Exam 3 Long Version Flashcards

1
Q

Enzyme

A

the biological chemical reaction catalyst. In the context of this chapter, an enzyme is an example of a bioactive protein

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2
Q

Insulin

A

A major metabolic hormone that is secreted in response to feed consumption and elevated blood glucose. In the context of this chapter, insulin is an example of a hormone whose structure is a protein

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3
Q

Amino acid

A

the fundamental “building block” of protein structure. There are 20 common amino acids in feeds and foods, and additional examples in animal tissues. Each amino acid contains an amino group on one side of the molecule and a carboxyl group on the other. Of the 20 different amino acids, there are 20 different “side chains” which are structures bonded to the same centralized carbon atom as the amine and carboxyl groups

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4
Q

Side chain

A

the structure on an amino acid that distinguishes it from the other 19 amino acids

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5
Q

Peptide

A

a protein that consists of less than 10 amino acids

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6
Q

Peptide bond

A

the amide bond that bonds amino acid to the next in a protein. Recall that the peptide bond occurs as a reaction between a carboxyl group and an amine group

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7
Q

Hydrolysis

A

in the context of this chapter, hydrolysis refers to the breaking of a peptide bond (amide bond) such that a water molecule is introduced into the reaction

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8
Q

Primary structure of a protein

A

the sequence of amino acids in the protein. Do not confuse sequence with composition.

Sequence is the order in which the amino acids occur from one end of the protein to the other.

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9
Q

Secondary structure of a protein

A

this refers to the changes in conformation or three dimensional structure that the protein begins to form as the primary structure grows.

Examples of secondary structure include helix and pleated sheets. These difference are determined by the primary structure because it’s the side chains of the amino acids that interact to form different three dimensional configurations

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10
Q

Tertiary structure of a protein

A

this refers to the final three dimensional structure of the protein after it has been synthesized. In order for tertiary structure to occur and be maintained, amino acid side chains interact with one another in specific locations through different types of bonding: hydrogen bonds, electrostatic interactions between polar residues, and by covalent bonds between Cys residues that form disulfide bonds.

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11
Q

Quaternary structure of a protein

A

this type of structure refers to two or more complete proteins combining to form a larger protein in which the individual proteins represent subunits of the larger, complete protein. Not all complete and functional proteins have quaternary structure. An example of a protein with quaternary structure is hemoglobin.

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12
Q

Glycine

A

An amino acid with a hydrogen atom as its side chain

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13
Q

Non-polar side chains

A

These are side chains of amino acids in which there is no polarity or charge.

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14
Q

Amino acids with non-polar side chains include: (8)

A
  1. Alanine (Ala)
  2. Valine (Val)
  3. Leucine (Leu)
  4. isoleucine (Ile)
  5. Proline (Pro)
  6. Tryptophan (Trp)
  7. Phenylalanine (Phe)
  8. Methionine (Met)
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15
Q

Imino group

A

Basically, an amino acid molecule contains an amine group. There is an “amino” acid in which the amine group is bonded to the central carbon of the amino acid, as well as to a carbon atom in the side chain such there is no true amino group. Such a nitrogen containing group is a “imino” group, and the amino acid identified with this type of structure is proline (Pro).

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16
Q

Polar side chains

A

these are amino acid side chains that contain polar groups, either positive or negative polarities (or charges).

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17
Q

Amino acids with polar side chains include: (4)

A

three amino acids contain hydroxyl groups:

  1. Serine (ser)
  2. Threonine (thr)
  3. Tyrosine (tyr)

and one amino acid contains a thiol group

  1. Cystein (cys)
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18
Q

Polar acid side chains (2)

A
  1. Glutamic acid (glu)
  2. Aspartic acid (asp)
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19
Q

Polar basic side chains (5)

A

three amino acids have amino groups on their side chains

  1. Glutamine (gln)
  2. Aspargine (asn)
  3. Lysine (lys)

one has an imino group on its side chain

  1. Histidine (his)

and one has a combination of amino and imino groups on its side chain

  1. Arginine (arg)
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20
Q

genetic code

A

the code for all proteins that is determined by the sequence of nucleic acids in the animal’s DNA

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21
Q

Transcribe

A

to copy from one form to another. In the context of this chapter, transcribing or transcription refers to reading the genetic code of the DNA and re-writing it chemically in a form that can then be directly used for making the protein designated by the genetic code

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22
Q

Nucleotide sequence

A

the sequence of the four nucleotides in DNA: adenine, guanine, thymine and guanine

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23
Q

Messenger RNA

A

the chemical copy of the genetic code of a small section of the DNA. When the genetic code section is transcribed, the result is the messenger RNA (mRNA). The “messege” is therefore written chemically in a form that can move to a location in the cell where a protein can be synthesized; this form is mRNA

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24
Q

Ribosome

A

a organelle in the cell outside of the nucleus where proteins are synthesized in a manner consistent with the genetic code as chemically written as the mRNA

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25
Q

Translation

A

the process in which the message of the genetic code that occurs (was transcribed) as mRNA is converted to a protein. For this process, an amino acid that occurs in conjunction with a sequence of three nucleotides will be used to build the new protein. In this way, the genetic code is translated into amino acid sequence specific for a give protein as indicated by the genetic code

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26
Q

Codon

A

A sequence of three nucleotides in the mRNA. For every amino acid there will be a specific sequence of three nucleotides. Therefore, the order that the nucleotides occur will determine the order of the amino acids that are added to the growing protein. In this way, the cell takes the genetic code, transcibes it into large groups of codons that ultimately determine which amino acids which will be used and in what order (sequence).

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27
Q

Post-translation modification

A

any changes to the structure of a protein after the initial translation of the gentic code to amino acid sequence has occurred. This is common for most proteins and involves number elaborate reaction steps

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28
Q

Sickle cell anemia

A

a genetic disease in which the primary structure of the protein subunits (quaternary structure) of hemoglovin is altered. In this dcondition, a glutamic acid (carboxylic acid side chain) is replaced with a valine (non-polar side chain). The resulting tertiary and quaternary structures cause the proteins to clump and take on a sickle shape. This also reduce the ability of the hemoglobin to bind oxygen; hence the anemia that also characterizes the condition.

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29
Q

Bioactive Molecule

A

any molecule in the animal’s cell or circulation that causes or induces a biochemical reaction. The best example of a bioactive molecule is an enzyme. Other examples include hormones, hemoglobin, myoglobin, and contractile proteins (muscle).

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30
Q

Essential Amino Acids

A

Any amino acid that cannot be made at all or in sufficient quantities to meet the requirements of the animal

  1. Arg- Arganine
  2. His- Histadine
  3. Ile- Isoleucine
  4. Leu- Leucine
  5. Lys- Lysine
  6. Met- Methanomine
  7. Phe- Phenoalanine
  8. Thr- Threonine
  9. Trp- Tryptophan
    1. Val- Valine
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31
Q

Non-essential amino acid

A

Amino acids that can be synthesized by the animal and thus do not need to be in the diet

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32
Q

Indispensable Amino acid

A

these are the same amino acids listed for essential amino acids. In non-ruminant animals, the essential and indispensabe amino acids are the same. In a ruminant, ruminal microbes convert dietary proteins to microbial proteins, which contain the essential amino acids, and do so regardless of the dietary amino acid composition. Thus, ruminant animals do not need to consume the essential amino acids; however, the essential amino acids are not made by the animal itself. Therefore, they remain indespensable to the animal.

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33
Q

enzymes

A

Specialized proteins of the cell that serve as the true reaction catalyst. Virtually all reactions have a specific enzymes. Enymes are at the root of metabolism and often it is an enzyme thatis the cause or result of disease

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34
Q

activation energy

A

the reaction energy required to initiate a biochemical reaction to the point that conversion to product(s) begins

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35
Q

transition state

A

the progression through the biochemical reaction where product formation occurs

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36
Q

substrates

A

the materials that are involved in the initial part of the biochemical reaction. Substrates are the same as reactants of a chemical reaction

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37
Q

Products

A

the end result of the biochemical reaction. the materials that occur from the reaction; materials could represent a single product of synthesis or multiple products of a degradation reaction, for example, hydrolysis

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38
Q

enzyme-substrate complex

A

often abbreviated as the ES complex, it represents the initial substance that develops when a substrate and the enzyme combine at the first part of the biochemical reaction

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39
Q

active site

A

the part of the enzyme’s three dimensional structure where the actual biochemical reaction takes place. The active site is where the substrate initially interacts with the enzyme to form the ES complex

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40
Q

Lock and Key Model

A

the theoretical mechanism of an enzyme and substrate interaction in which the substrate “fits” into the active site of the of the enzyme specifically based on the three dimensional structures of the substrate and the active site

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41
Q

Induced fit model

A

the theoretical mechanism of an enzyme and substrate interaction in which the first substrate that encounters enzyme causes a change in the enzyme’s three dimensional conformation so that subsequent interaction with more substrate occurs rapidly

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42
Q

Enzyme Specificity

A

different enzymes are synthesized to catalzye specific reactions. Usually, two different types of enzymes will not catalyze the same reaction.

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43
Q

glycosidic bond

A

in the context of this chapter, a glycosidic bond is an ether bond connecting two glucose molecules. There are two types of glycosidic bonds, alpha and beta

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44
Q

denatured protein

A

a protein that has lost its tertiary structure, mainly through disruption of hydrogen bonds and altered electrostatic interactions

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45
Q

Hydrolase

A

a class of enzyme that catalyzes a hydrolysis reaction

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46
Q

Isomerase

A

a class of enzyme that catalyzes a change in the structure of a molecule without changing its fomula

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47
Q

Ligase

A

a class of enzyme that catalyzes formation of obnds between carbon or other atoms

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48
Q

Lyase

A

a class of enzyme that catalyzes breaking of bonds between carbon atoms, as well as other atoms such as S and N

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49
Q

Oxidoreductase

A

a class of enzyme that catalyzes reactions involving oxidation and reduction

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50
Q

dehydrogenase

A

a class of enzyme that catalyzes oxidation and reduction reactions; this is an example of an oxidoreductase. However, there are numerous reactions involving different specific dehydrogenase enzymes

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51
Q

Transferase

A

a class of enzyme that catalyzes the transfer of certain functional groups from one molecule to another

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52
Q

First order catalysis

A

a type of catalysis in which the rate of the reaction is directly proportional to the concentration of substrate when the concentration of enzyme is held constant

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53
Q

allosteric enzyme catalysis

A

a type of enzyme catalysis in which the first substrates bind slowly and then the subsequent substrate bind rapidly and in proportion to the concentration of substrate

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54
Q

Sigmoidal Plot

A

a graph in which the curve is “S” shaped

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55
Q

Hyperbola

A

a graph in which the curve is a straight line through the origin

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56
Q

Competitive inhibition

A

inhibition of an enzyme catalyzed reaction in which the inhibitor material has a shape similar to the real substrate and inhibits by binding to the active site. With half and half substrate and competitive inhibitor, the two will compete for binding to the active site of the enzyme and result in about half the rate of product formation comparaed to the reaction with no inhibitor

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57
Q

Vmax

A

abbreviation for the maximum velocity of the enzyme catalyzed reaction. As the concentration of substrate increases, the reaction rate increases until the concentration of substrate has saturated all of the enzyme active sites, at which point, the reaction velocity slows down to a slope of the line of essentially zero

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58
Q

Km

A

abbreviation for a term called the “Michaeles Constant”. A Km is a value representing the concentration of substrate that supports a reaction velocity of one half the maximum velocity for that enzyme (Km= concentration for 1/2 Vmax)

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59
Q

Non-competitive inhibition

A

reaction inhibition in which the inhibitor binds to a location on the enzyme that is different from the substrate binding site (active site). The ability to bind substrate is not reduced, but the reaction velocity is decreased (Km is the same, but the Vmax is decreased)

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60
Q

Allosteric regulation

A

regulation of enzymes that have multiple binding sites for substrates and for regulatory substances

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61
Q

Positive effector

A

a regulatory substance that affects an allosteric enzyme by increasing reaction velocity

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62
Q

Negative effector

A

a regulatory substance that affects an allosteric enzyme by decreasing reaction velocity

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63
Q

Feedback Regulation

A

inhibition of an enzyme by a substance that is synthesized by a sequence of enzyme catalyzed reactions and in which the enzyme inhibited is the first one in the sequence. Usually, the substance synthesized is utilized so it does not accumulate; however, when need for the substance is decreased, it will accumulate. Thus, inhibition of the first enzyme in the sequence will slow down production of substance until more is needed by the cell.

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64
Q

Covalent Modification

A

regulation of an enzyme’s activity by bonding of a molecule to the enzyme via a covalent bond. The best example is the bonding of a phosphate to an enzyme through a phosphate ester created from the reaction of the phosphate and an alcohol on a serine of the enzyme protein. Some enzymes are more active and some are less active when this happens.

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65
Q

Phosphorylation

A

enzyme catalyzed addition of a phosphate molecule to another molecule, for example, addition of a phosphate to serine of an enzyme

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66
Q

Glycogen

A

a carbohydrate found in animal tissues that stores glucose for use as an energy substrate. Glycogen concentration is very very low because animals do not rely on store glucose for the bulk of their energy reserves (fat serves this purpose)

67
Q

Hormone-sensitive lipase

A

an enzyme found in muscle and fat cells that catalyzes hydrolysis of carboxyl ester bonds of fat. This enzyme is an example of one that increases in activity when it is phosphorylated

68
Q

Coenzymes

A

Non-protein substances that interact with enzymes to promote the biochemical reaction. Some minerals and most water soluble vitamins are coenzymes

69
Q

carbohydrate

A

substances that include starch, cellulose, and other materials that represent food, feed, and structural compononts. The basic structure has a formula CH2O and is best characterized by glucose

70
Q

Glucose

A

a molecule containing six carbon atoms with a formula (CH2O)6. Glucose is the principle carbohydrate of starch, cellulose, and glycogen, and is the carbohydrate of “blood sugar”.

71
Q

Gluconeogenesis

A

This is a sequence of biochemical reactions in which a molecule of glucose is synthesized from starting materials that are not carbohydrates. For example, some amino acids, propionate from the rumen, and glycerol from recycled fat can be converted into glucose in the liver of animals through gluconeogenesis

72
Q

Energy

A

a term that is used to describe substrates that are used to produce molecules that, upon their hydrolysis generate the ability to do work or perform reactions the results a physical action.

73
Q

alpha-glycosidic bond

A

the covalent, ether bond that connects glucose molecules of starch

74
Q

beta-glycosidic bond

A

the covalent, ether bond that connects glucose molecules of cellulose

75
Q

empirical formula

A

the most basic formula for a molecule or type of molecule. For example, all carbohydrates have an empirical formula of CnH2On where “n” is the number of C or H2O

76
Q

Monosaccharide

A

a sugar that contains a single carbohydrate molecule. For example, a single molecule of glucose is a monosaccharide

77
Q

Triose

A

A monosacccharide that consists of a three-carbon carbohydrate

78
Q

Tetrose

A

A monosaccharide that consists of a four-carbon carbohydrate

79
Q

Pentose

A

A monosaccharide that consists of a five-carbon carbohydrate

80
Q

Hexose

A

A monosaccharide that consists of a six-carbon carbohydrate

81
Q

Heptose

A

a monosaccharide that consists of a seven-carbon carbohydrate

82
Q

Polymer

A

a large structure made up of the same basic molecule

83
Q

Oligosaccharide

A

A carbohydrate polymer in which there are about ten molecules

84
Q

Polysaccharide

A

a carbohydrate polymer in which there are many molecules. For example, starch is a large polymer of glucose

85
Q

Disaccharide

A

a two-molecule polymer carbohydrate. For example, sucrose, a table sugar, is a disaccharide containing one glucose and one fructose

86
Q

Polyhydroxide aldehyde

A

a molecule that contains two functional groups, alcohol and an aldehyde; however there are many alcohol groups on the molecule

87
Q

polyhydroxy ketone

A

a molecule that contains two functional groups, alcohol and a ketone; however, there are many alcohol groups on the molecule

88
Q

Aldose

A

any monosaccharide that is a polyhydroxide aldehyde. For example, a single molecule of glucose is an aldose

89
Q

Ketose

A

any monosaccharide that is a polyhydroxide ketone. for example, a single molecule of fructose is ketose

90
Q

glyceraldehyde

A

a three-carbon aldose

91
Q

dihydroxyacetone

A

a three-carbon ketose

92
Q

Aldohexose

A

a six-carbon aldose. Glucose is an aldohexose because it is a six carbon aldose

93
Q

Hemiacetal

A

when a single aldohexose forms a cyclic or ring structure, the alcohol group of carbon number six reacts with the aldehyde group to connect the ends. This is the hemiacetal.

94
Q

Hemiketal

A

when a single ketohexose, such as fructose, forms a cyclic or ring structure, the alcohol of carbon number six reacts with the ketone group to connect carbon number six with the ketone at carbon number two. This is hemiketal.

95
Q

Anomeric carbon

A

the carbon atom in the cyclic structureof a hemiacetal that orginally was the aldehyde-carbon. for the cyclic structure of glucose (the ehmiacetal) the anomeric carbon is always carbon number one

96
Q

Glycosides

A

carbohydrate polymers that are formed through ether linkages (glycosidic bonds) connecting the various monosaccharides. For example, starch, cellulose, and even sucrose (a disaccharide) are glycosides

97
Q

Full acetal

A

when the anomeric carbon atom of a monosaccharide hemiacetal bonds to the alcohol of a different monosaccharide to form the ether linkage, the bonding changes from the hemiacetal to the full acetal. The full acetal, therefore is the ether linked glycosidic bond

98
Q

Cellulose

A

A large glucose polymer in which the glycosidic bonds of the full acetal have an orientation is refferred as the beta-glycosidic bond. Cellulose is common in cotton, wood, and forages

99
Q

Homopolysaccharide

A

A polysaccharide in which all of the monosaccharide units are the same molecule. For example, glycogen is a homopolysaccharide because each of the monosaccharide units is represented by only glucose

100
Q

Heterpolysaccharide

A

a plysaccharide in which the monosaccharide units are not all the same molecule

101
Q

Starch

A

a glucose polysaccharide in which the ether linked glucose molecules have the alpha-glycosidic bond orientation. Starch is common in corn, wheat, and other cereal grains

102
Q

Amylose

A

a glucose polymer linked together by only alpha-glycosidic bonds between carbon-one (anomeric carbon) of one molecule and carbon-four of the other molecule– the alpha (1–>4) glycosidic bond; amylose is a polysaccharide

103
Q

Amylopectin

A

amylose that also contains branches in which glucose units are connected via alpha(1–>6) glycosidic bonds

104
Q

Glycogen

A

the storage form of glucose in animal tissues. Structurally, glycogen is the same as amylopectin; however, in glycogen there are more branches.

105
Q

Cellulase

A

an enzyme produced by microorganisms, for example ruminal bacteria, that catalyzes hydrolysis of beta (1–>4) glycosidic bonds of cellulse

106
Q

ferment

A

the breakdown of a nutrient by microbes. In the rumen, microbes will produces enzymes that hydrolyze glucose molecules from starch and cellulose and then they will break the glucose down (ferment it) to generate energy and additional substrates for their continued growth. Fermentation produces byproducts that the host will use as well. In the rumen, fermentation of glucose will produce VFA for the host animal to use.

107
Q

Gluconeogenesis

A

synthesis of new glucose from starting materials (precursors) that are not carbohydrates

108
Q

ATP

A

adenosine triphosphate

109
Q

Amylase

A

an enzyme taht catalyzes hydrolysis of the alpha(1–>4) glycosidic bond (ether linkage) of amylose (starch)

110
Q

Debranching enzyme

A

an enzyme that catalyzes hydrolysis of the alpha(1–>6) glycosidic bond (ether linkage) of amylopectin and glycogen

111
Q

Enterocyte

A

absorptive cell of the small intestine

112
Q

Active transport

A

the transport or movement of digested nutrients into the enterocyte by methods that require the energy supplied by ATP. Active transport also a means of transporting materials across membranes of other tissues in the body

113
Q

Sodium-glucose co-transporter

A

A transport system in which glucose is transported into the cell along with sodium ion, which is then transported out of the cell using the energy of ATP hydrolysis (active transport)

114
Q

Hepatic portal vein

A

The large blood vessel that transports nutrients from the gasto-intestinal tract to the liver

115
Q

Energy nutrient

A

a nutrient that is used (oxidized) for the purpose of generating ATP

116
Q

Insulin

A

A hormone primarily secreted from the beta-cells of the pancreas in response to digestion and absorption of glucose. Insulin stimulates cells of many tissues to transport glucose from the blood (glucose that originated from the diet) into the cells of the body

117
Q

Glucose transporter

A

specialized proteins found in the membranes of many tissue cells that are used for transport of glucose across the cell membrane

118
Q

Glycolysis

A

directly translate as “breaking glucose”. Biochemically glucose is modified and split into two three-carbon molecules, each one ultimately becoming the molecule, pyruvate.

119
Q

Cytosolic

A

in the cytosol of the cell. The cytosol is the area within the cell and between/ surrounding the organelles, as well as not part of the nucleus

120
Q

Anaerobic

A

directly translated as “without air”. Describes metabolism in which oxygen is not directly needed

121
Q

Aerobic

A

requirig air. Describes metabolism in which oxygen will be directly needed

122
Q

Lactate

A

a three-carbon molecule that originates from glucose and that occurs after glycolysis in an anaerobic cell type. Lactate is produced from pyruvate so that NAD+ can be regenerated

123
Q

Pyruvate

A

a three-carbon molecule that is the end product of glycolysis regardless of the cell type (aerobic and anaerobic); if anaerbic, pyruvate is converted to lactate

124
Q

Mitochondrea

A

the cell organelle where oxidative metabolism takes place

125
Q

Acetyl-CoA

A

acetate that has coenzyme-A bonded to the caboxyl end via a thioester. Acetyl-coA is the molecule that represents the starting point for ATP generation if energy is needed, as well as for fatty acid synthesis if nutrient supply is excessive. If energy is needed, glucose, fatty acids, and some amino acids are broken down by metabolic processes (catabolism) that result in their conversion to acetyl-CoA, which then is oxidized in the mitochondria for production of ATP. If the glucose and certain amino acids are in nutrient excess, the acetyl-CoA, which then is oxidized in the mitochondria for production of ATP. If the glucose and certain AA are in nutrient excess, the acetyl-CoA is diverted to fatty acid production so that the nutrient energy supply can be stored

126
Q

Glucose-6-phoshpate

A

product of the first reaction of glycolysis

127
Q

hexokinase

A

the enzyme that catalyzesconversion of glucose to glucose-6-phosphate. Hexokinase aslo is the rate-limiting enzyme of glycolysis

128
Q

ATP hydrolysis

A

hydrolysis of a phosphate from ATP, which results in ADP and phosphate. ATP hydrolysis produces energy that is used to drive other biochemical reactions

129
Q

Kinase

A

an enzyme that catalyzestransfer of a phosphate either to ADP to produce ATP or from ATP to another molecule. Kinase is a class of enzyme, and there are numerous kinases specific to certain reactions

130
Q

ADP

A

adenosin diphosphate

131
Q

Rate-limiting enzyme

A

the enzyme that catalyzes the reaction that determines the rate at which subsequent reactions occur. THis is usually relevant to a series or sequence of reactions that produce specific end products, for example, glycolysis. Also, the rate-limiting enzyme is the primary enzyme that is regulated by inhibitors or activators

132
Q

Fructose-6-phosphate

A

the product of the second reaction in glycolysis and which glucose-6-phosphate is converted

133
Q

Isomerization

A

conversion of a molecule to another of the same formula, for example, glucose-6-phosphate to fructose-6-phosphate

134
Q

Glucose-phosphate isomerase

A

the enzyme that catalyzes isomerization of glucose-6-phosphate to fructose-6-phosphate

135
Q

Fructose-1,6-bisphosphate

A

fructose with two phosphates. Each phosphate is bonded to a different part of Fructose (carbons 1 and 6)

136
Q

phosphofructokinase

A

the kinase enzyme that catalyzes transfer of a phosphate to carbon number 1 of fructose-6-phosphate

137
Q

Committed step

A

the step or reaction of a metabolic pathway in which the product will only go to completion of specific route. For example, some reaction sequences have points in which a product can go in different directions because more than one possible reaction sequence occurs. However, once a product in the middle of a reaction sequence reaches a point of “no return” or deviation to another end product, it becomes committed. once glucose is converted to fructose-1,6-bisphosphate, it can only proceed to convert to pyruvate

138
Q

glyceraldehyde-3-phosphate

A

the product of the fourth reaction of glycolysis in which the six-carbon fructose-1,6-bisphophate is split into two three-carbon molecules; one is glyceraldehydes-3-phosphate

139
Q

dihydroxyacetone phosphate

A

the other three-carbon molecule that is produced when fructose-1,6-bisphosphate is split

140
Q

Aldolase

A

The enzyme that catalyzes the splitting of fructose-1,6-bisphosphate into the two 3-carbon molecules

141
Q

triose phosphate isomerase

A

the enzyme that catalyzes conversion (isomerization) of dihydroxyacetone phosphate into glyceraldehyde-3-phosphate

142
Q

Nicotinamide adenine dinucleotide (NAD)

A

an enzyme cofactor that is involved with oxidation and reduction reactions. NAD can be reduced to form NADH; the NADH can be oxidized to form NAD

143
Q

Reduction

A

The addition of hydrgen ion to a molecule

144
Q

Oxidation

A

The removal of hydrogen ions from a molecule

145
Q

1,3- bisphosphoglycerate

A

the product of phosphorylation of glyceraldehyde-3 phosphate in the sixth reaction of glycolysis

146
Q

L-lactate

A

refers to the lactate isomer that is produced in the rumen and that is metabolized by the liver and heart

147
Q

D-lactate

A

the lactate isomer that is also produced in the rume but that is not metabolized fast enough and tends to be excreted in the urine

148
Q

Acidosis

A

the condition characterized by low blood pH and which is caused primarily by a buildup of lactic acid (usally the D-lactate isomer)

149
Q

Mitochondria

A

the organelle where pyruvate and fatty acid oxidation occur

150
Q

Pyruvate dehyrogenase compled (PDH)

A

the enzyme system located in the mitochodrial membrane taht catalyzes conversion of pyruvate to acetyl-CoA

151
Q

Flavin Adenine Dinucleotide FAD

A

an enzyme cofactor that is involved in oxidation and reduction reactions in cellular metabolism much like NAD/NADH. The reduced form of FAD is FADH2

152
Q

Tricarboxylic Acid Cycle TCA

A

the metabolic pathway that completes the oxidation of acetyl-CoA, and which occurs in the mitochondria. This metabolic pathway is called a cyle beause the last product produced is the starting material for the next turn of the reaction pathway. The TCA cycle also is called the Krebs cycle in honor of Hans Krebs and the Citric Acid cyle because the first product of the reaction pathway is citric acid. Overall, the TCA cycle complete the oxidation of glucose and fatty acids

153
Q

Oxaloacetate

A

the final product of the TCA cycle, it condenses with Acetyl-CoA to form the first product of the cycle, citrate

154
Q

Citrate

A

the first product of the TCA cycle, citrate is a molecule with three caboxylic acid groups, hence the name tricaboxylic acid

155
Q

Isocitrate

A

Conversion product of citrate early in the TCA cycle

156
Q

Oxalosuccinate

A

Conversion product of isocitrate in the TCA cycle

157
Q

alpha-ketoglutarate

A

conversion product of oxalosuccinate in the TCA cycle

158
Q

Succinyl-CoA

A

conversio product of alpha-ketoglutarate in the TCA cycle

159
Q

guanine diphosphate GDP

A

a nucleotide diphosphate that will be converted to GTP during the TCA cycle. The phosphate of GTP will immediately be transferred to ADP producing ATP and regenerating GTP

160
Q

Succinate

A

the conversion product of succinyl-CoA in the TCA cycle. This reaction also is associated with phosphorylation of GDP

161
Q

Malate

A

conversion product of succinate in the TCA cycle

162
Q

Fumerate

A

conversion product of malate in the TCA cycle

163
Q

Energy potential

A

This refers to the energy harbored in ATP, as well as NADH and FADH2 that will be used to power cellular functions in the animal