Biochemistry Flashcards

Question

What kind of amino acid is glutamine?

Answer 1

Polar, non-aromatic

Answer 2

Polar, non-aromatic

Answer 3

Negatively charged (acidic)

Answer 4

Negatively charged (acidic)

Answer 5

Positively charged (basic)

Answer 6

Positively charged (basic)

Answer 7

Positively charged (basic)

Answer 8

CH - (CH3)2

Answer 9

CH2 - CH - (CH3)2

Answer 10

CH - [CH3, CH2 - CH3]

Answer 11

CH2 - CH2 - S - CH3

Answer 12

CH2 - double ring system with N

Answer 13

CH2 - benzene ring

Answer 14

CH2 - Phenyl

Answer 15

C - [H, OH, CH3]

Answer 16

CH2 - C - [NH2, O]

Answer 17

CH2 - CH2 - C - [NH2, O]

Answer 18

CH2 - COO-

Answer 19

CH2 - CH2 - COO-

Answer 20

(CH2)4 - NH3+

Answer 21

(CH2)3 - NH - C - [NH, NH3+]

Answer 22

CH2 - imidazole ring

Answer 23

Ala, A, non polar, non-aromatic

Answer 24

Arg, R, basic

Answer 25

Asn, N, polar, non-aromatic

Answer 26

Asp, D, acidic

Answer 27

Cys, C, polar, non-aromatic

Answer 28

Glu, E, acidic

Answer 29

Gln, Q, polar, non-aromatic

Answer 30

Gly, G, non polar, non-aromatic

Answer 31

His, H, basic

Answer 32

Ile, I, nonpolar, non-aromatic

Answer 33

Leu, L, nonpolar, non-aromatic

Answer 34

Lys, K, basic

Answer 35

Met, M, nonpolar, non-aromatic

Answer 36

Phe, F, nonpolar, aromatic

Answer 37

Pro, P, nonpolar, non-aromatic

Answer 38

Ser, S, polar, non-aromatic

Answer 39

Thr, T, polar, non-aromatic

Answer 40

Trp, W, nonpolar, aromatic

Answer 41

Tyr, Y, polar, aromatic

Answer 42

Val, V, nonpolar, non-aromatic

Answer 43

Makes up peptide chains (i.e. proteins)

Answer 44

Two amino acids joined by a peptide bond

Answer 45

Three amino acids joined by peptide bonds

Answer 46

Less than 20 amino acids joined by peptide bonds

Answer 47

More than 20 amino acids joined by peptide bonds

Answer 48

Linear amino acid sequence

Answer 49

Local structure determined by nearby amino acids

Answer 50

Alpha-helices and beta-pleated sheets

Answer 51

Peptide (amide) bonds

Answer 52

Hydrogen bonds between amino groups and nonadjacent carboxyl groups

Answer 53

Its rigid structure causes it to introduce kinks in alpha-helices, or create turns in beta-pleated sheets

Answer 54

Protein folding (three-dimensional shape of protein)

Answer 55

Interaction between separate subunits of a multisubunit protein

Answer 56

Hydrophobic interactions, acid-base/salt bridges, disulfide links

Answer 57

Hydrogen bonds, van der Waals forces, ionic bonds and covalent bonds

Answer 58

Hydrogen bonds, van der Waals forces, ionic bonds and covalent bonds

Answer 59

Heat increases the average kinetic energy, thereby distrusting hydrophobic interactions

Answer 60

Solutes disrupt elements of secondary, tertiary and quaternary structures

Answer 61

= (pKa, NH3+ group + pKa, COOH group) / 2

Answer 62

= (pKa, R group + pKa, COOH group) / 2

Answer 63

= (pKa, R group + pKa, NH3+ group) / 2

Answer 64

Determine the chemistry and function of that amino acid

Answer 65

It is fully protonated

Answer 66

The amino acid is neutral (zwitterion)

Answer 67

It is fully deprotonated

Answer 68

Flat at pKa values and vertical in pI values

Answer 69

Through a condensation or dehydration reaction, releasing one molecule of water The nucleophile (amino group) of one amino acid attacks the electrophile (carboxyl group) of another amino acid

Answer 70

Amino group

Answer 71

Carbonyl carbon of the carboxyl group

Answer 72

Because of resonance

Answer 73

Hydrolysis reaction

Answer 74

Clockwise coils around a central axis

Answer 75

Rippled strands that can be parallel or antiparallel

Answer 76

Yes because of its rigid structure

Answer 77

Push hydrophobic R groups to the interior of a protein, which increases entropy of the surrounding water molecules and creates negative Gibbs free energy

Answer 78

Increase in entropy of the surrounding water and negative Gibbs free energy

Answer 79

When two cysteine molecules are oxidized and create a covalent bond to form cystine

Answer 80

Proteins with covalently attached molecules

Answer 81

Tightly bound cofactors or coenzymes that are necessary for enzyme function The molecule attached to a conjugated protein Can be metal ion, vitamin, lipid, carbohydrate or nucleic acid

Answer 82

Loss of three-dimensional protein structure

Answer 83

Threonine and isoleucine

Answer 84

Directing protein to a particular organelle, directing protein to the cell membrane and adding a cofactor needed to protein activity

Answer 85

Improve the environment in which a particular reaction takes place, which lowers its activation energy They are regenerated at the end of the reaction to their original form They can form transient covalent bonds with substrates They can act as electron donors or receptors to allow the reaction to proceed

Answer 86

Enzymes are specific for certain kinds of compounds and perform certain kinds of reactions

Answer 87

Ligase, isomerase, lyase, hydrolase, oxidoreductase and transferase

Answer 88

Addition or synthesis reactions, generally between large molecules (often of the same type); often require ATP

Answer 89

Rearrangement of bonds within a compound Catalyze the interconversion of isomers, including both constitutional isomers and stereoisomers

Answer 90

Cleavage of a single molecule into two products, or synthesis of small organic molecules Does not use water or transfer electrons The opposite of synthesis Often form cyclic compounds or double bonds in products

Answer 91

Breaking of a compound into two molecules using the addition of water

Answer 92

Oxidation-reduction reactions (transferring electrons)

Answer 93

Movement of a functional group from one molecule to another

Answer 94

Enzymes only affect the kinetics of a reaction, by lowering the activation energy (i.e. lowering the transition state energy). Enzymes do not affect the thermodynamics of a reaction since they do not change delta G, delta H, the equilibrium constant, the equilibrium position or the concentrations of reactants and products.

Answer 95

Reduce the activation energy of a reaction, thus speeding up the reaction They are not used up in the course of the reaction

Answer 96

Active site of enzyme fits exactly around substrate No alterations to tertiary or quaternary structure of enzyme Less accurate model

Answer 97

Active site of enzyme molds itself around substrate only when substrate is present Tertiary and quaternary structure is modified for enzyme function More accurate model

Answer 98

Inorganic (minerals) activators of enzymes | Induce conformational change in the enzyme to promote its activity

Answer 99

Organic (vitamins) activators of enzymes | Induce conformational change in the enzyme to promote its activity

Answer 100

When the substrate concentration is low, an increase in substrate concentration causes a proportional increase in enzyme activity When the substrate concentration is high and the enzyme is saturated, increasing substrate concentration will have no effect on enzyme activity since v max has already been attained

Answer 101

Increasing enzyme concentration will always increase v max, regardless of the starting concentration of enzyme

Answer 102

v vs [S] | Hyperbolic curve for monoatomic enzymes

Answer 103

1/v vs 1/[S] | Linear plot

Answer 104

A measure of an enzyme's affinity for its substrate | The substrate concentration at which an enzyme is functioning at half of its maximal velocity

Answer 105

Decrease in an enzyme's affinity for its substrate

Answer 106

The interactions between subunits in a multi-subunit enzyme or protein The binding of a substrate to one subunit induces a change in the other subunits from the T(tense) state to the R (relaxed) state, which encourages binding of substrate to the other subunits The unbinding of a substrate from one subunit indices a change from R to T in the remaining subunits, promoting unbinding of substrate from the remaining subunits

Answer 107

As temperature increases, enzyme activity generally increases (doubling approximately every 10 C) Above body temperature, however, enzyme activity quickly drops off as the enzyme denatures

Answer 108

Enzymes are maximally active within a small pH range Outside of the range, enzyme activity drops quickly with changes in pH as the ionization of the active site changes and the protein is denatured

Answer 109

Changes in salinity can disrupt bonds within an enzyme, causing disruption of tertiary and quaternary structure, which leads to loss of enzyme function

Answer 110

98.6 F = 37 C = 310 K

Answer 111

The product of an enzymatic pathway turning off enzymes further back in that same pathway Helps maintain homeostasis: as product levels rise, the pathway creating that product is appropriately down-regulated

Answer 112

Competitive, noncompetitive, mixed and uncompetitive

Answer 113

The prolonged or permanent inactivation of an enzyme, such that is cannot be easily renatured to gain function New enzyme molecules must be synthesized for the reaction to occur again

Answer 114

Allosteric activation | Allosteric inhibition

Answer 115

Phosphorylation | Glycosylation

Answer 116

It is critical that certain enzymes (like the digestive enzymes of the pancreas) remain inactive until arriving at their target site

Answer 117

Precursors of an active enzyme They are secreted in an inactive form and are activated by cleavage

Answer 118

E + S ES --(K3)--> E + P

Answer 119

v = ( v max [S]) / (Km + [S])

Answer 120

The opposite of lyases

Answer 121

Release energy | delta G is negative

Answer 122

Exergonic reaction

Answer 123

Yes | They provide a favorable micro-environment or bonding with substrate molecules

Answer 124

The site of catalysis in an enzyme

Answer 125

As substrate concentration increases, the reaction rate does as well until a maximum value is reached

Answer 126

Sigmoidal because of the change in activity with substate binding

Answer 127

In the lab

Answer 128

In the body

Answer 129

The ability to replace the inhibitor with a compound greater affinity or to remove it using mild laboratory treatment

Answer 130

Results when the inhibitor is similar to the substrate and binds at the active site

Answer 131

Adding more substrate

Answer 132

Results when the inhibitor binds with equal affinity to the enzyme (at an allosteric site) and the enzyme-substrate complex

Answer 133

Results when the inhibitor binds with unequal affinity to the enzyme (at an allosteric site) and the enzyme-substrate complex

Answer 134

Increases if the inhibitor prefers to bind to the enzyme at an allosteric site Decreases if the inhibitor prefers to bind to the enzyme-substrate complex

Answer 135

Results when the inhibitor binds only with the enzyme-substrate complex

Answer 136

Activators bind to the allosteric site of an enzyme, increasing enzyme affinity to substrate

Answer 137

Inhibitors bind to the allosteric site of an enzyme, decreasing enzyme affinity to substrate

Answer 138

Covalent modification of an enzyme with phosphate Can alter the activity or selectivity of an enzyme

Answer 139

Covalent modification of an enzyme with carbohydrate Can alter the activity or selectivity of an enzyme

Answer 140

An enzyme devoid of its necessary cofactor and is catalytically inactive

Answer 141

The three-dimensional shape of the active site

Answer 142

Fibrous Have repeating domains Function in cellular motility

Answer 143

Have one or more heads capable of force generation through a conformational change Have catalytic activity, acting as ATPases to power movement

Answer 144

If the binding protein is present in sufficiently high quantities relative to the substrate, nearly all substrate will be bound despite a low affinity

Answer 145

Allow cells to bind to other cells or surfaces | Cadherin, integrin and selectin

Answer 146

Two cells of the same or similar type using calcium

Answer 147

One cell to proteins in the extracellular matrix

Answer 148

One cell to carbohydrates, usually on the surface of other cells

Answer 149

Antigen-antibody interactions can result in neutralization of the pathogen or toxin, opsonization (marking) of the antigen for destruction, or creation of insoluble antigen-antibody complexes that can be phagocytize and digested by macrophages (agglutination).

Answer 150

A protein or RNA molecule with catalytic activity

Answer 151

``` Participate in cell signaling through extracellular ligand binding and initiation of second messenger cascades Autoactivity Enzymatic activity Extracellular domain Transmembrane domain Ligand binding ```

Answer 152

``` Have membrane-bound protein associated with a trimetric G protein Initiate second messenger systems Two-protein complex Dissociation upon activation Extracellular domain Transmembrane domain Ligand binding ```

Answer 153

Ungated channels

Answer 154

Transport kinetics display both Km and v max values. They also can be cooperative, like some binding proteins. However, transporters do not have analogous Keq values for reactions because there is no catalysis.

Answer 155

Isoelectric focusing and ion-exchange chromatography can separate proteins based on charge

Answer 156

Native PAGE allows a complete protein to be recovered after analysis; it also more accurately determines the relative globular size of proteins. SDS-PAGE can be used to eliminate conflation from mass-to-charge ratios.

Answer 157

The protein of interest may not elute from the column because its affinity is too high The protein may be permanently bound to the free receptor in the eluent

Answer 158

The largest molecules elute first since the size-exclusion chromatography trap smaller particles, retaining them in the column

Answer 159

Separate proteins by charge | The protein migrates towards an electrode until pH = pI of the protein

Answer 160

Separate proteins by charge

Answer 161

By the protein's isoelectric point (pI)

Answer 162

Protein isolation is generally only the first step in an analysis. The protein identity must be confirmed by amino acid analysis or activity. With unknown proteins, classification of their features is generally desired.

Answer 163

Contamination of the sample with detergent or SDS could yield an artificially increased protein level, leading to lower activity than expected (because the protein concentration was calculated as higher than its actual value). Alternatively, the enzyme could have been denatured during isolation and analysis.

Answer 164

Amino (N-) terminus

Answer 165

Compose the cytoskeleton, anchoring proteins and must of the extracellular matrix Fibrous

Answer 166

Collagen, elastin, keratin, actin and tubulin

Answer 167

Muscle contractions, vesicle movement within cells, cell motility

Answer 168

Myosin, kinesin and dynein

Answer 169

Bind a specific substrate, either to sequester it in the body or hold its concentration at steady state

Answer 170

Calcium-dependent glycoproteins that hold similar cells together

Answer 171

Have two membrane-spanning chains and permit cells to adhere to proteins in the extracellular matrix. Some also have signaling capabilities

Answer 172

Allow cells to adhere to carbohydrates on the surfaces of other cells and are most commonly used in the immune system

Answer 173

Used by the immune system to target a specific antigen, which may be a protein on the surface of a pathogen (invading organism) or a toxin

Answer 174

Contain a constant region and variable region; the variable region is responsible for antigen binding Two identical heavy chains and two identical light chains form a single antibody; they are held together by disulfide linkages and non covalent interactions

Answer 175

By disulfide linkages and non-covalent interactions

Answer 176

Used to regulate ion flow into or out of the cells

Answer 177

Ungated, voltage-gated and ligand-gated

Answer 178

Are always open

Answer 179

Open within a range of membrane potentials

Answer 180

Open in the presence of a specific binding substance, usually a hormone or neurotransmitter

Answer 181

Ligand binding engages the G protein --> GDP is replaced with GTP --> The alpha subunit dissociates from the beta and gamma subunits --> The activated alpha subunit alters the activity of adenylate cyclase or phospholipase C --> GTP is dephosphorylated to GDP --> The alpha subunit rebinds to the beta and gamma subunits

Answer 182

Uses a Gell matrix to observe the migration of proteins in response to an electric field

Answer 183

Maintains the protein's shape, but results are difficult to compare because the mass-to-charge ration differs for each protein

Answer 184

Denatures the proteins and masks the native charge so that comparison of size is more accurate, but the functional protein cannot be recaptured from the gel

Answer 185

Separates protein mixtures on the basis of their affinity for a stationary phase or a mobile phase

Answer 186

Uses beads of a polar compound, like silica or alumina (stationary phase), which a non polar solvent (mobile phase)

Answer 187

Uses a charged column and a variably saline eluent

Answer 188

Relies on porous beads | Larger molecules elute first because they are not trapped in the small pores

Answer 189

Uses a bound receptor or ligand and an eluent with free ligand or a receptor for the protein of interest

Answer 190

X-ray crystallography (after the protein has been isolated) | NMR can also be used

Answer 191

Simple hydrolysis

Answer 192

Sequential degradation

Answer 193

Edman degradation

Answer 194

Following the process of a known reaction and color change

Answer 195

Colorimetrically (either by UV spectroscopy or color change in a reaction) Bradford protein assay test BCA assay Lowry reagent assay

Answer 196

Uses color change from brown-green to blue

Answer 197

The principle of this method is that proteins can reduce Cu+2 to Cu+1 in an alkaline solution (the biuret reaction) and result in a purple color formation by bicinchoninic acid.

Answer 198

The Lowry protein assay uses copper, which bonds with the peptide bonds in proteins under alkaline conditions. This forms a monovalent copper ion which can then react with the Folin reagent, which in turn can be reduced into a blue colored substance. This blue color can be measured using a spectrophotometer to determine the concentration of blue in the sample. Thus, the concentration of protein can be determined.

Answer 199

It stabilizes proteins to give them uniformly negative charges, so the separation is based purely on size

Answer 200

Keratin, elastin and collagen

Answer 201

Tubulin and actin

Answer 202

Motor protein

Answer 203

Ungated channels

Answer 204

Ligand-gated and voltage-gated channels

Answer 205

Isoelectric focusing uses gel with a pH gradient that encourages a variable charge

Answer 206

Proteins contain aromatic groups in certain amino acids

Answer 207

Selectivity

Answer 208

D-allose, D-altrose, D-glucose, D-mannose, D-gulose, D-idose, D-galactose and D-talose

Answer 209

D-allose, D-mannose and D-galactose

Answer 210

``` OH at C1: pointing down OH at C2: pointing down OH at C3: pointing up OH at C4: pointing down CH2OH at C5: pointing up ```

Answer 211

All the hydroxyl groups are in the axial position

Answer 212

Esterification is the reaction by which a hydroxyl group reacts with either a carboxylic acid or a carboxylic acid derivative to form an ester. Glycoside formation refers to the reaction between an alcohol and a hemiacetal (or hemiketal) group on a sugar to yield an alkoxy group.

Answer 213

Oxidized; because aerobic metabolism requires reduced forms of electron carriers to facilitate processes such as oxidative phosphorylation. Because carbohydrates are a primary energy source, they are oxidized.

Answer 214

Amylopectin is more soluble in solution than amylose because of its branched structure. The highly branched structure of amylopectin decreases intermolecular bonding between polysaccharide polymers and increases interaction with the surrounding solution.

Answer 215

Glycogen has a higher rate of enzymatic branch cleavage because it contains significantly more branching than amylopectin.

Answer 216

= 2^n, where n = the number of chiral carbons

Answer 217

By their number of carbon atoms and functional groups

Answer 218

Three-carbon sugars

Answer 219

Four-carbon sugars

Answer 220

Sugars with aldehydes as their most oxidized group

Answer 221

Sugars with ketones as their most oxidized group

Answer 222

D- and L-forms of glyceraldehydes

Answer 223

Sugars with the highest-numbered chiral carbon with the -OH group on the right in a Fischer projection

Answer 224

Sugars with the highest-numbered chiral carbon with the -OH group on the left in a Fischer projection

Answer 225

D- and L-forms

Answer 226

"Nonsuperimposable configurations of molecules with similar connectivity Differ in at least one, but not all, chiral carbons"

Answer 227

Epimers and anomers

Answer 228

A subtype of diastereomerts that differ at exactly one chiral carbon

Answer 229

A subtype of diastereomers that differ at the anomeric carbon

Answer 230

Describes the ring formation of carbohydrates from their straight-chain forms

Answer 231

The new chiral center formed in ring closure; it was the carbon containing the carbonyl in the straight-chain form

Answer 232

Have the -OH on the anomeric carbon trans to the free -CH2OH group

Answer 233

Have the -OH on the anomeric carbon cis to the free -CH2OH group

Answer 234

Provide a good way to represent three-dimensional structures

Answer 235

"Cyclic compounds shift from one anomeric form to another with the straight-chain form as an intermediate The hemiacetal ring of the sugar will break open spontaneously and then re-form. When the ring is broken, bond rotation occurs between C-1 and C-2 to produce either the alpha- or beta- anomer"

Answer 236

Single carbohydrate units, with glucose as the most commonly observed monomer

Answer 237

Oxidation-reaction, esterification and glycoside formation

Answer 238

Aldonic acids

Answer 239

Sugars that are oxidized and act as reducing agents

Answer 240

Tollen’s reagent or Benedict’s reagent

Answer 241

Sugars with a -H replacing an -OH group

Answer 242

Sugars can react with carboxylic acids and their derivatives, forming esters

Answer 243

"Similar to esterification | Phosphate ester is formed by transferring a phosphate group from ATP onto a sugar"

Answer 244

The basis for building complex carbohydrates and requires the anomeric carbon to link to another sugar

Answer 245

Form as result of glycosidic bonding between two monosaccharide subunits

Answer 246

By repeated monosaccharide or polysaccharide glycosidic bonding

Answer 247

Sucrose, lactose and maltose

Answer 248

Glucose-alpha-1,2-fructose

Answer 249

Galactose-beta-1,4-glucose

Answer 250

Glucose-alpha-1,4-glucose

Answer 251

Cellulose, starches and glycogen

Answer 252

The main structural component for plant cell walls and is a main source of fiber in the human diet

Answer 253

Amylose and amylopectin

Answer 254

Function as a main energy storage form for plants

Answer 255

Functions as a main energy storage form for animals

Answer 256

Sugar that has one aldehyde group and six carbons, e.g. glucose

Answer 257

The addition of a sugar to another compound

Answer 258

A rearrangement of bonds to undergo keto-enol shifts

Answer 259

Refers to ring closure of a monosaccharide, creating an anomeric carbon

Answer 260

The hemiacetal is converted to an acetal via replacement of the anomeric hydroxyl group with an an alkoxy group, the result is a type of acetal known as a glycoside

Answer 261

Cleaves amylose at the nonreducing end of the polymer to yield maltose

Answer 262

Cleaves amylose anywhere along the chain to yield short polysaccharides, maltose and glucose

Answer 263

Removes oligosaccharides from a branch in glycogen or starches

Answer 264

Yields glucose 1-phosphate (GMP)

Answer 265

1. Draw out the Haworth conformation 2. All the groups on the right in the Fischer projection will go on the bottom of the Haworth projection 3. All the groups on the left in the Fischer projection will go on the top of the Haworth projection 4. Draw out the chair structure, with the oxygen in the back right corner 5. Label the carbons in the ring 1 through 5 from the oxygen and moving clockwise around the ring 6. Draw in the lines for all the axial substituents, alternating above and below the ring 7. What was pointing down in the Haworth projection, will also point down for the chair conformation 8. What was pointing up in the Haworth projection, will also point up for the chair conformation

Answer 266

Glycogen and amylopectin

Answer 267

Alpha-1,4 and alpha 1,6

Answer 268

Alpha-1,4 and alpha 1,6

Answer 269

Because cellobiose contain beta-glycosidic linkages and humans do not have the enzymes to cleave them

Answer 270

Hemiacetals and hemiketals

Answer 271

The fatty acid tails form the bulk of the phospholipid bilayer and play a predominantly structural role

Answer 272

"The polar head group determines the function of the membrane lipid due to its constant exposure to the exterior environment of the phospholipid bilayer The degree of unsaturation of fatty acid tails can also play a small role in function"

Answer 273

The difference is the bond between the sphingosine backbone and the head group. When this is a phosphodiester bond, it’s a phospholipid. Nonphospholipid sphingolipids include glycolipids, which contain a glycosidic linkage to a sugar.

Answer 274

Sphingomyelin, glycosphingolipid and ganglioside

Answer 275

In a nonpolar solvent, we would see the opposite of what happens in a polar solvent like water: the hydrophilic, polar part of the molecules would be sequestered inside, while the nonpolar, hydrophobic part of the molecules would be found on the exterior and exposed to the solvent

Answer 276

Phosphodiester bond between the sphingosine backbone and the head group

Answer 277

Glycosidic linkage between sphingosine backbone and a sugar

Answer 278

Phospholipid

Answer 279

Glycolipid

Answer 280

Glycolipid

Answer 281

Phosphatidylethanolamine / phosphatidylcholine

Answer 282

Sugars (mono- or polysaccharides)

Answer 283

Oligosaccharides and N-acetylneuraminic acid (NANA)

Answer 284

``` "A steroid is defined by its structure: it includes 3 cyclohexane rings and one cyclopentane ring A steroid hormone is a molecule within this class that also functions as a hormone, meaning that it travels in the bloodstream, is active at low concentrations, has high-affinity reception and affects gene expression and metabolism." ```

Answer 285

Prostaglandins regulate the synthesis of cAMP, which is involved in many pathways, including those that drive pain and inflammation

Answer 286

Vitamin A (carotene), vitamin D (cholecalciferol), vitamin E (tocopherols) and vitamin K (phylloquinone and menaquinones)

Answer 287

Made of 2 isoprene units

Answer 288

"Metabolized to retinal for vision | Metabolized to retinoid acid for gene expression in epithelial development"

Answer 289

Metabolized to calcitriol in the kidneys to regulate calcium and phosphate homeostasis in the intestines (increasing calcium and phosphate absorption) and promoting bone formation

Answer 290

Metabolized to biological antioxidants, using their aromatic rings to destroy free radicals, preventing oxidative damage

Answer 291

"Important for the formation of prothrombin, a clotting factor Performs posttranslational modification to a number of proteins, creating calcium-binding sites"

Answer 292

The human body stores energy as glycogen and triacylglycerols

Answer 293

Triacylglycerols are preferred because their carbons are more reduced, resulting in a larger amount of energy yield per unit weight. In addition, due to their hydrophobic nature, triacylglycerols do no need to carry extra weight from hydration.

Answer 294

One glycerol attached to three fatty acids by ester bonds The carbon atoms in lipids are more reduced than those in carbohydrates, giving them twice as pure energy per gram during oxidation Hydrophobic, so they are not hydrated by body water and do not carry additional water weight

Answer 295

The ester bonds of triacylglycerols (triglycerides) are broken to form a glycerol molecule and the salts of fatty acids (soap)

Answer 296

Soap appears to dissolve in water because amphipathic free fatty acid salts form micelles, with hydrophobic fatty acid tails towards the center and carboxylate groups facing outward towards the water. Fat-soluble particles can then dissolve inside micelles in the soap-water solution and wash away. Water-soluble compounds can freely dissolve in the water.

Answer 297

Energy storage

Answer 298

"Amphipathic Form the bilateral of biological membrane Contain a hydrophilic (polar) head group and hydrophobic (nonpolar) tails The head group is attacked by a phosphodiester linkage"

Answer 299

Phospholipids that contain a glycerol backbone

Answer 300

Contain a sphingosine or sphenoid backbone Can have a phosphodiester bond (phospholipids) or glycosidic bonds (glycolipids) Used in ABO blood typing

Answer 301

Sphingolipids that are phospholipids because they have a phosphodiester bond

Answer 302

``` "A major class of sphingophospholipids and contain a phosphatidylcholine or phosphatidylethanolamine head group A major component of the myelin sheath" ```

Answer 303

Attached to sugar moieties instead of a phosphate group

Answer 304

Have one sugar connected to a sphingosine

Answer 305

Have two or more sugars connected to a sphingosine

Answer 306

Contain oligosaccharides with at least one terminal N-acetylneuraminic acid (NANA) also called sialic acid

Answer 307

Contain long-chain fatty acids esterified to long-chain alcohols Used as protection against evaporation (dehydration) and parasites in plants and animals Generally have melting points above room temperature

Answer 308

Odiferous steroid precursors made from isoprene

Answer 309

A five-carbon molecule

Answer 310

"One terpene unit | Contains two isoprene units"

Answer 311

"Derived from terpenes via oxygenation or backbone rearrangement They have similar odorous characteristics"

Answer 312

Contain three cyclohexane rings and one cyclopentane ring

Answer 313

Have high-affinity receptors, work at low concentrations, travel in the bloodstream from endocrine glands and affect gene expression and metabolism by binding to DNA as part of the hormone-receptor complex, but not by itself

Answer 314

A steroid important to membrane fluidity and stability; it serves as a precursor to a host of other molecules like steroid hormones

Answer 315

Autocrine and paracrine signals molecules that regulate cAMP levels Have powerful effects on smooth muscle contraction, body temperature, the sleep-wake cycle, fever, inflammation and pain Their synthesis is inhibited by NSAIDs

Answer 316

Vitamin D (cholecalciferol) deficiency

Answer 317

Triacylglycerols (triglycerides)

Answer 318

Animal cells specifically used for storage of large triacylglycerol deposits

Answer 319

Unesterified fatty acids that travel in the bloodstream

Answer 320

Salts of free fatty acids | Acts as surfactants, forming micelles

Answer 321

Through saponification

Answer 322

The ester hydrolysis of triacylglycerols using a strong base, like NaOH or KOH

Answer 323

Can dissolve a lipid-soluble molecule in its fatty acid core Washes away with water because of its shell of carboxylate head groups Collection of lipids with their hydrophobic ends oriented towards the center and their charged ends orientated towards the aqueous environment Collect lipids within their hydrophobic centers

Answer 324

Cerebroside, globoside and ganglioside

Answer 325

Phosphodiester bond

Answer 326

Describes the number of double or triple bonds in a fatty acid tail Determines membrane fluidity

Answer 327

Only have single bonds

Answer 328

Contains a five-carbon sugar (pentose) and a nitrogenous base

Answer 329

Composed of a nucleoside plus one to three phosphate groups

Answer 330

A pairs with T in DNA, using 2 hydrogen bonds A pairs with U in RNA, using 2 hydrogen bonds C pairs with G in DNA and RNA, using 3 hydrogen bonds The backbone is composed of alternating sugar and phosphate groups, and is always read 5' to 3' The two strands are antiparallel in polarity and are wound into a double helix

Answer 331

DNA contains deoxyribose, while RNA contains ribose DNA contains thymine, while RNA contains uracil DNA is double-stranded, while RNS is single-stranded

Answer 332

The aromaticity of nucleic acids makes these compounds very stable and interactive Stability is important for storing genetic information and avoiding spontaneous mutations

Answer 333

H1, H2A, H2B, H3, H4

Answer 334

Uncondensed (not dense)

Answer 335

High GC-content increases hydrogen bonding, making the association between DNA strands very strong at telomeres and centromeres

Answer 336

Unwinds DNA double helix

Answer 337

Prevents reannealing of DNA double helix during replication

Answer 338

Places ~10-nucleotide RNS primer to begin DNA replication

Answer 339

Prokaryotes

Answer 340

Adds nucleotides to growing daughter strand

Answer 341

Eukaryotes

Answer 342

Adds nucleotides to growing daughter strand

Answer 343

Prokaryotes

Answer 344

Fills in gaps left behind after RNS primer excision

Answer 345

Eukaryotes

Answer 346

Excises RNA primer

Answer 347

Joins DNA strands (especially between Okazaki fragments)

Answer 348

Reduces torsional strain from positive supercoils by introducing nicks in DNA strand Involved in DNA replication and transcription

Answer 349

The lagging strand, because it must constantly start and stop the process of DNA replication. Additionally, it contains many more RNA primers, all of which must be removed and filled in with DNA

Answer 350

The ends of eukaryotic chromosomes Contain repetitive sequences of noncoding DNA Protect the chromosome from losing important genes from the incomplete replication of the 5' end of the DNA strand

Answer 351

Code for cell cycle-promoting proteins; when mutated, a porto-oncogene becomes an oncogene, promoting rapid cell cycling (stepping on the gas pedal) Results in cancer through gain of function mutations

Answer 352

Code for repair or cell-cycle inhibiting proteins; when mutated, the cell cycle is allowed to proceed unchecked (cutting the brakes) Results in cancer through loss of function mutations

Answer 353

The parent strand is more heavily methylated, whereas the daughter strand is bare methylated at all

Answer 354

DNA polymerase

Answer 355

MSH2, MLH1 (MutS and MutL in prokaryotes)

Answer 356

Excision endonuclease

Answer 357

Glycosylase, AP endonuclease

Answer 358

Nucleotide excision repair corrects lesions that are large enough to distort the double helix Base excision repair corrects lesions that are small enough not to distort the double helix

Answer 359

Include all of the DNA in an organism's genome, including noncoding regions Useful for studying DNA in introns, centromeres or telomeres

Answer 360

Only include expressed genes from a given tissue, but can be used to express recombinant proteins or to perform gene therapy Contains only the exons of genes that are transcriptionally active in the sample tissue

Answer 361

Increases the number of copies of a given DNA sequence and can be used for a sample containing very few copies of the DNA sequence Used to clone a sequence of DNA using a DNA sample, a primer, free nucleotides and enzymes The polymerase from Thermus aquatics is used because the reaction is regulated by thermal cycling, which would denature human enzymes A primer must be prepared with a complementary sequence to part of the DNA of interest Repeated heating and cooling cycles allow the enzymes to act specifically and replaces helicase Each cycle of the polymerase chain reaction doubles the amount of DNA of interest

Answer 362

Useful when searching for a particular DNA sequence because it separates DNA fragments by length and then probes for a sequence of interest

Answer 363

Dideoxyribonucleotides lack the 3'-OH group that is required for DNA strand elongation. Thus, once a dideoxyribonucleotide is added to a growing DNA molecule, no more nucleotides can be added because dideoxyribonucleotides have no 3/-OH group with which to form a bond.

Answer 364

Transgenic mice have a gene introduced into their germ line or embryonic stem cells to look at the effects of that gene; they are therefore best suited for studying the effects of dominant alleles. Knockout mice are those in which a gene of interest has been removed, rather than added.

Answer 365

A macromolecule that stores genetic information in all living organisms

Answer 366

Deoxyribose

Answer 367

Adenine (A), cytosine (C), guanine (G), thymine (T) and uracil (U)

Answer 368

Adenine (A) and guanine (G)

Answer 369

Cytosine (C), thymine (T) and uracil (U)

Answer 370

No, it contains uracil (U) instead

Answer 371

Cyclic, planar, conjugated and contain 4n + 2 pi electrons (where n = any integer; Huckel's rule)

Answer 372

Ring structures that contain at least two different elements in the ring

Answer 373

Purines and pyrimidines are equal in number in a DNA molecule, and that because of base-pairing, the amount of adenine equals the amount of thymine, and the amount of cytosine equals the amount of guanine

Answer 374

B-DNA (i.e. right-handed helix)

Answer 375

Zigzag shaped Present in low concentrations Seen with high GC-content or high salt concentrations

Answer 376

Right-handed helix

Answer 377

Pulling apart DNA strands

Answer 378

Bringing back DNA strands together

Answer 379

Heat, alkaline pH, chemicals like formaldehyde and urea

Answer 380

H2A, H2B, H3 and H4

Answer 381

DNA with its associated histones

Answer 382

Dense, transcriptionally silent DNA that appears dark under light microscopy

Answer 383

Less dense, transcriptionally active DNA that appears light under light microscopy

Answer 384

The ends of chromosomes Contain high GC-contain to precent unraveling of the DNA During replication, they are slightly shortened, although this can be (partially) reversed by the enzyme telomerase

Answer 385

Located in the middle of chromosomes and hold sister chromatids together until they are separated during anaphase in mitosis They contain a high GC-contain to maintain a strong bond between chromatids

Answer 386

A set of specialized proteins that assist the DNA polymerases

Answer 387

1. Helicases unwind the DNA at the origin of replication, producing two replication forks on either side of the origin 2. Unwound strands are kept from reanneling or being degraded by single-stranded DNA-binding proteins 3. Supercoiling causes torsional strain on the DNA molecule, which can be released by DNA topoisomerases, with creates nicks in the DNA molecule 4. DNA cannot be synthesized without an adjacent nucleotide to hook onto, so a small RNA primer is put down by primase 5. DNA polymerase III (prokaryotes) or DNA polymerase alpha, delta and epsilon (eukaryotes) can then synthesize a new strand of DNA; they read the template DNA 3' tp 5' and synthesize the new strand 5' to 3' 6. RNA primers can be removed by DNA polymerase I (prokaryotes) or RNase H (eukaryotes), and filled in with DNA by DNA polymerase I (prokaryotes or DNA polymerase delta (eukaryotes) 7. DNA ligase can then fuse the DNA strands together to create one complete molecule

Answer 388

Semiconservative: one old parent strand and one new daughter strand is incorporated into each of the two new DNA molecules

Answer 389

Requires only one primer and can then be synthesized continuously in its entirety

Answer 390

Requires many primers and is synthesized in discrete sections called Okazaki fragments

Answer 391

Unchecked cell proliferation with the ability to spread by local invasion or metastasize (migrate to distant sites via the bloodstream or lymphatic system)

Answer 392

Occurs during replication | Excises incorrectly matched bases

Answer 393

Occurs during G2 phase of the cell cycle | Uses genes MSH2 and MLH1

Answer 394

Fixes helix-deforming lesions of DNA (such as thymine dimers) via a cut-and-patch process that requires an excision endonuclease

Answer 395

Fixes nondeforming lesions of the DNA helix (such as cytosine deamination) by removing the base, leaving an apurinic/apyrimidinic (AP) site. An Ap endonuclease then removes the damaged sequence, which can be filled in with the correct bases.

Answer 396

DNA composed of nucleotides from two different sources

Answer 397

introduces a fragment of DNA into a vector plasmid

Answer 398

Cuts both the plasmid and the fragment, which are left with sticky ends Once the fragment binds to the plasmid, it can be introduced into a bacterial cell and permitted to replicate, generating many copies of the fragment of interest Vectors contain an origin of replication, the fragment of interest, and at least one gene for antibiotic resistance (to permit for selection of that colony after replication) Once replicated, the bacterial cells can be used to create a protein of interest from the vector

Answer 399

The joining of complementary base pair sequences

Answer 400

By size, using agarose gel electrophoresis

Answer 401

A method of curing genetic deficiencies by introducing a functional gene with a viral vector

Answer 402

Created by integrating a gene of interest into the germ line or embryonic stem cells of a developing mouse

Answer 403

Organisms that contain cells from two different lineages

Answer 404

Created by deleting a gene of interest

Answer 405

Every atom in the ring must have at least one unhybridized p-orbital (alternating double or triple bonds)

Answer 406

Results from the reverse transcription of processed mRNA

Answer 407

Gene therapy, Southern blotting and DNA repair

Answer 408

Cytosine degradation results in uracil One common DNA mutation is the transition from cytosine to uracil in the presence of heat. DNA repair enzymes recognize uracil and correct this error by excising the base and inserting cytosine. RNA exists only transiently in the cell, such that cytosine degradation is insignificant. Were uracil to be used in DNA under normal circumstances, it would be impossible to tell if a base should be uracil or if it is a damaged cytosine nucleotide.

Answer 409

Carries information from DNA by traveling from the nucleus (where it is transcribed) to the cytoplasm (where it is translated)

Answer 410

Translates nucleic acids to amino acids by pairing its anticodon with mRNA codons It is charged with an amino acid, which can be added to the growing peptide chain

Answer 411

Forms much of the structural and catalytic component of the ribosome, and acts as a ribozyme to create peptide bonds between amino acids

Answer 412

Methionine

Answer 413

UAA, UGA and UAG

Answer 414

Refers to the fact that the third base in a codon often plays no role in determining which amino acid is translated from that codon. This is protective because mutations in the wobble position will not have any effect on the protein translated from that gene.

Answer 415

Substitution of bases in the wobble position, introns or noncoding DNA

Answer 416

Substitution of one base, creating an mRNA codon that matches a different amino acid

Answer 417

Substitution of one base, creating a stop codon

Answer 418

Insertion or deletion of bases, creating a shift in the reading frame of the mRNA

Answer 419

No change is observed

Answer 420

One amino acid is changed in the protein; variable effects on function depending on specific change

Answer 421

Early truncation of protein; variable effects on function, but usually more severe than missense mutations

Answer 422

Change in most amino acids after the site of insertion deletion; usually the most severe of the types of mutations

Answer 423

Synthesizes most rRNA

Answer 424

Synthesizes mRNA (hnRNA) and snRNA Binds to the TATA box within the promoter region of the gene (25 base pairs upstream from the first transcribed base)

Answer 425

Synthesizes tRNA and some rRNA

Answer 426

RNA polymerase II binds to the TATA box, which is located within the promoter region of a relevant gene, at about -25

Answer 427

1. Splicing: removal of introns, joining of exons :: Uses snRNA and snRNPs in the spliceosome to create a lariat (made of introns), which is then degraded. Exons are ligated together 2. 5' cap: addition of a 7-methylguanylate triphosphate cap to the 5' end of the transcript 3. 3' poly-A tail: addition of adenosine bases to the 3' end to protect against degradation

Answer 428

The ability of some genes to use various combinations of exons to create multiple proteins from one hnRNA transcript. This increases protein diversity and allows a species to maximize the number of proteins it can create from a limited number of genes

Answer 429

Initiation, elongation and termination

Answer 430

Binds incoming aminoacyl-tRNA using codon-anticodon pairing

Answer 431

Holds growing polypeptide until peptide transferase forms peptide bond and polypeptide is handed to A site

Answer 432

Transiently holds uncharged tRNA as it exits the ribosome

Answer 433

Proper folding by chaperones, formation of quaternary structure, cleavage of proteins or signal sequences, and covalent addition of other biomolecules (phosphorylation, carboxylation, glycosylation, prenylation)

Answer 434

Negative repressible system

Answer 435

Negative inducible system

Answer 436

Regulator gene, promoter site, operator site, structural gene

Answer 437

Require the binding of a protein to the operator site to increase transcription

Answer 438

Require the binding of a protein to the operator site to decrease transcription

Answer 439

Transcribed to form repressor protein

Answer 440

Site of RNA polymerase binding (similar to promoters in eukaryotes)

Answer 441

Binding site for repressor protein

Answer 442

The gene of interest; its transcription is dependent on the repressor being absent from the operator site

Answer 443

Signal molecules include steroid hormones and second messengers, which kind to their receptors in the nucleus. These receptors are transcription factors that use their DNA-binding domain to attach to a particular sequence in DNA called a response element. Once bonded to the response element, these transcription factors can then promote increased expression of the relevant gene.

Answer 444

Histone deacetylation and DNA methylation will both down regulate the transcription of a gene. These processes allow the relevant DNA to be clumped more tightly, increasing the proportion of heterochromatin.

Answer 445

DNA is transcribed to RNA, which is translated to protein

Answer 446

Silent, nonsense (truncation) and missense mutations

Answer 447

Have no effect on protein synthesis

Answer 448

Produce a premature stop codon

Answer 449

Produce a codon that codes for a different amino acid

Answer 450

Result from nucleotide addition or deletion | Change the reading frame of subsequent codons

Answer 451

Messenger RNA (mRNA), transfer RNA (tRNA) and ribosomal RNA (rRNA)

Answer 452

Synthesized from the DNA template (antisense) strand

Answer 453

Polycistronic genes :: starting transcription in different sites within the gene, leading to different gene products

Answer 454

Alternative splicing :: combining different exons in a modular fashion to acquire different gene products

Answer 455

Occurs when the 30S ribosome attaches to the Shine-Dalgarno sequence and scans for a start codon; it lays down N-formylmethionine in the P site of the ribosome

Answer 456

Occurs when the 40S ribosome attaches to the 5' cap and scans for a start codon; it lays down methionine in the P site of the ribosome

Answer 457

Involves the addition of a new aminoacyl-tRNA into the A site of the ribosome and transfer of the growing polypeptide chain from the tRNA in the P site to the tRNA in the A site. The now uncharged tRNA pauses in the E site before exiting the ribosome

Answer 458

Occurs when the codon in the A site is a stop codon; release factor places a water molecule on the polypeptide chain and thus releases the protein

Answer 459

Explains how operons work

Answer 460

Inducible or repressible clusters of genes transcribed as a single mRNA

Answer 461

e.g. lac operon Bonded to a repressor under normal conditions Can be turned on by an inducer pulling the repressor from the operator site

Answer 462

e.g. trp operon Transcribed under normal conditions Can be tuned off by a corepressor coupling with a repressor and the binding of this complex to the operator site

Answer 463

Search for promoter and enhancer regions in the DNA

Answer 464

Within 25 base pairs of the transcription start site

Answer 465

More than 25 base pairs away from the transcription start site Transcriptional regulatory sequences that function by enhancing the activity of RNA polymerase at a single promoter site

Answer 466

It catalyzes the formation of a peptide bond between the incoming amino acid in the A site and the growing polypeptide chain in the P site

Answer 467

Transporting charged tRNA molecules into the ribosome and advancing the ribosome down the mRNA transcript

Answer 468

Maintain a protein's 3D shape as it is formed

Answer 469

None : They all require energy

Answer 470

trp operon during abundance of tryptophan

Answer 471

shRNA (short hairpin RNA) It is a useful in biotechnology tool using in RNA interference. It is not, however, produced in the nucleus for use in the spliceosome. It targets mRNA to be degraded in the cytoplasm; it is not utilized in splicing of the hnRNA (heterogeneous nuclear RNA) and snRNPs (small nuclear ribonucleoproteins), however, do bind to the hnRNA to induce splicing.

Answer 472

rRNA RNA polymerase I in eukaryotes is found in the nucleolus and is in charge of transcribing most of the rRNA for use during ribosomal creation. RNA polymerase II is responsible for hnRNA and snRNA. RNA polymerase III is responsible for tRNA and the 5S rRNA.

Answer 473

Antisense mRNA to the one produced The mRNA produced has the same structure as the sense strand of DNA (with uracils instead of thymines). Because bonding of nucleic acids is always complementary but antiparallel, the antisense strand of mRNA would be the one that binds to the produced mRNA, creating double-stranded RNA that is then degraded once found in the cytoplasm.

Answer 474

Responsible for the movement of phospholipids between the layers of the plasma membrane because it is otherwise energetically unfavorable Specific membrane proteins that maintain the bidirectional transport of lipids between the layers of the phospholipid bilayer in cells

Answer 475

Aggregates of specific lipids in the membrane that function as attachment points for other biomolecules and play roles in signaling

Answer 476

1. Lipids (including phospholipids and cholesterol) 2. Proteins (including transmembrane proteins [channels and receptors], membrane associated proteins, and embedded proteins) 3. Carbohydrates (including the glycoprotein coat and signaling molecules) 4. Nucleic acids

Answer 477

Moderates membrane fluidity by interfering with the crystal structure of the cell membrane and occupying space between phospholipid molecules at low temperatures, and by restricting excessive movement of phospholipids at high temperatures Provides stability by cross-linking adjacent phospholipids through interactions at the polar head group and hydrophobic interactions at the nearby fatty acid tail

Answer 478

Transmembrane proteins, embedded membrane proteins, membrane associated (peripheral) proteins

Answer 479

Serve as channels or receptors | Can have one or more hydrophobic domains

Answer 480

Have catalytic activity linked to nearby enzymes | Cellular communication

Answer 481

Involved in signaling or are recognition molecules on the extracellular surface

Answer 482

Allow for the intercellular transport of materials between adjacent cells and do not prevent paracellular transport of materials Exist in discontinuous bunches around the cell

Answer 483

Not used for intercellular transport but do prevent paracellular transport Form bands around the cell

Answer 484

As osmotic pressure increases, more water will tend to follow into the compartment to decrease solute concentration Osmotic pressure is often considered a "sucking" pressure because water will move towards the compartment with the highest osmotic pressure

Answer 485

Primary active transport and secondary active transport

Answer 486

Uses ATP as an energy source for the movement of molecules against their concentration gradient

Answer 487

Uses an electrochemical gradient to power the transport

Answer 488

Moves both particles in secondary active transport across the membrane in the same direction

Answer 489

Moves particles in secondary active transport across the membrane in opposite directions

Answer 490

Symport and antiport

Answer 491

Sodium-potassium pumps and leak channels

Answer 492

The inner mitochondrial membrane lacks cholesterol

Answer 493

There is no pH gradient between the cytoplasm and the intermembrane space because the outer mitochondrial membrane has such high permeability to biomolecules (the potion-motive force of the mitochondria is across the inner mitochondrial membrane, not the other mitochondrial membrane)

Answer 494

(E) = RT / zF ln ([ion]outside / [ion]inside) = 61.5 / z log ([ion]outside / [ion]inside) Calculates the electrical potential created by one ion

Answer 495

Vm = 61.5 log ([{P Na+ x [Na+]outside} + {P K+ x [K+]outside} + {P Cl- x [Cl-]inside}] / [{P Na+ x [Na+]inside} + {P K+ x [K+]inside} + {P Cl- x [Cl-]outside}]) Calculates the resting membrane potential at physiological temperature Derived from the Nernst equation

Answer 496

Accounts for the presence of lipids, proteins, and carbohydrates in a dynamic, semisolid plasma membrane that surrounds cells

Answer 497

lipid rafts

Answer 498

Yes, but their movement is slowed by their relatively large size

Answer 499

Phospholipid precursors | Found in low levels in the cell membrane

Answer 500

Phospholipid precursors | Found in low levels in the cell membrane

Answer 501

Replace one fatty acid with a phosphate group, which is often linked to other hydrophilic groups

Answer 502

Present in large amounts in the cell membrane and contributes to membrane fluidity and stability

Answer 503

Present in small amounts in the cell membrane (if at all) and are Mose prevalent in plants and function in waterproofing and defense

Answer 504

Act as transporters, cell adhesion molecules and enzymes

Answer 505

Form a protective glycoprotein coat | Function in cell recognition

Answer 506

Bind to membrane receptors, which function as channels or enzymes in second messengers pathways

Answer 507

Cap, tight and desmosomes and hemidesmosomes

Answer 508

Anchor layers of epithelial tissue together

Answer 509

Help to determine appropriate membrane transport mechanisms in cells

Answer 510

A colligative property The pressure applied to a pure solvent to prevent osmosis and is used to express the concentration of the solution Conceptualized as a sucking pressure in which a solution is drawing water in, proportional to its concentration

Answer 511

Does not require energy because the molecule is moving down its concentration gradient or from an area with higher concentration to an area with lower concentration

Answer 512

Simple, osmosis and facilitated

Answer 513

Does not require a transported Small, non polar molecules passively move from an area of high concentration to an area of low concentration until equilibrium is achieved

Answer 514

The diffusion of water across a selectively permeable membrane

Answer 515

Uses transport proteins to move impermeable solutes across the cell membrane

Answer 516

Requires energy in the form of ATP or an existing favorable ion gradient

Answer 517

Endocytosis and exocytosis

Answer 518

The ingestion of liquid into the cell in vesicles formed from the cell membrane

Answer 519

The ingestion of large, solid molecules into the cell in vesicles formed from the cell membrane

Answer 520

A difference in the number of positive and negative charges on either side of the membrane

Answer 521

By moving three sodium ions out of the cell for every two potassium ions pumped in

Answer 522

By allowing the passive transport of ions

Answer 523

1. The outer mitochondrial membrane is highly permeably to metabolic molecules and small proteins 2. The inner mitochondrial membrane surrounds the mitochondrial matrix, where the citric acid cycle produces electrons used in the electron transport chain and where many other enzymes important in cellular respiration are located 3. The inner mitochondrial membrane does not contain cholesterol

Answer 524

Facilitated diffusion

Answer 525

Treatment with ouabain increases intracellular concentrations of sodium

Answer 526

The differential distribution ions across the membrane Active transport processes Selective permeability of the phospholipid bilayer

Answer 527

Cytoskeletal attachment, transport regulation, and second messenger reservoir

Answer 528

In ribosomes

Answer 529

Phospholipids moving within the plane of the membrane Movement of individual molecules in the cell membrane will be affected by size and polarity, just as with diffusion Lipids are much smaller than proteins in the plasma membrane and will more more quickly Lipids will move fastest within the plane of the cell membrane because the polar head group does not need to pass through the hydrophobic tail region in the same way that it would if it were moving between the membrane layers

Answer 530

Transmembrane protein with catalytic activity

Answer 531

Cell-cell junctions that are found in plants, not animals

Answer 532

They both rely on the electrochemical gradient of only the compound of interest

Answer 533

No, because the resting membrane potential creates a state that is capable of responding to stimuli. Signaling molecules and channels would not be useful with a membrane potential of zero.

Answer 534

Liver and pancreas

Answer 535

Adipose tissue and muscle

Answer 536

High (~15 mM)

Answer 537

Low (~5 mM)

Answer 538

No | It cannot be saturated under normal physiological conditions

Answer 539

Yes | It is saturated when glucose levels are only slightly above 5 mM

Answer 540

No, but it serves as glucose sensor to cause release of insulin in pancreatic beta-cells

Answer 541

GLUT 4 is saturated when glucose levels are only slightly above 5 mM, so glucose entry can only be increased by increasing the number of transporters. Insulin promotes the fusion of vesicles containing preformed GLUT 4 with the cell membrane

Answer 542

Glucose --(phosphorylation)--> glucose 6-phosphate (G6P) Traps glucose in the cell

Answer 543

Inhibited by glucose 6-phosphate (G6P)

Answer 544

Glucose --(phosphorylation)--> glucose 6-phosphate (G6P) Traps glucose in the cell Only works in the liver and pancreas Works with GLUT 2 as part of the glucose sensor in beta-islet cells

Answer 545

Inhibited by insulin the liver

Answer 546

Fructose 6-phosphate (F6P) --(phosphorylation + ATP)--> fructose 1,6-bisphosphate (F1,6BP) Rate-limiting step in glycolysis

Answer 547

Inhibited by ATP, citrate and glucagon | Activated by AMP, fructose 2,6-bisphosphate (F2,6BP) and insulin

Answer 548

Glyceraldehyde 3-phosphate (G3P) --(phosphorylation)--> 1,3-bisphosphoglycerate (1,3BPG) + NADH

Answer 549

1,3-bisphosphoglycerate (1,3BPG) + ADP --(substrate-level phosphorylation)--> 3-phosphoglycerate (3PG) + ATP

Answer 550

Phosphoenolpyruvate (PEP) + ADP (substrate-level phosphorylation)--> pyruvate + ATP

Answer 551

Activated by fructose 1,6-bisphosphate (F1,6BP)

Answer 552

Fermentation must occur to regenerate NAD+, which is in limited supply in cells. Fermentation generates no ATP or energy carriers; it merely regenerates the coenzymes needed in glycolysis

Answer 553

The binding of 2,3-BPG decreases hemoglobin's affinity for oxygen. Fetal hemoglobin must be able to steal oxygen from maternal hemoglobin at the placental interface; therefore, it would be disadvantageous to lower its affinity for oxygen

Answer 554

Galactokinase

Answer 555

Galactose-1-phosphate uridyltransferase

Answer 556

Fructokinase

Answer 557

Aldolase B

Answer 558

Phosphorylates galactose, trapping it in the cell

Answer 559

Galactose --> glucose 1-phosphate + epimerase, linking glycolysis to galactose metabolism

Answer 560

Works with hexokinase to phosphorylate fructose, trapping it in the cell

Answer 561

Produces dihydroxyacetone phosphate (DHAP) and glyceraldehyde. Glyceraldehyde can be phosphorylated to glyceraldehyde 3-phosphate, linking glycolysis to fructose metabolism

Answer 562

Pyruvate, NAD+ and CoA

Answer 563

Acetyl-CoA, NADH and CO2

Answer 564

Acetyl-CoA inhibits the PDH complex. As a product of the enzyme complex, a buildup of acetyl-CoA from either the citric acid cycle or fatty acid oxidation signals that the cell is energetically satisfied and that the production of acetyl-CoA should be slowed or stopped. Pyruvate can then be used to form other products, such as oxaloacetate for use in gluconeogenesis.

Answer 565

A core protein of glycogenin with linear chains of glucose emanating out from the center. Some of these chains are branches

Answer 566

Alpha-1,4 glycosidic links (linear) | Alpha-1,6 glycosidic links (branched)

Answer 567

Glycogen synthase and branching enzyme

Answer 568

Attaches the glucose molecule from UDP-glucose to the growing glycogen chain, forming an alpha-1,4 link in the process

Answer 569

Creates a branch by breaking an alpha-1,4 link in the growing chain and moving a block of oligoglucose to another location in the glycogen granule. The oligoglucose is then attached with an alpha-1,6 link

Answer 570

Glycogen phosphorylase and debranching enzyme

Answer 571

Removes a glucose molecule from glycogen using a phosphate, breaking the alpha-1,4 link and creating glucose 1-phosphate

Answer 572

Moves all of the glucose from a branch to a longer glycogen chain by breaking an alpha-1,4 link and forming a new alpha-1,4 link to the longer chain. The branch point is left behind; this is removed by breaking the alpha-1,6 link to form a free molecule of glucose

Answer 573

When an individual has been fasting for >12 hours To carry out gluconeogenesis, hepatic (and renal) cells must have enough energy to drive the process of glucose creation, which requires sufficient fat stops to under beta-oxidation

Answer 574

Pyruvate carboxylase, phosphoenolpyruvate carboxylase (PEPCK), fructose-1,6-bisphosphatase, and glucose-6-phosphatase

Answer 575

Pyruvate kinase

Answer 576

Pyruvate kinase

Answer 577

Phosphofructokinase-1 (PFK-1)

Answer 578

Glucokinase

Answer 579

Acetyl-CoA inhibits PDH complex while activated pyruvate carboxylase. The net effect is to shift from burning pyruvate in the citric acid cycle to creating new glucose molecules for the rest of the body. The acetyl-CoA for this regulation comes predominantly from beta-oxidation, not glycolysis.

Answer 580

Ribulose 5-phosphate and NADPH

Answer 581

Involved in lipid biosynthesis Bacterial bleach formation uncertain while blood cells Maintenance of glutathione stores to protect against reactive oxygen species

Answer 582

Found in the liver (for glucose storage) and pancreatic beta-islet cells (as part of the glucose sensor) Has a high Km value

Answer 583

Found in adipose tissue and muscle Stimulated by insulin Has a low Km value

Answer 584

In the cytoplasm

Answer 585

``` Glucokinase Hexokinase Phosphodructokinase-1 (PFK-1) Phosphofructokinase-2 (PFK-2) Glyceraldehyde-3-phosphate dehydrogenase 3-phosphoglycerate kinase Pyruvate kinase ```

Answer 586

``` Pancreatic beta-islet cells (part of the glucose sensor) Liver cells (responds to insulin) ```

Answer 587

Peripheral tissues

Answer 588

PFK-1: fructose 6-phosphate --> fructose 1,6-bisphosphate

Answer 589

AMP and fructose 2,6-bisphosphate (F2,6-BP)

Answer 590

ATP and citrate

Answer 591

Produces F2,6-BP, which activates PFK-1

Answer 592

3-phosphoglycerate kinase and pyruvate kinase

Answer 593

Making ATP by placing an inorganic phosphate (Pi) onto ADP

Answer 594

Glucokinase/hexokinase PFK-1 Pyruvate kinase

Answer 595

It is oxidized by the mitochondrial electron transport chain

Answer 596

It is oxidized by cytoplasmic lactate dehydrogenase | e.g. RBCs, skeletal muscles (during short, intense Burts of exercise) and any cell deprived of oxygen

Answer 597

From lactose in milk

Answer 598

Galactokinase

Answer 599

From honey, fruit and sucrose (common table sugar)

Answer 600

Fructokinase

Answer 601

Acetyl-CoA

Answer 602

Glycogen synthesis

Answer 603

The breakdown of glycogen

Answer 604

Epinephrine and AMP

Answer 605

In the liver and kidney cells' cytoplasm and mitochondria

Answer 606

The reverse of glycolysis, using the same enzymes except pyruvate kinase, PFK-1 and glucokinase

Answer 607

Pyruvate --> oxaloacetate

Answer 608

Oxaloacetate --> phosphoenolpyruvate

Answer 609

Acetyl-CoA (from beta-oxidation)

Answer 610

Glucagon and cortisol

Answer 611

Fructose 1,6-bisphosphate --> fructose 6-phosphate

Answer 612

Fructose-1,6-bisphosphatase: fructose 1,6-bisphosphate --> fructose 6-phosphate

Answer 613

Glucagon (via decreased levels of fructose 2,6-bisphosphate)

Answer 614

Insulin (via increased levels of fructose 2,6-bisphosphate)

Answer 615

Glucose 6-phosphate --> glucose

Answer 616

Endoplasmic reticulum of liver cells

Answer 617

Glucose-6-phosphate dehydrogenase

Answer 618

NADP+ and insulin

Answer 619

Anaerobic glycolysis in muscles

Answer 620

No because it can produce its own glucose through gluconeogenesis

Answer 621

No because it can produce its own glucose through gluconeogenesis

Answer 622

Carboxylated to oxaloacetate for entry into gluconeogenesis

Answer 623

Debranching enzyme complex

Answer 624

Increased pyruvate concentration

Answer 625

No, because it is used to raise blood sugar. After eating, blood sugar is already high.

Answer 626

Glucose-6-phosphate dehydrogenase PPP's responsibility is generating NADPH. In individuals with G6PD deficiency, NADPH cannot be produced at sufficient levels and oxidative stresses lead to cell membrane and protein (hemoglobin) damage

Answer 627

Pyruvate + CoA-SH + NAD+ --> acetyl-CoA + CO2 + NADH + H+

Answer 628

Fatty acids, ketogenic amino acids, ketones, and alcohol

Answer 629

Shuttle acyl group from cytosolic CoA-SH to mitochondrial CoA-SH via carnitine --> undergo beta-oxidation Fatty acid couples with CoA in the cytosol --> fatty acyl-CoA --(moves into the intermembrane space)--> the fatty acid group (acyl group) is transferred to carnitine --> acyl-carnitine --(crosses the inner membrane)--> the acyl group is transferred to a mitochondrial CoA --> fatty acyl-CoA reforms --(undergoes beta oxidation)--> acetyl-CoA

Answer 630

Transaminate to lose nitrogen --> convert carbon skeleton into ketone body --> ketone body is converted into acetyl-CoA

Answer 631

Reverse of ketone body formation

Answer 632

Alcohol dehydrogenase and acetaldehyde dehydrogenase convert alcohol into acetyl-CoA

Answer 633

Complete oxidation of carbons in intermediates to CO2 so that reduction reactions can be coupled with CO2 formation, thus forming energy carriers such as NADH and FADH2 for the electron transport chain

Answer 634

Isocitrate dehydrogenase

Answer 635

Citrate synthase Isocitrate dehydrogenase Alpha-ketoglutarate complex

Answer 636

ATP NADH Succinyl-CoA Citrate

Answer 637

ATP | NADH

Answer 638

ATP NADH Succinyl-CoA

Answer 639

ADP | NAD+

Answer 640

ADP | Ca^2+

Answer 641

Complex I, III and IV

Answer 642

Complex II

Answer 643

Complex IV

Answer 644

The electron transport chain generates the proton-motive force, an electrochemical gradient across the inner mitochondrial membrane, which provides the energy for ATP synthase to function

Answer 645

The malate-aspartate shuttle This mechanism is the more efficient one, it makes sense for a highly aerobic organ such as the heart to utilize it in order to maximize its ATP yield

Answer 646

The ETC is made up of the physical set of inter membrane proteins located on the inner mitochondrial matrix, and they undergo oxidation-reduction reactions as they transfer electrons to oxygen, the final electron acceptor. As electrons are transferred, a proton-motive force is generated in the intermembrane space. Oxidative phosphorylation is the process by which ATP is generated via harnessing the proton gradient, and it utilizes ATP synthase to do so.

Answer 647

As electrons are transferred to oxygen in ETC, a proton-motive force is generated in the inter membrane space and oxidative phosphorylation uses that proton gradient to make ATP

Answer 648

By splitting up electron transfer into several complexes, enough energy is released to facilitate the creation of a proton gradient at many locations, rather than just one. The greater the proton gradient is, the greater the ATP generation will be. Direct reduction of oxygen by NADH would release a significant amount of energy to the environment, resulting in inefficient electron transport.

Answer 649

Contains a high-energy thirster bond that can be used to drive other reactions when hydrolysis occurs

Answer 650

A five-enzyme complex in the mitochondrial matrix that forms, and is also inhibited by, acetyl-CoA and NADH

Answer 651

``` Pyruvate dehydrogenase (PDH) Dihydrolipoyl transacetylase Dihydrolipoyl dehydrogenase Pyruvate dehydrogenase kinase Pyruvate dehydrogenase phosphatase ```

Answer 652

Pyruvate --(oxidation)--> CO2 + 2 carbon molecule Requires thiamine pyrophosphate (vitamin B1, TPP) and Mg^2+

Answer 653

2 carbon molecule --(oxidation)--> acetyl group Transfers acetyl group to CoA --> acetyl-CoA Uses lipoic acid

Answer 654

Reoxidizes lipoic acid --> FADH2 (which can later transfer electrons to NAD+ --> NADH, which can then feed into ETC) Uses FAD

Answer 655

PDH --(phosphorylation)--> PDH turned off Activated when ATP or Acetyl-CoA are present

Answer 656

PDH --(dephosphorylation)--> PDH turned on Activated when ADP levels are high

Answer 657

The mitochondrial matrix

Answer 658

Oxidize carbon in intermediates to CO2 and generate high-energy electron carries (NADH and FADH2) and GTP

Answer 659

``` Citrate synthase Aconitase Isocitrate dehydrogenase Alpha-ketoglutarate dehydrogenase complex Succinyl-CoA synthetase Succinate dehydrogenase Fumarase Malate dehydrogenase ```

Answer 660

Couples acetyl-CoA to oxaloacetate --(hydrolysis)--> citrate + CoA-SH

Answer 661

Negative feedback from ATP, NADH, succinyl-CoA and citrate

Answer 662

Citrate --(isomerize)--> isocitrate

Answer 663

Isocitrate --(oxidation and decarboxylation)--> alpha-ketoglutarate Generates the first CO2 and first NADH of the cycle The rate-limiting step of the citric acid cycle

Answer 664

Inhibitors: ATP and NADH Activators: ADP and NAD+

Answer 665

Alpha-ketoglutarate --(metabolism)--> succinyl-CoA Acts like the PDH complex Generates the second CO2 and second NADH of the cycle

Answer 666

Inhibition: ATP, NADH and succinyl-CoA Activation: ADP and Ca^2+

Answer 667

Succinyl-CoA --(hydrolysis of thirster bond)--> succinate + CoA-SH Generates the one GTP generated in the citric acid cycle

Answer 668

Succinate --(succinate dehydrogenase)--> fumarate A flavoprotein that is anchored in the inner mitochondrial membrane because it requires FAD, which is reduced to form the one FADH2 generated in the citric acid cycle

Answer 669

Fumarate --(hydrolysis of the alkene bond)--> malate

Answer 670

Malate --(oxidation)--> oxaloacetate Generates the third and final NADH of the cycle

Answer 671

On the matrix-facing surface of the inner mitochondrial membrane

Answer 672

NADH donates electrons to the chain, which are passed from one complex to the next As ETC progresses, reduction potentials increase until oxygen, which has the highest reduction potential, receives the electrons

Answer 673

I (NADH-CoQ oxidoreductase) II (Succinate-CoQ oxidoreductase) III (CoQH2-cytochrome c oxidoreductase) IV (cytochrome c oxidase)

Answer 674

Transfers electrons from NADH to flavin mononucleotide (FMN) --> transfers electrons from FMN to coenzyme Q (CoQ) --> CoQH2 forms 4 H+ are translocated Uses an iron-sulfur cluster

Answer 675

Transfers electrons from succinate to FAD --> transfers electrons from FAD to CoQ --> CoQH2 forms No H+ are translocated Uses an iron-sulfur cluster

Answer 676

Transfers electrons from CoQH2 to heme --> cytochrome c forms as part of the Q cycle 4 H+ are translocated Uses an iron-surfer cluster

Answer 677

Transfers electrons in the form of hydride ions (H-) from cytochrome c to oxygen --> water forms 2 H+ are translocated Uses Cu^2+

Answer 678

Using glycerol 3-phosphate shuttle or malate-aspartate shuttle

Answer 679

Electrons are transferred from NADH to dihydroxyacetone phosphate (DHAP) --> glycerol 3-phosphate forms Electrons then move to mitochondrial FAD --> FADH2 forms

Answer 680

Electrons are transferring from NADH to oxaloacetate --> malate forms --> Malate crosses the inner mitochondrial membrane --> Malate transfers electrons to mitochondrial NAD+ --> NADH forms

Answer 681

The electrochemical gradient generated by the electron transport chain across the inner mitochondrial membrane

Answer 682

The innermembrane space This gradient stores energy, which can be used to form ATP via chemiosmotic coupling

Answer 683

The enzyme responsible for generating ATP from ADP and inorganic phosphate (Pi) Has an F0 portion and an F1 portion

Answer 684

AN ion channel | Allows protons to flow down the gradient from the intermembrane space to the matrix

Answer 685

Uses the energy released by the gradient to phosphorylate ADP into ATP

Answer 686

2 NADH | 2 ATP

Answer 687

1 NADH/molecule of pyruvate | 2NADH/molecule of glucose

Answer 688

3 NADH + 1 FADH2 + 1 GTP/pyruvate molecule | 6 NADH + 2 FADH2 + 2 GTP/ glucose molecule

Answer 689

25 ATP (from total NADH) + 3 ATP (from total FADH2) + 2 ATP (from total GTP) + 2 ATP (from glycolysis) = 32 ATP

Answer 690

Acetyl-CoA

Answer 691

Inner mitochondrial membrane

Answer 692

Thioester hydrolysis has a higher energy yield

Answer 693

Because electron transfer from cytosol to matrix can take more than one pathway

Answer 694

It causes depletion of glycogen stores Uncouplers inhibit ATP synthesis without affecting the electron transport chain. Because the body must burn more fuel to maintain the proton-motive force, glycogen stores will be mobilized to feed into glycolysis, then the TCA and finally oxidative phosphorylation.

Answer 695

Complex II

Answer 696

An electrochemical proton gradient

Answer 697

Physical digestion: accomplished in the mouth and stomach, reducing the particle size

Answer 698

Chemical digestion: small intestine, pancreatic lipase, collapse, cholesterol esterase and bile Absorption occurs in a more distal portion of the small intestine

Answer 699

No, small free fatty acids enter the circulation directly

Answer 700

In the post absorptive and prolonged fasting states, lipid mobilization is favored. A decrease in insulin levels, as well as an increase in epinephrine or cortisol, will increase lipid mobilization from adipocytes.

Answer 701

3:1 (a triacylglycerol molecule is composed of glycerol and three fatty acids)

Answer 702

Free fatty acids remain in the blood, bonded to albumin and other carrier proteins A smaller amount will remain unbounded

Answer 703

1. HDL 2. LDL 3. IDL 4. VLDL 5. chylomicrons VLDL and chylomicrons are the primary triacylglycerol transporters HDL and LDL are mostly involved in cholesterol transport

Answer 704

Intestine and liver

Answer 705

The absence of cholesterol | Stimulated by insulin

Answer 706

smooth endoplasmic reticulum

Answer 707

LCAT catalyzes the esterification of cholesterol to form cholesteryl esters CETP promotes the transfer of cholesterol esters from HDL to IDL, forming LDL

Answer 708

1. Attachment to acyl carrier protein 2. Bond formation between molecules 3. Reduction of carbonyl group 4. Dehydration 5. Reduction of double bond

Answer 709

There is an additional isomerase and an additional reductase for the beta-oxidation of unsaturated fatty acids, which provide the stereochemistry necessary for further oxidation

Answer 710

Fatty acid degradation results in large amounts of acetyl-CoA, which cannot enter the gluconeogenic pathway to produce glucose. Only odd-numbered fatty acids can act as a source of carbon for gluconeogenesis; even then, only the final malonyl-CoA molecule can be used. Energy is packaged into ketone bodies for consumption by the brain and muscles

Answer 711

Prolonged fast Occurs in the liver Stimulated by increasing concentrations of acetyl-CoA

Answer 712

Prolonged fast Stimulated by a low-energy state in muscle and brain tissues Does not occur in the liver

Answer 713

No | Proteins are more valuable to the cell than lipids, thus they will not commonly be broken down for lipid synthesis

Answer 714

Small intestine

Answer 715

Transported to the liver for processing into glucose or ketone bodies

Answer 716

Will feed into the urea cycle for excretion

Answer 717

Processed depending on their composition Basic chains: will be processed like amino acids (will feed into the urea cycle for excretion) Other functional groups: will be treated like the carbon skeleton (transported to the liver for processing into glucose or ketone bodies)

Answer 718

Mouth and stomach

Answer 719

Small intestine

Answer 720

Bile, pancreatic lipase, collapse and cholesterol esterase

Answer 721

They can either form micelles for absorption or be absorbed directly

Answer 722

Across the intestine into the blood

Answer 723

As micelles and assembled into chylomicrons for release into the lymphatic system

Answer 724

Hormone-sensitive lipase

Answer 725

Lipoprotein lipase

Answer 726

Transport mechanism for dietary triacylglycerol molecules and are transported via the lymphatic system

Answer 727

Transports newly synthesized triacylglycerol molecules from the liver to peripheral tissues in the bloodstream

Answer 728

VLDL remnant in transition between triacylglycerol and cholesterol transport Picked up cholesteryl esters from HDL

Answer 729

Primarily transports cholesterol for use by tissues

Answer 730

Involved in the reverse transport of cholesterol

Answer 731

Control interactions between lipoproteins

Answer 732

Dietary sources | de novo synthesis in the liver

Answer 733

Synthesis of a complex molecule, which refers to the biochemical pathway where a complex biomolecule is synthesized anew from simple molecules

Answer 734

HMG-CoA reductase

Answer 735

Catalyzes the formation of cholesteryl esters for transport with HDL

Answer 736

Catalyzes the transient of IDL to LDL by transferring cholesteryl esters from HDL

Answer 737

Carboxylic acids, typically with a single long chain, although they can be branched

Answer 738

Have no double bonds between carbons

Answer 739

Have one or more double bonds

Answer 740

Location: cytoplasm (from acetyl-CoA) and transported out of the mitochondria Steps: activation, bond formation, reduction, dehydration and another reduction (repeated 8 times to form palmitic acid)

Answer 741

Palmitic acid

Answer 742

Location: mitochondria (following transport by the carnitine shuttle) Steps: beta-oxidation uses cycles of oxidation, hydration, oxidation and cleavage (branched and unsaturated fatty acids require special enzymes -- unsaturated fatty acids use isomerase and an additional reductase during cleavage)

Answer 743

Form ketogenesis during a prolonged starvation state due to excess acetyl-CoA in the liver

Answer 744

Regenrated acetyl-CoA for use as an energy source in peripheral tissues

Answer 745

2/3 of its original energy capacity

Answer 746

Small intestine

Answer 747

Under conditions of starvation

Answer 748

Energy (through gluconeogenesis or ketone body formation)

Answer 749

Urea cycle (for excretion)

Answer 750

HSL is activated and free fatty acids are released During fatty acid mobilization, there is a breakdown of triacylglycerols in adipocytes by hormone-sensitive lipase (HSL). This breakdown results in the release of three fatty acids and a glycerol molecule. The glycerol may be used by the liver for gluconeogenesis, but adipocytes do not have the ability to carry out gluconeogenesis.

Answer 751

Chylomicrons are synthesized in the instant and VLDL are synthesized in the liver

Answer 752

1. An inability to secrete lipid transport lipoproteins 2. An inability to endocytose lipoproteins 3. A decreased ability to remove excess cholesterol from blood vessels While the transport and lipid binding functions of most lipoproteins are independent of apolipoprotein component, the interaction of these lipoproteins with the environment is controlled almost exclusively by apolipoproteins. Lipoproteins cannot exit or enter cells without apolipoproteins and are unable to transfer lipids without specialized apolipoproteins or cholesterol-specific enzymes.

Answer 753

High cholesterol

Answer 754

16:0 (16 carbons + no double bonds)

Answer 755

Mitochondria

Answer 756

Synthesis in the liver

Answer 757

Polyunsaturated fatty acids

Answer 758

pH (it fixes it at 7) Other conditions (temperature and concentration of reagents) are still fixed at their values from standard conditions and must be adjusted for if they are not 1 M

Answer 759

The cellular environment has a relatively fixed volume and pressure, which eliminates work from out calculations of internal energy If delta U = Q - W and W = 0, then delta U = Q

Answer 760

Yes, but only in high temperatures

Answer 761

Yes, but only in low temperatures

Answer 762

ATP hydrolysis yields about 30 kJ/mol of energy, which can be harnessed to drive other reactions forward. This may either allow a non spontaneous reaction to occur or increase the rate of a spontaneous reaction.

Answer 763

ATP is an intermediate-energy storage molecule and is not energetically dense. The high-energy bonds in ATP and the presence of a significant charge make it an inefficient molecule to pack into a spall space. Long-erm storage molecules are characterized by energy density and stable, non repulsive bonds, primarily seen in lipids.

Answer 764

Analyzing half-reactions can help to determine the number of electrons being transferred. This type of analysis also facilitates balancing equations and the determination of electrochemical potential if reduction potentials are provided.

Answer 765

NADH, NADPH, Ubiquinone (CoQ), Cytochromes, Glutathione

Answer 766

Glycolysis, fermentation, citric acid cycle, electron transport chain

Answer 767

Pentose phosphate pathway, lipid biosynthesis, bleach formation, oxidative stress and photosynthesis

Answer 768

Electron transport chain

Answer 769

Electron transport chain

Answer 770

Oxidative stress

Answer 771

Any excitable cells is maintained in a state of disequilibrium. Classic examples include muscle tissue and neurons. In addition, cell volume and membrane transport are regulated by the action of the sodium-potassium pump, which can maintain a stable disequilibrium state in most tissues.

Answer 772

RBCs Cells that rely solely on anaerobic respiration are the least adaptable to different energy sources. Therefore, red blood cells are the least flexible during periods of prolonged starvation and stay reliant on glucose.

Answer 773

During the post absorptive state, there is the greatest decrease in insulin levels. The concentrations of the counter regulatory hormones (glucagon, cortisol, epinephrine, norepinephrine and growth hormone) begin to rise.

Answer 774

Promotes glucose uptake by adipose tissue and muscles, glucose utilization in muscle cells, and macromolecule storage (glycogenesis and lipogenesis)

Answer 775

Increases blood glucose levels by promoting glycogenolysis, gluconeogenesis, lipolysis and ketogenesis

Answer 776

Increases lipolysis and amino acid mobilization, decreases glucose uptake in certain tissues and engines the activity of counterrgulatory hormones

Answer 777

Increase glycogenolysis in muscle and liver cells and increases lipolysis in adipose tissue

Answer 778

Increase basic metabolic rate and potentiate the activity of other hormones

Answer 779

Hyperthermia, tachycardia, hypertension and tachypnea

Answer 780

Glucose (except cardiac muscles prefer fatty acids)

Answer 781

Maintaining a steady-state concentration go glucose in the blood through glucose uptake and storage, glycogenolysis and gluconeogenesis Participates in cholesterol and fat metabolism, the urea cycle, bile synthesis, and the detoxification of foreign substances

Answer 782

As a person begins to exercise, the proportion of energy derived from glucose increases. This transition to almost exclusively carbohydrate metabolism will cause the respiratory quotient to approach 1.

Answer 783

No: energy expenditure, genetics, socioeconomic status, geography and other hormones also play a role in body mass regulation

Answer 784

Yes: the threshold is lower for uncompensated weight gain that it is for uncompensated weight loss. Therefore, it is easier to surpass this threshold and gain weight that to lose it.

Answer 785

= enthalpy - (temperature x entropy) | = delta H - T delta S

Answer 786

= delta G + R T ln (Q)

Answer 787

= CO2 produced / O2 consumed Estimates the composition of fuel that is actively consumed by the body

Answer 788

= mass / height^2

Answer 789

Changes in internal energy, which is equal to heat exchange within the environment

Answer 790

No, because pressure and volume remain constant

Answer 791

A measure of energy dispersion in a system

Answer 792

A mid-level energy molecule Contains high-energy phosphate bonds that are stabilized upon hydrolysis by resonance, ionization and loss of charge repulsion Provides energy through hydrolysis and coupling to energetically unfavorable reactions Can participate in phosphorylation group transfers as a phosphate donor

Answer 793

Provide useful information about stoichiometry and thermodynamics

Answer 794

One subclass of electron carriers that are derived from riboflavin (vitamin B2)

Answer 795

Vitamin B2

Answer 796

No because organisms need to harness free energy to survive

Answer 797

Insulin secretion is high and anabolic metabolism prevails

Answer 798

Insulin section decreases while glucagon and catecholamine secretion increases Observed in short-term fasting There is a transition to catabolic metabolism

Answer 799

Dramatically increases glucagon and catecholamine section Most tissues rely on fatty acids At maximum, 2/3 of the brain's energy can be derived from ketone bodies

Answer 800

Decreases blood glucose by increasing cellular uptake Increases the rate of anabolic metabolism Secreted by pancreatic beta-cells Regulated by blood glucose levels

Answer 801

Increases blood glucose by promoting gluconeogenesis and glycogenolysis in the liver Secreted by pancreatic alpha-cells Stimulated by low glucose and high amino acid levels

Answer 802

Increase blood glucose in response to stress by mobilizing fat stores and inhibiting glucose uptake Increase the impact of glucagon and catecholamines

Answer 803

Promote glycogenolysis and increase basal metabolic rate through their sympathetic nervous system activity

Answer 804

Modulate the impact of other metabolic hormones and have a direct impact on basal metabolic rate

Answer 805

It gets converted to T3

Answer 806

Responsible for the maintenance of blood glucose levels by glycogenolysis and gluconeogenesis in response to pancreatic hormone stimulation Participate in the processing of lipids and cholesterol, bile, urea and toxins

Answer 807

Stores lipids under the influence of insulin and releases them under the influence of epinephrine

Answer 808

Conservation of carbohydrates in glycogen stores and use of free fatty acids from the bloodstream

Answer 809

Anaerobic metabolism, oxidative phosphorylation (using glucose), direct phosphorylation (using creatine phosphate), or fatty acid oxidation Depends on the fiber type and exercise duration

Answer 810

Uses fatty acid oxidation in both the well-fed and fasting states

Answer 811

Consume glucose in all metabolic states, except for prolonged fasts, where up to 2/3 of the brain's fuel may come from ketone bodies

Answer 812

Calorimetry, respirometry, consumption tracking and measurement of blood concentrations of substrates and hormones

Answer 813

Leptin, ghrelin and orexin

Answer 814

No because a protonated ATP molecule contains less negative charge and therefore experiences less repulsive force

Answer 815

Hormonal controls are coordinated to regulate the metabolic activity of the entire organism, while allosteric controls can be local or systemic. Therefore, the hormonal control of glycogen is only systemic. The modification of the enzymes of glycogen metabolism by insulin and glucagon is either through phosphorylation or dephosphorylation, both of which modify covalent bonds. Therefore, the hormonal control of glycogen is systemic and covalent.

Answer 816

Resting skeletal muscles because (like adipose tissue) they require insulin for glucose uptake. Active skeletal muscles use creatine phosphate and glycogen (regulated by epinephrine and AMP) to maintain its energy requirements.

Answer 817

They increase glucose levels, causes insulin secretion

Answer 818

The body is primarily metabolizing lipids

Answer 819

The body is primarily metabolizing amino acids

Answer 820

The body is primarily metabolizing carbohydrates

Answer 821

Decreases appetite by inhibiting the production of Orexin

Answer 822

Associated with alertness

Answer 823

1000 times per day

Answer 824

1. Increase in glucagon, which accomplishes its cellular activity by phosphorylating and dephosphorylating metabolic enzymes 2. Glycogen storage is halted 3. Protein breakdown 4. Ketone bodies are used by the brain as its main energy source