Carbohydrates Flashcards
What is the primary function of carbohydrates
Provide the body with energy (ATP)
Most of the carbohydrates you eat are digested and broken down into …
Glucose
Excess glucose can be stored for later use as
Glycogen. (animals)
Why can indigestible carbohydrates be good for our health?
Create soft, bulky stool that easily moves through the large intestine. Helps delay the absorption of other carbs in your digestive tract, thereby preventing blood glucose spikes.
Carbohydrates are made up of smaller units called
Monosccharides.
Monosaccharides consist of
Carbon, hydrogen and oxygen.
In general, they have one carbonyl group C=O and the remaining carbons each bear 1 hydroxyl group -OH.
Carbonyl can vary in location (aldose connected to H, usually on the end and ketones connected to something other than H. Usually in the middle.)
How to name monosaccharides based on the number of carbons
3- triose
4- tetrose
5- pentose
6- hexose
Glyceraldehyde is a
Triose
Ribose is a
Pentose
Glucose is a
Hexose
Oligosaccharides
A carbohydrate whose molecules are composed of a relatively small number of monosaccharide units. (3-12 monosaccharides)
In order to form disaccharides, oligosaccharides and polysaccharides, monosaccharides under go ____ reactions
Condensation reactions. Specifically, dehydration reactions. The joining of two molecules with the loss of water.
Glycosidic bonds
Bond formed between a hydroxyl group of one molecule and the anomeric carbon of another.
Anomeric carbon
CHOH. This carbon derived from the carbonyl carbon (ketone or aldehyde)
Carbohydrates tend to form ring structures in which kind of solution
Aqueous due to acid and bases in the water. In water, the ring can open and form spontaneously. Alpha or beta products can be produced.
3 disaccharides
Maltose= glucose + glucose Sucrose= glucose + fructose Lactose= galactose + glucose
Difference between glycoproteins and glycosaminoglycan
Glycoproteins are majorly composed of proteins.
Glycosaminoglycans are majorly composed of sugars.
What type of bond is a glycosidic bond
Covalent
Examples of oligosaccharides
Immunoglobin, mucin
Where are oligosaccharides primarily located
On the surface of cells or in the extracellular matrix
Oligosaccharides vs polysaccharides
Oligosaccharides consist of 3-12 monosaccharides and polysaccharides consist of 12 or more
Characteristics of glycogen
Composed of alpha glucose monomers with extensive branching. Storage form of glucose in animals. Located mainly in liver and muscle.
Starch
Composed of alpha glucose monomers with branching (amylopectin) or without branching/linear (amylose). This is the storage form of glucose in plants.
Cellulose
Composed of beta-glucose monomers with no branching. Humans are unable to digest cellulose due to lack of enzymes that are able to break down beta-glucose linkages. Instead, this contributes to the formation of dietary fiber.
Other names for glycosaminoglycans
GAGs, mucopolysaccharides
What are glycosaminoglycans composed of
Repeating disaccharide units - amino sugar and ironic acid OR galactose without branching.
5 GAGs
Chondroitin sulfate - most abundant GAG Keratin sulfate Dermatan sulfate Heparan sulfate Hyaluronate (only GAG that is not sulfated)
Characteristics of GAGs
Highly negatively charged. Attracts water. Functions as a high lubricant or shock absorber due to its high viscosity and low compressibility.
Role in the body
Primarily located on the surface of cells or in the ECM. Fills the space of the ECM in the form of hydrated gel.
Most GAGs, with the exception of hyaluronate, are linked to a core protein, forming ___
A proteoglycan. GAGs extend perpendicular from the core protein in a bottle brush-like structure. Examples- aggrdcan, lumina, keratocan, mimican, decor
What GAG cannot bind to protein to form a proteoglycan?
Hyaluronate
Difference between alpha and beta linkage
Beta is up in the air (birds in the sky) and alpha is pointed down (fish in the sea.. bc alpha looks like a fish)
