to each other

a glycosidic bond

how is a glycosidic bond formed?

when a carbon from the first carbonyl group of the first monosaccharide bonds with the hydroxyl group on the fourth carbon of the second monosaccharide

what type of reaction occurs when a glycosidic bond is formed

dehydration reaction

what is a polysaccharide

more than 2 monosaccharides bonded together

what are chiral molecules

molecules that cannot be superimposed on its mirror image ex: hands with the palms facing up are not identical

what is the factor needed to identify if a molecule is chiral

if the carbon is bonded to 4 different things

are these figures chiral or achiral

achiral

are these figures chiral or achiral

chiral

what is true about chiral molecules and carbohydrates

every monosaccharide has at least one chiral carbon

what are different isomers called (chiral)

enantiomers

how do you turn a fischer projection into its enantiomer

flip all the OH and H groups

the second to last carbon’s hydroxyl group being on the right side indicates that it is D or L isomer?

D isomer

the second to last carbon’s hydroxyl group being on the left side indicates that it is D or L isomer?

L isomer

what determines the identity of a chiral carbohydrate on a fischer projection

the orientation of the middle hydroxyl groups around the chiral carbons

what are the three most important carbohydrates?

D-glucose, D-galactose, D-fructose

what are essential facts about D-glucose

• dextrose

• found in blood, fruits, honey

• basic building block for essential di and polysaccharides (cellulose, sucrose, glycogen, lactose, amylose)

What are essential facts about D-galactose

• found in lactose

• essential for membranes in the brain and nervous system

important fact about D-fructose

the sweetest natural carbohydrate that is found in fruits

what are haworth projections

a fischer projection that is turned clockwise by 90 degrees (on its side)

If the OH group is up on the first carbon what kind of isomer is the haworth projection

beta isomer

if the OH group is down on the first carbon what kind of isomer is the haworth projection

an alpha isomer

what is the process in which di- and polysaccharides are split up back into monosaccharides that uses acid or enzymes

hydrolysis

what is the other reactant necessary to perform a hydrolysis reaction other than the di- or polysaccharide?

water

are monosaccharides able to be oxidized and or reduced?

yes

an aldose that can be oxidized is called

a reducing sugar

what are prime examples of reducing sugars

glucose, fructose, and galactose

what is the product of an aldose being oxidized?

aldehyde becomes a carboxylic acid

what is the name change during an oxidation reaction of an aldose

-ose ending turns into -onic acid

what can fructose do to become a reducing sugar

rearrange to become a glucose (changing from a ketose to an aldose) ketohexose

how is a monosaccharide reduced

when a monosaccharide reacts with H2 (hydrogen gas) and platinum to be converted into an alditol (sugar alcohol)

what is the name change when the monosaccharide becomes an alditol

-ose to -itol

what does alpha(1→4) indicate

the first monosaccharide is the alpha isomer and is connected to the 4th carbon of the other monosaccharide in the form of a glycosidic bond to form the linkage

what is a reducing sugar

a carbohydrate that contains a free aldehyde or ketone group that allows it to act as a reducing agent, donating electrons to other molecules to cause them to be reduced

are all monosaccharides reducing sugars?

yes

what are the four most important biological polysaccharides

amylose, amylopectin, cellulose, glycogen

facts about amylose

• starch found in plants

• straight chain of glucose molecules connected by alpha (1→4) glycosidic bonds

• no branching

amylopectin facts

• starch found in plants

• made of glucose connected by alpha (1→4) glycosidic bonds

• glucose chains have branches that connect by alpha (1→6) glycosidic bonds

glycogen facts

• found in animals

• has more branches than amylopectin

• stored in our livers and muscle tissue

cellulose facts

• gives structure to plants

• made of straight chains of glucose connected by beta(1→4) glycosidic bonds

• due to body not producing the correct enzyme, cannot hydrolyze cellulose into glucose

what is the process of glucose being digested

glucose → blood stream → energy

what is the process of a polysaccharide being digested

polysaccharide → hydrolysis → monosaccharides → blood stream → energy

how is high blood sugar digested

high blood sugar → insulin released → dehydration of glucose to form glycogen

how is low blood sugar digested

low blood sugar → glucagon released → glycogen hydrolyzed to make glucose