Biochemistry Test for 2024 candidates provided with correct marking scheme, Exams of Biochemistry

Download Biochemistry Test for 2024 candidates provided with correct marking scheme and more Exams Biochemistry in PDF only on Docsity! Biochemistry Test for 2024 candidates provided with correct marking scheme 1. biochemistry - Correct Answers a discipline in biochemistry; is the description of molecules in biology/chemistry of proteins 2. molecular biology - Correct Answers a discipline in biochemistry; the manipulation of DNA, genetics 3. cell biology - Correct Answers a discipline in biochemistry; larger scale, functions and mechanisms within a cell/cell energetics 4. cellulose - Correct Answers a natural polymer; found in plants for storage 5. glycogen - Correct Answers a natural polymer; found in animals for storage 6. protein - Correct Answers a natural polymer; tightly linked bonds 7. nucleotide - Correct Answers a natural polymer; covalent bonds 8. C,H,N,O,S - Correct Answers chemical elements commonly found in biochemistry 9. carbon - Correct Answers an element commonly found in biochemistry, creates strong single or double bonds with very little rotation 10. covalent - Correct Answers a chemical bond in biology; a pair of shared electrons, very strong, bonds between polymers, >1 bond per atom, flexible and alternate re- arrangement 11. non-covalent - Correct Answers a chemical bond in biology; weaker bonds, but additive, creates specificity, highly dynamic/transient bonds, required for molecular recognition 12. electrostatic, hydrogen, van der wails, hydrophobic - Correct Answers 4 types of non-covalent interactions 13. electrostatic - Correct Answers a non-covalent interaction; such as ionic bonds Na⁺ + Cl⁻ -> Nalco 14. hydrogen - Correct Answers a non-covalent interaction; a H is shared between two electronegative atoms such as F,O, or N; the more electronegative atom pulls the electron closer, creating a dipole 15. donor acceptor - Correct Answers the H bond _____ becomes more tightly linked, the H bond_____becomes less tightly linked (two answers separated by a space please) 16. Van Der Waals - Correct Answers a non-covalent interaction; the interaction between molecules with temporary dipoles from fluctuating electrons, are weak but additive 17. hydrophobic interaction - Correct Answers a non-covalent interaction; the clustering of these molecules in polar substances i.e. water interacts with itself and causes other non-polar residues to cluster 18. biological solvent - Correct Answers roles of water; many organic and biological materials are able to dissolve in water 19. part of reaction - Correct Answers roles of water; water is a common substance in biochemical reactions such as the cleavage of bonds 20. regulation - Correct Answers roles of water; water is essential in regulating temperature and pH (the ideal temperature of water with the highest heat capacity is 37°C) 21. water - Correct Answers a substance found in nearly all biological reactions and organisms; has a bond angle between H's of 104.5°, has a dipole, H-bonds with itself, cohesive and dissolves polar or charged compounds 22. hydrophilic - Correct Answers water as a solvent; types of bonding in water "loving" compounds are dipole-dipole, H-bonding, and dipole-ion 54. 9.7 - Correct Answers the amino Pak 55. 7 - Correct Answers the pH if the R-group has no net charge. i.e. charge is 0 56. equivalence - Correct Answers the point on a titration curve where the [zwitterion] concentration is the highest 57. structure - Correct Answers during AA titrations, the ______ of the AA changes 58. Isoelectric pH - Correct Answers defined as the pH were the structure of an AA or peptide has no net charge; the average of the Pak’s 59. cysteine - Correct Answers oxidized S-S bonded aa usually outside the cell 60. cysteine - Correct Answers reduced S, single cysteine usually found inside the cell 61. histidine - Correct Answers an AA that usually regulates the active sites of an enzyme in response to pH 62. condensation - Correct Answers the name of the reaction when 2 AA's join their amino and carboxyl terminus (water is removed) 63. multiple - Correct Answers 1 to 10 AA's together 64. polypeptide - Correct Answers 10 to 100 AA's together 65. protein - Correct Answers greater than 100 AA's together 66. residue - Correct Answers another name for the side chain of an AA 67. left right - Correct Answers directionality of drawn peptides; ______side is the N terminus, ______side is the C terminus (two answers please, separated by a space) 68. hydrolysis - Correct Answers the name of the reaction when 2 AA's break their amino and carboxyl terminus (water, 6M Hall and heat are added) 69. peptidases - Correct Answers specialized proteins that break peptide bonds (trypsin and chymotrypsin are examples) 70. 1 AMU - Correct Answers equivalent mass of 1 Da (Dalton) 71. 110 DA - Correct Answers the average mass of an AA 72. monomeric - Correct Answers protein composition; protein consists of a single polypeptide chain 73. multisubunit - Correct Answers protein composition; same as oligomeric; protein consists of two or more polypeptide chains (chains can be identical or different) 74. oligomeric - Correct Answers protein composition; 2 or more polypeptide chains together 75. subunit - Correct Answers protein composition; single pieces of a multisubunit protein 76. simple - Correct Answers protein composition; a protein is said to be this if it is only composed of AA's (no other groups) 77. conjugated - Correct Answers protein composition; a protein is said to be this if it contains AA's and other chemical groups (such as organics or metal ions) 78. prosthetic group - Correct Answers protein composition; names of non AA groups found on conjugated proteins, cofactors/coenzymes covalently linked to protein 79. globular - Correct Answers protein composition; a protein is said to be this if it is water soluble and found in the cytoplasm of cells 80. fibrous - Correct Answers protein composition; a protein is said to be this if it is water soluble and found in the cell structure 81. assay development - Correct Answers first step in protein isolation and purification 82. source and lyse - Correct Answers second step step in protein isolation and purification 83. fractional centrifugation - Correct Answers a protein isolation technique that separates the supernatant from the pellet 84. supernatant - Correct Answers the liquid component left from a fractional centrifugation 85. pellet - Correct Answers the more solid component separated from a fractional centrifugation 86. chromatography - Correct Answers a protein isolation technique that separates proteins based on many characteristics 87. gel filtration or molecular exclusion - Correct Answers a method of chromatography; separation based on size, large proteins elute first, small proteins elute later, 88. ionic exchange - Correct Answers a method of chromatography; separates proteins based on charge (PI); gel is usually agarose or cellulose 89. affinity chromatography - Correct Answers a method of chromatography; separation based on ligand attachment; protein attaches to ligand in gel; excess ligand is then poured in, eluting the protein (due to entropic processes) 90. HPLC - Correct Answers a method of chromatography; separation based on hydrophobic interactions, works well with peptides, resin is small, slow flow, high pressure 91. specific activity - Correct Answers total activity/total protein 92. Yield - Correct Answers total activity(current)/total activity(original) 93. purification level - Correct Answers specific activity(current)/specific activity(original) 94. SDS-PAGE - Correct Answers a gel used to determine the molecular size and purity of a protein, smaller proteins migrate faster, charge does not matter, blue dye stains basic residues 95. SDS - Correct Answers sodium dodecyl sulfate, a negatively charged detergent used to coat proteins in molecular size and weight assay (used with PAGE) 96. PAGE - Correct Answers polyacrylamide gel electrophoresis, gel used in molecular size and weight assay (used with SDS) 121. beta barrel - Correct Answers a super secondary structure; parallel beta strands connected with an alpha helix 122. collagen - Correct Answers a super secondary structure; a fibrous protein that contains a triple helix(super helix) high in proline and hydroxyproline, a non- conventional helix 123. early events - Correct Answers first part of the protein folding pathway; the formation of secondary structure 124. intermediate - Correct Answers second part of the protein folding pathway; formation of ionic bonds 125. final - Correct Answers last part of the protein folding pathway; compaction of the protein 126. in vivo - Correct Answers a biological process that occurs in its natural environment 127. molecular chaperone - Correct Answers a folding accessory protein; binds unfolded proteins by "sheltering" exposed non-polar regions 128. heat shock protein - Correct Answers a folding accessory protein; ensures that proteins do not de-nature at high temperatures 129. heat, organic solvents, SDS, urea - Correct Answers the 4 causes of protein unfolding 130. denaturation - Correct Answers the loss of protein function (as well as structure), can be renatured "in vitro" 131. homotypic - Correct Answers a protein in which all the subunits are the same 132. heterotypic - Correct Answers a protein in which the subunits are different 133. 141 - Correct Answers the number of AA's on one alpha chain in hemoglobin 134. 144 - Correct Answers the number of AA's on one beta chain in hemoglobin 135. protoporphyrin - Correct Answers a prosthetic group (polyp role ring) that binds Fe, has 4 bonding points 136. 6 - Correct Answers the number of bonding points that Fe requires 137. Histidine F8 - Correct Answers interacts with Fe in hemoglobin 138. Histidine E7 - Correct Answers shields the Fe in hemoglobin in the +2 state of oxygen uptake 139. hemoglobin - Correct Answers an oxygen carrying molecule, forms a sigmoidal oxygen binding curve, found in the vascular system, 50% saturation @ 3kPa 140. myoglobin - Correct Answers an oxygen carrying molecule, forms a hyperbolic oxygen binding curve, found in the musculature for uptake, 50% saturation @ .2kPa 141. allosteric interaction - Correct Answers the binding of one site affects binding at another site 142. the boar effect - Correct Answers the co-operative binding of hemoglobin and its dependency on protons and carbon dioxide concentrations (allosteric effectors) 143. deoxy - Correct Answers the T(tense) state of hemoglobin, central cavity is larger 144. oxy - Correct Answers the R(relaxed) state of hemoglobin, central cavity is smaller 145. tent - Correct Answers the physical form hemoglobin helix assumes when in the unbound state 146. linear - Correct Answers the physical form hemoglobin helix assumes when in the bound state 147. 2,3-BPG - Correct Answers a molecule present in high concentrations in RBC, binds to the T state of Hob, and allows for the better release of all oxygen molecules, is an allosteric effector, negatively charged 148. gamma - Correct Answers found in fetal Hob, replaces the two beta subunits, difference between the beta is that it has a serine at 143 instead of a histidine, higher affinity for oxygen than maternal Hob 149. sickle cell anemia - Correct Answers a Hob mutation; a mutation from Glu6-- >Val in the beta subunit decreases the solubility, causing fibrous aggregations 150. thalassemia - Correct Answers a Hob mutation; the loss or substantial reduction of a single Hob chain 151. alpha thalassemia - Correct Answers a Hob mutation; no alpha subunits in Hob, 4 beta subunits (Hahn) 152. beta thalassemia - Correct Answers a Hob mutation; no beta subunits, 4 alpha subunits; this condition is more common 153. immunoglobulin - Correct Answers structures involved in immune response 154. IgG - Correct Answers an immunoglobulin that is most common 155. IgA - Correct Answers an immunoglobulin that is usually found in secretions (such as saliva) 156. Inge - Correct Answers an immunoglobulin that is usually related to allergenic responses 157. 12 - Correct Answers the number of domains in IgG 158. variable region - Correct Answers a region on an antibody that changes, allowing the recognition of different antigens 159. constant region - Correct Answers a region on an antibody that does not change 160. hypervariable loop - Correct Answers a structure found in the beta chains of immunoglobulin folds that allows for the recognition of different antigens 188. reversible - Correct Answers enzymatic inhibition; non-covalent bonding effectors stop enzymatic processes, the three general forms are competitive, non- competitive (pure and mixed), and uncompetitive 189. competitive - Correct Answers enzymatic inhibition; where the effector resembles the substrate, binds to the active site, high [S] lessens the effect of the inhibitor, Vmax stays the same, Km is altered 190. pure non-competitive - Correct Answers enzymatic inhibition; inhibitor and substrate bind to different sites; Km stays the same, Vmax changes 191. mixed non-competitive - Correct Answers enzymatic inhibition; inhibitor and substrate bind to different sites; Vmax and Km changes 192. uncompetitive - Correct Answers enzymatic inhibition; inhibitor binds to the ES complex, Km decreases and Vmax increases, locks the substrate in position 193. allosteric - Correct Answers regulatory pathways are usually controlled by these class of enzymes; in addition, the first enzyme in the pathway is usually the regulatory one and of this type 194. allosteric - Correct Answers in enzymes, binding or catalytic changes cause a conformational change elsewhere 195. homotopic - Correct Answers enzymatic allosteric; where the substrate and the effector molecule are identical 196. heterotrophic - Correct Answers enzymatic allosteric; where the substrate and the effector are different 197. MWC concerted model - Correct Answers allosteric regulation; enzymes can either be found in the TT or RR state, the effector molecule shifts the enzyme to one state (hybrid TR not possible) 198. sequential model - Correct Answers allosteric regulation; enzymes can either be found going from TT->TR->RR, the TR hybrid is possible 199. covalent modification - Correct Answers cellular enzyme regulation; modification via phosphorylation of Seer, Thru, Tyr or ubiquitination of Lys 200. proteolytic cleavage - Correct Answers cellular enzyme regulation; some enzymes are synthesized in the inactive form, the zymogen is cleaved into the active state, this is an irreversible process 201. isoenzyme - Correct Answers cellular enzyme regulation; enzymes that carry out the same reaction but have different kinetics, regulatory properties, forms of coenzymes, and distribution 202. zymogen - Correct Answers cellular enzyme regulation; the term used to describe an enzyme formed in an inactive state that has to be cleaved in order to work