This review sheet will be graded for completeness meaning that you earn 5points for submitting it on Moodle by Sunday night The answer key is already posted on Moodle so you can check your answers after you complete it This review does not cover everything that will be on the test and some things covered in this review may not be on the test 1 Which of the following can NOT easily diffuse through a phospholipid bilayer Select all the apply Explain why a H hydrogen ions charged ions wouldn t be able to easily diffuse b c Sugars large and not easily diffusible slow rate Sodium ions charged can t diffuse d O2 only one that can easily diffuse e ATP phosphates are charged f A protein made up of many serines and glutamines proteins are too large to diffuse 1 True or false regarding the lac operon In the lac operon when both glucose and lactose are present in high concentrations you would expect to find select true or false for each of the following statements High levels of CAP cAMP bound at the positive control binding site on the DNA F The repressor protein would be bound at the operator site F The lacI would not be expressed because of the high lactose concentrations F RNA polymerase would be bound to the promoter and would be actively transcribing the lacZ and lacY genes T 1 How many molecules of water were produced from the reactions that created this polypeptide 2 H20 molecules 1 Explain what would happen to lacZ and lacY expression if there were a mutation in the operator site such that the repressor protein was unable to bind under the following sets of conditions a High lactose low glucose High rates of gene expression b No lactose high glucose slower expression of gene expression 1 The sequence below shows part of an mRNA transcript the start codon is not shown but it exists Where would you expect this section of the protein to be located in a cytosolic protein Explain you answer in 1 2 sentences 5 CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC 3 Nonpolar on the inside True or false regarding protein folding 1 Arginine at physiological pH that is normal can participate in ionic bonding with either glutamic acid or aspartic acid T Threonine and serine can form hydrogen bonds with one another or water molecules T Only polar amino acids can be in an alpha helix because hydrogen bonds hold secondary structure together F 1 First transcribe then translate the coding sequence below Assume the frame begin with the first codon Then create a mutation that leads to a negative charge increase on this peptide while decreasing its hydrophobicity Decide what to mutate and show how it would change the DNA sequence and the protein sequence Template 5 GGT CCT CAC AGC CAT 3 Transcription 5 AUG GCU GUG AGG ACC 3 Translation Met Ala Val Arg Thr Mutant Protein Met Asp Val Arg Thr Mutant DNA 5 GGT CCT CAC UAG CAT 3 1 This is the overall reaction for photosynthesis We can estimate that G 686 kcal mol 6CO2 6H2O C6H12O6 6O2 a b If you mixed the reactants in a test tube would this reaction occur spontaneously Explain your answer in 1 2 sentences No it wouldn t occur spontaneously but it would happen with energy Is there more free energy in the reactants or the products Products Read the following information about protein folding and Alzheimer s Then answer the questions Alzheimer s disease is a chronic neurodegenerative disease that usually starts slowly and worsens over time People with Alzheimer s experience memory loss and impairments to other important mental functions Most Alzheimer s occurs in the elderly but about 1 2 million of the 5 million people who develop dementia or Alzheimer s each year are under 65 Approximately 5 of Alzheimer s is caused by inherited dominant mutations People with the mutation develop symptoms much earlier than typical age 51 Some of these mutations are changes in the amino acids in the APP protein The biology and biochemistry of Alzheimer s disease is still not well understood and there is a lot of current research focused on finding the cause of and treatments for Alzheimer s disease APP amyloids and Alzheimer s disease amyloid precursor protein APP is a large membrane protein that normally plays an essential role in neural growth and repair It is found in nerve cells neurons It is 695 amino acid long amyloids are APP fragments that are composed of 28 amino acids Ubiquitin mediated proteolysis marks proteins for destruction by first tagging the protein with ubiquitin and then proteases enzymes that break peptide bonds by hydrolysis break down the tagged protein into amino acids This process removes proteins when they are no longer needed amyloids are small fragments of APP Plaques form when amyloids clump together amyloids are chemically sticky the fragments stick together and gradually builds up into plaques These plaques damage nerve cells which may explain the memory damage associated with Alzheimer s 1 Compare these two peptide sequences how are the two polypeptides different There is a PHE inserted for the His in the mutant amyloid Asp Ala Glu Phe Arg His His Ser Gly Tyr Glu Val His His Mutant amyloid Asp Ala Glu Phe Arg His Phe Ser Gly Tyr Glu Val His His a What level of protein structure is shown above Primary protein structure protein to change shape 1 Unmutated and mutant amyloid have very different shapes Why could changing one amino acid cause the whole The proteins would not be able to form the same way with some being hydrophobic instead of hydrophilic 1 APP is transmembrane protein List 2 amino acids which you would expect to find in the intra membrane region of this protein facing the fatty acid tails of the plasma membrane List 2 amino acids which you would expect to find in the extracellular facing region of this protein Leucine isoleucine 1 Mutant amyloids have the amino acid phenylalanine at position 717 rather than histidine Mutant amyloid fragments stick together which causes plaques to form which can lead to Alzheimer s Explain why a mutation that changes histidine to phenylalanine may cause plaques to form more easily Instead of having the charged histadine it is replaced with non polar phenylalanine Phenylalanine will clump together other hydrophobic amino acids Ionic bonds form between ions that are oppositely charged The following bonds are important in protein formation and folding Describe each type of bond 1 a Hydrogen bonds form between a hydrogen atom with a positive charge and a negatively charged atom b c Hydrophobic interactions aka