Biochemistry Lab Act 7 and 8

Heterogenous group of naturally occurring substances

Characterized by their solubility in water and their solubility in nonpolar solvents such as ether, chloroform, benzene, and hot alcohol

Nonpolar solvents

Important dietary constituents not only because of their high energy value but also because of the fat-soluble vitamins and the essential fatty acids contained in the fat of natural foods

Efficient source of energy in the body

Fats are stored in the _______

Serves as a thermal insulator in the subcutaneous tissues and around certain organs

Set as electrical insulators allowing rapid propagation of depolarization waves along myelinated nerves

The fat content of ______ is particularly high

Combinations of _______ and _______ are important cellular constituents occurring both in the cell membrane and in the mitochondria within the cytoplasm

Combinations of _______ and _______ serve as a means of transporting lipids in the blood

Combination of fats and proteins

Classification of lipids

Esters of fatty acids with various alcohols, which include triacylglycerols or triglycerides and waxes

Plant-derived triglyceride

Animal-derived triglyceride

Esters of fatty acids with alcohol plus other groups

Lipids which contain a phosphoric acid residue

Example of phospholipids

Compounds of the fatty acids with carbohydrates, containing nitrogen

Example of glycolipids

Lipids associated with proteins

Refer to derivatives obtained by hydrolysis of simple and compound lipids as long as they still possess the general physical characteristics of lipids

Examples of derived lipids

Do not contain multiple bonds in their structures

Examples of saturated fatty acids

Structures similar to saturated fatty acids but contain at least one or more double bonds

Examples of unsaturated fatty acids

The oil that is rich in unsaturated fatty acid

Obtained from incomplete esterification of glycerol by various fatty acids

Compounds which contain the cyclopentanoperhydrophenanthrene nucleus

Most important member of the steroid group

Occur in animal fats

Present in blood and its abnormal level is related to atherosclerosis

Other related compounds

The ______ of lipids includes the detection of certain characteristic groups using different chemical reactions

__________ react with halogens such as Bromine via addition to the double bonds

The reaction between unsaturated fatty acid and halogens will result in the decolorization of the _____

The presence of Glycerol grouping as in coconut oil can be detected by means of _______

Test where the glycerol group is oxidized

_______ is formed when the glycerol group is oxidized and has a characteristic acid, irritating odor

_______ and ________ are usually differentiated from waxes by means of an acrolein test

Do not contain the glycerol grouping

________ gives characteristic colored condensation products with Acetic anhydride and concentrated sulfuric acid following the Lieberman-Burchard reaction

In the Lieberman-Burchard reaction, a positive result yields a _________ solution

Vitamin A is detected by the ________ reaction

The _______ reaction involves a series of color changes until finally a pink solution is obtained

Used to determine tocopherols (vitamin E) in foodstuffs

In the modified Furter-Meyer test, the ______ color which develops is specific for tocopherols

In the modified Furter-Meyer test, the ______ color which develops is specific for carotenoids and certain sterols

Polymers of amino acids

Polymers of monosaccharides

Very complex substances of high molecular weight, which on hydrolysis yield many molecules and many kinds of amino acids in addition to other products of decomposition

Hydrolytic changes are produced by ________

Certain ________ reactions are utilized to characterize proteins and their constituent amino acids

Groups present in certain ________ and _________ react with a variety of reagents forming colored products

Not all ________ contain the same amino acids and for this reason the different color reactions will yield products varying in color intensity according to the nature and amount of groups contained in the particular protein

Powerful oxidizing agent

Reacts with all α-amino acids and proteins to give an intense blue or purple colored compound

Ninhydrin reacts with all α-amino acids and proteins to give an intense _________ colored compound

Test that depends upon the presence of a-amino acids

Most general and one of the most sensitive reactions known for the qualitative detection of proteins and their hydrolytic products

The amino acids _________ and __________ react with Ninhydrin to give the yellow color

In the presence of a free carboxyl group adjacent to the amino group such as is present in a-amino acids quantitative amounts of CO₂ are released and this reaction has been used by __________ as a basis for a ___________

The Ninhydrin reaction was also given by __________ but without the liberation of CO₂

Given by the substance Biuret obtained upon heating urea to 180°C

NH₄OH (Ammonium hydroxide) dissolves Cu(OH)₂ (Copper hydroxide) to form ________

Proteins dissolve Cu(OH)₂ (Copper hydroxide) in ________ to form compounds of different colors

The reaction involves the nitration of the benzene nucleus and the formation of a yellow to orange color rendering the resulting compounds alkaline

_________ and __________ are the only amino acids that give the Xanthoproteic test very readily and strongly

In the Xanthoproteic test, the _______ gives more of a red color that does tyrosine

In the case of tryptophan in the Xanthoproteic test, there is a partial oxidation of the substance by _______

_________ which contains the benzene ring is nitrated with extreme difficulty into a colorless compound by nitric acid alone

If one adds a small amount of concentrated sulfuric acid together with the nitric acid to _______, one obtains a good positive test on making the mixture alkaline

The reaction is given by most of the monohydroxybenzene derivatives and to some extent by some dihydroxybenzene derivatives

With Phenol and Tyrosine, Millon's reaction is very marked and characteristic in that the color develops gradually from ________ to _________

In dihydroxybenzene such as Resorcin or of an indole derivative in Millon's reaction, no such red color is obtained but a ________ to a ________

__________ is the only monophenol derivative found in proteins

The reaction where Tryptophan is present and condenses with a number of aldehydes like Glyoxylic acid in the presence of concentrated H₂SO₄ (sulfuric acid)forming a violet complex

In the Hopkins-cole reaction, chemically pure __________ must be used since excessive amounts of oxidizing substances such as nitrites, nitrates, chlorides, and chlorates in impure acid interfere with the test

The addition of ________ and _________ to a solution containing free tryptophan results in the formation of a pinkish-lavender or violet color in the alcohol layer

In the presence of excess bromine water, the ________ color disappears and it may be masked by the color reagent

Sulfanilic acid reacts with HONO in the cold forming diazobenzene sulfonic acid by a process known as _____________

Formed from NaNO₂ (Sodium nitrite) and HCI (Hydrochloric acid)

In the Pauly reaction, ___________ and ____________ react forming red or purple condensation products

When an organic derivative of _________ is treated with a strong _________ solution, the substance is hydrolyzed according to the equation: RSH+2NaOH=ROH+Na₂S+H₂O

The only amino acids thus far obtained from proteins which contain reduced sulfur are ________ and ________

It is usually considered a _________ test as applied to proteins or amino acid mixtures to be a test for cysteine or cystine

The sulfur of __________ is not readily removed by alkali and is not affected by the reduced sulfur reaction

In this reaction, substances which contain the guanidine group, react with a-naphthol and an oxidizing agent such as sodium hypobromite to give a red or orange color

What color gives off in the Sakaguchi reaction?

Arginine, either free or combine in proteins, responds __________ to the test