University of South Florida: BIO CHEMIST 3053. Biochemistry-Gift-2-Spring-2019. All ANSWERS 100% CORRECT AID GRADE ‘A’

Old Biochem Exam 2 Biochemistry 3053 GIFT 2 Possible Questions: BLUE Possible Answers: From Previous GIFT: Yellow Highlight Notes: GREEN 1. Which enzyme is considered [REDACTED]? Part of TCA and ETC? Rate limiting: 1. Which enzyme is considered part of TCA and ETC? A. Malate dehydrogenase B. Citrate synthase C. Isocitrate dehydrogenase D. NADH- ubiquinone oxidoreductase 2. A solution at pH [REDACTED] contains a weak acid, HA. The pKa of the acid is [REDACTED]. What is the ratio of [A- ]:[HA]? pH=7 pKa=6.5 pH= pka + log ([A- ]/[HA]) 7= 6.5 + log ([A- ]/[HA]) log ([A- ]/[HA])= 0.5 ([A- ]/[HA])= 100.5 = 3.017 ratio of [A- ]:[HA]= 3.16:1 3. In mitochondria, what is the expected pH [REDACTED]? In mitochondria, what is the expected pH of the matrix compared to the intermembrane space? 4. When Compound C [REDACTED] electrons [REDACTED] Compound D, [REDACTED] When Compound C gives electrons to Compound D, then Compound D is the oxidant and Compound C is the reductant. When Compound C removes electrons from Compound D, then Compound C is the oxidant and Compound D is the reductant 5. When Compound C [REDACTED] electrons [REDACTED] Compound D, [REDACTED] When Compound C gives electrons to Compound D, then Compound D was reduced and Compound C was oxidized. When Compound C removes electrons from Compound D, then Compound C is reduced and Compound D was oxidized 6. What provides the energy to the ATP Synthase for the formation of ATP? - ADP + Pi + H+out ⇌ ATP + H2O + H+in When protons flow back down their concentration gradient (from the intermembrane space to the matrix) 7. Which of the following describe cristae? - Cristae do not have pores for movement of proteins - Their proteins are not found in outer membrane - Cristae does not seal inner membrane - Cristae does not anchor f1f0 ATP synthase - THEY INCREASE SURFACE AREA OF INNER MEMBRANE 8. (True / False) The amino acid [REDACTED] at pH 7.4 has [REDACTED] charged groups. - Amino acid T at pH 7.4 has two charged groups but net charge of 0 - Amino acid H at pH 7.4 has two charged groups but net charge of 0. - Amino acid E at pH 7.4 has two charged groups but net charge of 0 -(True / False) The amino acid [aspartic acid or glutamic acid] at pH 7.4 has [a negative (T/F) The amino acid [aspartate] at pH 7.4 has [three] charged groups T Congratulations! Due to your success in Dr. Daniel’s Biochemistry class. You have been selected by NASA to do the biochemical write up on a new organism recovered from a Martian probe! During your analysis you have discovered a brand new electron transport chain! The organism appears to use electron transport as its primary source of energy rather than ATP. This leaves you with a couple of questions to answer: During analysis, your technician reports a new electron transport chain (always check your technician’s work! Analyze this carefully!): Ickygreenone + H+ + 2e- → Ickygreenol [REDACTED] V -0.2 V Barsool → Barsoom + H+ + 2e- [REDACTED] V 0.03 V Because the reactions are not originally in the same form we would flip the bottom reaction to have the oxidized form accepting electron