M2 Lesson 1 - Definition, Sources, Properties and Functions of Carbohydrates

Carbohydrates

represent a broad group of substances that include sugars, starches, gums, and celluloses.

carbon, hydrogen, and oxygen

The common attributes of carbohydrates are that they contain only the elements ____________________ and that their combustion will yield carbon dioxide plus one or more molecules of water.

polyhydric alcohols.

Chemically carbohydrates are aldehydes or ketone derivatives of

Glucose

is the most important carbohydrate

polyhydroxy

Carbohydrates, called sugars and starches, are ________ aldehydes or ketones, or compounds that can be hydrolyzed to them.

Disaccharides

are composed of two mono-saccharide units joined together.

Polysaccharides

are composed of three or more monosaccharide units joined together.

photosynthesis

Carbohydrates are synthesized in green plants by ______, whereby energy from the sun is stored as chemical energy in carbohydrates.

bursts of energy

In the body, carbs are used for ________ needed during exercise in the form of glucose.

Monosaccharides

the simplest carbohydrates

3 to 6

Monosaccharides generally have____ C atoms in a chain with an aldehyde or ketone ending and many –OH groups

aldoses

Aldehyde monosaccharides are

ketoses

ketone monosaccharides are

glyceraldehyde

The simplest aldose is

dihydroxyacetone

The simplest ketose is

glyceraldehyde

what is this?

dihydroxyacetone

what is this?

triose

has 3 C’s

tetrose

has 4 C’s

pentose

has 5 C’s

hexose

has 6 C’s

aldotriose

Glyceraldehyde is an

ketotriose

Dihydroxyacetone is a

sweet

Monosaccharides are ____ tasting, but their relative sweetness varies greatly.

Monosaccharides

are polar compounds with high melting points.

very water soluble

The presence of so many polar functional groups capable of hydrogen bonding makes the monosaccharides