Exam 1 Terms Flashcards
Sugar
molecules in carbohydrates that the elements carbon, hydrogen, and oxygen form in
Monosaccharide
carbohydrates that are composed of 1 simple sugar molecule. They are characterized by how many carbon atoms they contain. But usually the most important and numerous contain 5 (pentose) or 6 (hexose) carbon atoms
Disaccharide
carbohydrates composed of 2 sugar molecules. They are characterized by how the molecules are hooked together. Ex. maltose, cellobiose, sucrose and lactose.
Polysaccharide
carbohydrate composed of 3 or more sugars. 3 major polysaccharides are starch, glycogen, and cellulose.
Starch
repeating units of maltose (which in turn was repeating units of glucose) connected with alpha bonds, so it is all glucose. Polysaccharide. Primary digestible polysaccharide in plants. amylose and amylopectin
Cellulose
polysaccharide high in cell walls. beta bonds of glucose
Glycogen
highly branched chain polysaccharide of glucose in animals (similar to amylopectin). Ready energy source. Stored in animal cells. Amount is very limited
Glucose
hexose (contains 6 carbon atoms); most important sugar; found free in nature; it is blood sugar; many complex sugar molecules contain glucose; monosaccharide
Ribose
sugar molecule in DNA and RNA. Most important molecule because DNA is genetic material of life. From nutritional point of view it is non-remarkable and not essential in the diet. Though it’s crucial in living cells we don’t need to eat any because the body will form it from other substances in the metabolism in the body
Fructose
hexose (contains 6 carbon atoms); it is found both combined and free in nature. It is combined with glucose in table sugar and it is high in semen to support sperm. monosaccharide from fruit.
Galactose
hexose (contains 6 carbon atoms); only found combined in nature. It is combined with glucose in milk. monosaccharide
Maltose
disaccharide composed of 2 units of glucose connected by an alpha bond
Cellobiose
disaccharide composed of 2 units of glucose connected by a beta bond. repeating units of cellobiose. No animal makes an enzyme that can digest beta bonds (except some bacteria). The beta bond imparts a structural rigidity that makes the fibrous nature so different from starch
Hemicellulose
polysaccharide Up to 40% of CHO in forages. Complex mix of glucose, xylose, mannose, arabinose, galactose. Principle component of plant cell walls. easier to digest than cellulose, but allied with lignin
Lignin
totally indigestible polysaccharide
Amylase
enzyme that helps digest carbohydrates; it catalyzes the hydrolysis of starch into sugars
Amylopectin
polysaccharide starch branched chain molecule
Amylose
polysaccharide starch straight chain molecule
Cellulase
refers to a group of enzymes which, acting together, hydrolyze cellulose. Cellulose is a linear polysaccharide of glucose residues connected by β-1,4 linkages.
Xylose
pentose (5 carbon atoms) monosaccharide
Mannose
hexose (contains 6 carbon atoms) does not occur free in nature but occurs combined in polysaccharides; monosaccharide
Acetic Acid
volatile fatty acid, important in rumen fermentation, with 2 carbon atoms - CH3COOH
Butyric Acid
volatile fatty acid, important in rumen fermentation, with 4 carbon atoms - CH3CH2CH2COOH
Palmitic Acid
long chain saturated fatty acids with 16 carbon atoms - CH3(CH2)14COOH
Stearic Acid
long chain saturated fatty acids with 18 carbon atoms - CH3(CH2)16COOH
Oleic Acid
long chain unsaturated fatty acid that is not essential with 18 carbon atoms and 1 double bond
Linoleic Acid
long chain unsaturated fatty acid that is an essential fatty acid with 18 carbon atom and 2 double bonds
Arachidonic acid
long chain unsaturated fatty acid that is an essential fatty acid with 20 carbon atoms and 4 double bonds
Essential Fatty Acid
ong chain unsaturated fatty acids: linoleic acid (18 carbon atoms, 2 double bonds), linolenic acid (18 carbon atoms, 3 double bonds), arachidonic acid (20 carbon atoms, 4 double bonds)
Glycerol
a simple monomer of fats; found in triglycerides
propionic acid
volatile fatty acid, important in rumen fermentation, with 3 carbon atoms - CH3CH2COOH
triglyceride (di-, mono-)
Glycerides are molecules of one glycerol with one (mono), two (di), or three (tri) fatty acids
Valine
Essential
Branched chain AA
Rare, inherited metabolic disease in which there is a failure of oxidative decarboxylation breakdown of valine, leucine, and isoleucine which results in maple syrup urine disease, named because of the characteristic odor in the urine.
an ideal protein would contain 70 to 80% as much valine as lysine.
Tryptophan
the second most limiting AA in corn diets for pigs
(First or second depending on circumstances)
Can be used to form the vitamin niacin.
Not relied upon to meet the animal’s needs. (This is because feeds are usually low in tryptophan and the synthesis is insufficient to meet their daily needs).
Useful in aiding sleep
Skatole and indole can be formed from it’s breakdown in large intestine by bacteria
(Foul odors)
Threonine
Essential
Third or fourth limiting AA in many cases
would become a limiting amino acid in corn diets for pigs if high levels of lysine, and possibly tryptophan and methionine, were supplemented replacing protein
Isoleucine
A branched chain amino acid.
An ideal protein would contain 1/2 as much isoleucine as lysine.
A rare, inherited metabolic disease in which there is a failure of oxidative decarboxylation (breakdown) of valine, leucine, and isoleucine results in maple syrup usrine disease, named because of the characteristic odor of the urine.
Methionine
Essential
A sulfur-containing AA
(Only one of the 10 essential AA’s)
Often not present in sufficient supply in feeds
A portion of the methionine requirement CAN be met from cystine (another sulfur-containing AA).
Can act as a methyl donor
(Involved in the synthesis of many important compounds in the body,
like epinephrine and choline).
“Ideal protein” consists of: ½ Methionine + cystine as lysine
Both D and L isomers are biologically active
Can be chemically synthesized and economically purchased for diets
Histidine
Essential
Contains an imidazole groups
Precursor of histamine
An “ideal protein” would contain 33% as much histidine as lysine.
Contains an imidazole group. It is a precursor of histamine.
Lysine
Essential tickets
The most important limiting AA in corn and most grains for swine and poultry.
Can buy lysine synthetic and add it to diets
Has to be created biologically.
Diets balanced for lysine will contains most other AA’s in excess of requirement
If natural sources of good quality proteins are used.
Leucine
Essential BUT abundant
Branched chain AA
Usually have more than we want
Abundant in corn protein and many other grain proteins, and is not therefore a
concern to supplement
Only the L isomer has a biological value.
“Ideal protein” would contain 100% leucine as lysine
Peptide bond
the bond through which amino acids connect; the OH from one amino acid and the NH from another become H20, connecting N to C (n-c terminus)
Polypeptide
multiple proteins linked together by peptide bonds
crude protein
N x 6.25 = Crude Protein
analysis of the amount of N and multiply the amount of N by 6.25; able to do this because proteins on average contain 16% Nitrogen - out estimate of true protein based on N content
True protein
complex things made of amino acid connected by peptide bonds in long, complicated chains
NPN
non-protein nitrogen
Ruminants can use NPN because the bacteria in the rumen can use it to build their own AA’s
Argenine
Essential
Precursor of the urea in the body
(Urea is the form in which nitrogen is removed from mammals)
Formation: with normal breakdown of protein and deamination of amino acids
Especially critical in cats
