Carbohydrates

What is the main def of carbohydrates?

called sugars and starches, are polyhydroxy aldehyde or ketones, or compounds that can be hydrolyzed to them

What are the simplest carbohydrate?

monosaccarides

What are the two other saccardies?

1. Disaccarides: composed of 2 monosaccharide units joined together

2. Polysaccarides: composed of 3 or mroe monosaccharide units joined together

Where are carbohydrates synthesized from?

green plants: by photosynthesis where by energy from the sun is stored as chemical energy in carbohydrates

body: used for burst of energy needed during exercise in the form of glucose

How is monosaccharides built out?

• simplest carbohydrates

• generally 3-6 C atoms

• with aldehydge or ketone ending and many -OH groups

• Aldehyde → alduses

• Ketone → ketoses

How are monosaccharide characterized?

by the number of carbons in its chain

• 3 Carbons: triose

• 4 Carbons: tetrose

• 5 Carbons: pentose

• 6 Carbons: hexose

What are general characteristics of Monosaccharides?

• sweet tasing

• polar compounds with high melting points

• presence of so many polar function groups capable of hydrogen bonding makes monosaccharides very water soluble

What are the prefixes used for monosaccharides?

D: used when the OH group is drawn on the right side of the carbon chain

L: used when the OH group is drawn on the left side of the carbon chain

• use sugar that is farthest away from the carbonyl group

What group is all naturally occuring sugars?

D group

• glucose is blood sugar and the most abundant monosaccharide

• excess glucose is sotred as the polysaccharide glycogen or as fat

What is the cyclic form?

• OH and C—O groups can react together to form a ring

• rings are stable, when they contain 5 or 6 atoms

• D-glucose the OH group on C5 reacts with the carbonyl carbon to form a 6 membered ring

What is the anomeric carbon?

C atom that is part of a new center

• alpha isomer has OH down

• beta isomer has the OH up

Rings are called the Hayworth projections

What rings does aldopentos and keton exoses form?

5 not 6 membered rings

What are disaccharides?

carbohydrates composed of 2 monosaccharides

• formed when a -OH group of one monosaccharide reacts with the OH group of a second monosaccharide

Glycodic Linkage bond that joins them together

What can glycosidic linkage of the two rings be?

alpha or beta

• if the bond is alpha, glycosidic bond points down

• if the bond is beta, the glycosidic bond points up

What does Hydrolysis do?

cleaves the C-O glycoside bond and forms 2 monosaccharides

• hydrolysis of maltose yields 2 glucose molecules

What does Polysacccharides do?

contains 3 or more monosaccharides joined togheter

• 3 prevalent polysaccharides in nature are: cellulose, starch, glycogen

• each of these are made up of repeating glucose units joined by glyrosidic bonds

What is important about cellulose?

Unbranded polymer made up of repeating gllucose units joined by 1-4 Beta-glycosidic linkages

• formed in the cell walls of all plants, where it gives support and rididity to wood, plants stems, and grass

• humans do NOT posses the enzyme to hydrolyze cellulose and cannot digest it

• cellulose makes up the insoluable fiber in our diets which is important in adding bulk to waste to help eliminate it more easily

What is starch?

polymer made up of repeating glucose units joined by alpha - glycosidic linkages

• present in: corn, rice, wheat, potatoes

What is important about blood types?

A, B, AB, O

• blood type is based on 3 or 4 monosaccharides attached to a membrane protein of red blood cells

What are Fats and Lipids?

biological compounds that are very non polar

• contain a larger number number of C-C and C-H

What characteristics does lipids have?

soluable in organic solvents and insoluable in water

• thier identity is unique because its based on physical property rather than a functional group

How can lipids be categorized?

1. Hydrolyzable: can be converted into smaller molecules by hydrolysis with water (waxes, triascyligerol, phopholipid)

2. Nonhydrolyzable: lipids cannot be cleaved into smaller units by water. Tend to be more varied in structure. Includes steriods and fat soluabble vitamins

What are fatty acids?

carboxylic acids with long carbon chains of 12 - 20 carbon atoms

1. Saturated: fatty acids have no alkene in thier hydrocarbon chains

2. Unsaturated: fatty acids have one or more double bonds in their long hydrocarbon chains

What can unsaturated fatty acids by classified as?

omega - n

• n is the carbon at which the FIRST double bond occurs in the carbon chain, beginning at the end of the chain taht contains the CH3 group

What are waxes

1. Esters formed from fatty acids and a high molecular weight alcohol

   1. protective coat on feathers for birds to make them water repellent and leaves to prevent evaporation

   2. Beeswax, a complex mixture of 200 different compounds, contains the wax myrical pamitate at major component

What are triacylglycerols - fats and oils?

Triesters formed from gylcerol and 3 molecules of fatty acids

• fats and oils are triacylglycerols

• fats are derived from fatty acids having few double bonds high melting point, solids at room temperature

• oil from fatty acids have many double bonds, lower melting points, and liquids

What are steroids?

are a group of lipids whose carbon skeleton contain 3 - 6 membered rings, 1- 5 membered rings

• there are 17 ring carbonds and 2 more carbons as two Ch3 groups on most steriods

Cholesteral is the prominent member of the steroid family

• synthesized in the liver and found in almost all body tissue

What should be the daily in take of Cholesterol?

Less than 300 mg

• average american diet includes 400-500 mg each day

What are characteristics of Cholesterol?

• insoluable in aquesous medium blood

• one polar OH group and many non polar C-C, C-H

In order to be transported, cholesterol combines with phospholips and proteins to form water-soluble spherical particles call lipoproteins

What are lipoproteins?

Cholesterol combines with phospholipids and proteins to form water soluable spherical particles

• classified based off their density (LDL and HDL)

• HDL: contain more protein and much more cholestral than LDL

• Excess LDL cause cholesterol to form plague on the walls of arteries