BIOCHEMISTRY (CARBOHYDRATES)

carbohydrates

major bio-organic molecules

TRUE

carbohydrates are created by photosynthetic plants utilizing carbon dioxide and water

FALSE

carbohydrates accounts for 80% of the mass of dry plant material

polyhydroxy aldehydes & polyhydroxy ketones

carbohydrates are BLANK or BLANK (kind of organic compounds)

CELLULOSE

carbohydrates serve as structural components in plant in the form of BLANK

STARCH

carbohydrates is a source of energy reserves for the plant in the form of BLANK

Oxidized

Carbohydrates gives energy when BLANK

proteins, lipids and nucleic acid

carbohydrates provide carbon atoms to produce other compounds like BLANK BLANK BLANK

true

Carbohydrates is a component of the nucleotides of DNA and RNA molecules (T or F)

false (lipids)

carbohydrates are associated with proteins as essential component of cellular membrane

false (proteins)

for cell to cell and cell to molecule identification when linked to protein

monosaccharide

disaccharide

trisaccharide (oligosaccharide)

polysaccharide

classifications of carbohydrates based on size

monosaccharide

consist of one sugar unit either ketose or aldose

False

monosaccharide go through hydrolysis to produce simplex sugar units (true or false)

3 - 7 carbon atoms

5 & 6 most prevalent

monosaccharide contains BLANK carbon atoms with BLANK are the most prevalent

TRUE

in pure form monosaccharide are crystalline, water soluble and white solid substances (t or f)

monosaccharide

ribose, fructose, glucose are example of BLANK

disaccharide

has 2 monosaccharide units that are covalently attached to one another

FALSE

disaccharide are not crystalline and insoluble in water

disaccharide

lactose and sucrose are example of BLANK

trisaccharide (oligosaccharide)

yields 3 monosaccharides after hydrolysis

trisaccharide

raffinose is example of BLANK

Polysaccharide

comprised of numerous monosaccharide units that are covalently bonded to each other.

polysaccharide

starch, cellulose, glycogen, chitin, heparin and hyaluronic acid is an example of BLANK

monosaccharide

simplest type of carbohydrates

TRIOSE - 3

TETROSE - 4

PENTOSE - 5

HEXOSE - 6

Classifications of monosaccharide based on the number of carbon atoms

mirror images

what do you call the right and left handed forms

superimposable

images where points of the image coincide when the images are superimposed onto one another.

non-superimposable

images where not all points coincide when the images are stacked above one another.

chiral center

an atom in a molecule where four different groups of atoms bonded to it.

TRUE

in achiral molecules, handedness does not exist

Stereoisomerism

refers to isomers with identical molecular and structural formulas but different atom orientations.

1. Enantiomers

2. Diastereomers

Two types of stereoisomers:

Enantiomers

are stereoisomers with molecules that cannot be superimposed on top of one another.

Diastereomers

are stereoisomers, but they don't have molecules that are mirror image of one another.
Diastereomers include cis trans isomers.

optically active.

A substance that rotates the plane of polarized light is said to be BLANK

rDextrorotatory

• compound is a chiral compound that rotates the plane of polarized light to the right

• Levorotatory

• compound is a chiral compound that rotates the plane of polarized light to the left

Glyceraldehyde

A compound only contains one asymmetric carbon atom. Therefore, two stereoisomers are possible.

Epimers:

sugars that differ in configuration only at a single asymmetric carbon atom.

D-Glyceraldehyde and Dihydroxyacetone

The simplest monosaccharides

One of the intermediates of glycolytic pathway-

glycolytic pathway

a pathway of reactions where glucose is converted into two molecules of pyruvate).

Glucose

Most abundant in nature and the most important from a human nutritional standpoint.

20%-30%

Percentage of glucose by mass in ripe fruits

Glucose

Also known as dextrose (optically active D-glucose rotates the plane-polarized light to the right) and blood sugar (blood contains dissolved glucose normally in the range of 70-100 mg/dL).

D-Galactose

Synthesized from glucose in the mammary glands for use in the production of lactose (milk sugar), a disaccharide that consists of a glucose and a galactose units.

D-Galactose

Part of the glycoproteins-protein-carbohydrate compounds found in brain and nerve tissue.

D-Galactose

Component of chemical markers that distinguish various types of blood—A, B, AB, and O

D-Fructose (levulose)

A ketohexose. It is also known as BLANK and fruit sugar.

D-Fructose

Sweetest among the sugars

D-Ribose

an Aldopentose sugar

Component of ribonucleic acids (RNAs) and adenosine triphosphate (ATP).

intramolecular reaction

hemiacetal

Cyclic formation results from the BLANK between the carbonyl group (aldose) and a hydroxyl group to form BLANK

0.01%

63%

37%

37%

Less than BLANK of the molecules are in the open-chain state,

and BLANK of the molecules are -D-glucose, BLANK are -D glucose, and BLANK are -D glucose when equilibrium is reached.

5 & 6

• While D-fructose and D-ribose both make BLANK-membered rings, galactose, like glucose, produces a BLANK-membered ring.

True

Other ketoses with enough carbon atoms, such as fructose, can also cycle. (T or f)

mutarotation

The process of converting back and forth from an a anomer to the open form to the ® anomer is called BLANK

pyranose & furanose

cyclic monosaccharides with six-atom rings are referred to as BLANK and those with five-atom rings as BLANK.

tollens & benedicts

Weak oxidizing agents, such as BLANK and BLANK solutions, oxidize the aldehyde end of an aldose to give an aldonic acid.

Strong & nitric acid

A monosaccharide's carbonyl group and the terminal primary alcohol group can both be oxidized simultaneously by BLANK oxidizing agents, such as BLANK, to yield a dicarboxylic acid.

Enzymes ( enzymatic oxidation)

In biological systems, BLANK can produce an alduronic acid by oxidizing the primary alcohol end of an aldose, such as glucose, without also oxidizing the aldehyde group. D-glucuronic acid is the end product of this oxidation of glucose.

hydrogen

Using BLANK as the reducing agent, the carbonyl group that is present in a monosaccharide (either an aldose or a ketose) can be converted to a hydroxyl group.

D-sorbitol

Chewing gum also contains BLANK as a sweetener.

Maltose

• Often called malt sugar, intermediate product of starch degradation.

• Made up of two D-glucose units joined by a (là 4) linkage.

• With reducing activity

Cellobiose

intermediate product in the hydrolysis of the polysaccharide cellulose contains two D-glucose units joined by B (1à4) glycosidic bond.

Lactose

• Consists of a B (1 →> 4) glycosidic linkage between a B-D-glucose unit and a B-D-galactose unit.

• The main sugar present in milk

Sucrose

• Common table sugar, is the most abundant of all disaccharides.

• Composed of a-D-glucose and B-D-fructose joined by uß(1 à2) glycosidic linkage.

• Non reducing sugar

Polysaccharides

• Also known as glycans

• May be homoglycan or heteroglycan

Homogylcan

Heteroglycan

• BLANK (only one type of monosaccharide monomer is present) or BLANK (more than one (usually two) type of monosaccharide monomer is present.

Starch

Containing only glucose monosaccharide units. It is the energy-storage polysaccharide in plants.

Glycogen

• Contains glucose units only.

• Also composed of a (1→4) and a (1→6) linkages

• Highly branched more than amylopectin

• Present in muscle and liver.

• Glycogenesis-

metabolic pathway that synthesizes glycogen.

Cellulose & Cellulase

• The most common naturally occurring polysaccharide and an essential structural component of plant cell walls.

• Cannot be digested by humans since BLANK is not present.

Chitin

• Give rigidity to the exoskeletons of crabs, lobsters, shrimp, insects, and other arthropods.

• Composed of N-acetyl glucosamine as monomeric unit joined B (1→ 4) glycosidic linkages.

Hyaluronic acid

Contains alternating residues of N-acetyl-p-D-glucosamine and D-glucuronic acid.

Highly viscous; serves as lubricants in the fluid of joints and they are also associated with the jelly-like consistency of the glassy humor of the eye.

Heparin

• An anticoagulant; it helps prevent blood clots; it binds strongly to a protein involved in terminating the process of blood clotting, thus inhibiting blood clotting.

• Composed of repeating units of D-glucuronate-2-sulfate and N-sulfo-D-glucosamine-6-sulfate

Glycolipids

Lipid molecule that has one or more carbohydrate (or carbohydrate derivative) units covalently bonded to

GLYCOPROTEINS

Protein molecule that has one or more carbohydrate (or carbohydrate derivative) units covalently bonded

carbohydrates

The BLANK portion of the glycolipid or glycoprotein serves as a marker on the outer cell membrane surface, while the lipid or protein portion is integrated into the structure of the cell membrane.