(Verified Update)
83 questions with answers
Topic: PCB 3134 test 1
1. do L or D amino acids make proteins
Answer: L
2. which amino acid is achiral
Answer: glycine (has H as an R group, and doesn't have an L and D form)
3. location of polar and nonpolar amino acids in proteins
Answer: polar uncharged and ionic ones are on the outer edges, nonpolar ones are in the
middle
4. how are amino acids joined
Answer: dehydration/condensation reactions connect the N and C terminus
5. protein vs polypeptide
Answer: protein implies function, polypeptide implies structure
6. monomeric vs multimeric proteins
Answer: monomeric = one polypeptide, has regulatory and catalytic subunits
7. homodimer vs heterodimer
Answer: homodimer = 2 of the same subunit heterodimer = 2 different subunits
8. structure of hemoglobin
Answer: tetramer with two alpha and two beta subunits
9. primary structure of proteins and its importance
Answer: sequence of amino acids and peptide bonds. specified by mRNA (5' to 3' matches
up with N to C), determines secondary and tertiary structure
10. secondary structure of proteins and its importance
Answer: alpha helix and beta sheet
11. secondary structure motifs
Answer: beta alpha beta, beta beta or alpha alpha hairpin loop (antiparallel)
12. why is proline a helix breaker
Answer: its nitrogen already has 3 bonds: C, R, and previous AA. it has the only R group that
loops back onto the nitrogen. this means nitrogen cannot interact with the COOof another
amino acid
13. is reflective of unique amino acid sequence because it depends on R group
interactions (both repulsion and attraction)
Answer: tertiary structure of proteins and its importance
14. disulfide bridge
Answer: cysteine-cysteine
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, 15. quaternary structure of proteins and its importance
Answer: R group interactions between polypeptides. only in multimeric structures
16. fibrous vs globular proteins
Answer: fibrous = ordered, repetitive beta sheets, extensive secondary structure
17. acidic part of a nucleic acid
Answer: PO4
18. nucleic acid functions
Answer: store, transmit, and express genetic info
19. purine vs pyrimidine
Answer: purines = A and G (two ringsa 6 and a 5)
20. AMP vs ADP vs ATP
Answer: AMP = nucleoside monophosphate (nucleotide)
21. phosphodiester bond
Answer: joins the phosphate group of one nucleotide to the hydroxyl group on the sugar of
another nucleotide
22. 5' and 3' ends
Answer: 5' phosphate, 3' sugar
23. dNTPs and NTPs
Answer: help make nucleic acid templates
24. how does RNA mimic protein structure
Answer: it makes secondary hairpin loops
25. carbohydrate functions
Answer: structure and storage
26. polysaccharide vs oligosaccharide
Answer: poly = long chain of sugars
27. aldosugar vs ketosugar
Answer: aldo = double bonded O on the end
28. examples of pentose and hexose sugars
Answer: pentose: ribose and deoxyribose
29. do cells use L or D glucose
Answer: D
30. how are monosaccharides linked
Answer: glycosidic linkagesdehydration reactions between monosaccharides
31. alpha polysaccharides
Answer: linked without flipping alternating monosaccharides (1, 4 links, and 1, 6 for
branching)
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