TLS Online TPP Program

#Question id: 19914


In aerobic yeast fermentation for production of citric acid from alkanes using a fed-batch culture, why alkanes are slowly fed to the yeast?

#Section 5: Bioprocess Engineering and Process Biotechnology
  1. Citric acid is toxic to the cells
  2. Alkanes cause foaming
  3. Fast addition of alkanes will inhibit the cells and reduce oxygen transfer rates
  4. Fast addition of alkanes will cause the cells to grow too quickly
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TLS Online TPP Program

#Question id: 12995

#Section 2: General Biology

Which of the following constraints affect the stability α-helix, 
a) the intrinsic propensity of an amino acid residue to form an α-helix.
b) the interactions between R groups.
c) the bulkiness of adjacent R groups.
d) the occurrence of Pro and Gly residues.

TLS Online TPP Program

#Question id: 12996

#Section 2: General Biology

Which of the following is incorrect regarding to α-helix
a) In the α helix, the first four NH groups and last four CO groups will normally lack backbone  hydrogen bonds.
b) the length of an amino acid in α-helix reduced almost 3 times than linear structure.
c) the frequent occurrence of Pro and Gly residues favour α-helix formation.
d) dihedral (ϕ and ψ) angle should be close to -57 and -47.

TLS Online TPP Program

#Question id: 12997

#Section 2: General Biology

Which of the given reason is correct to minimize the repulsion in an α-helix
a) positively charged amino acids are often found near the amino terminus of the helical segment
b) negatively charged amino acids are often found near the amino terminus of the helical segment
c) positively charged amino acids are often found near the C-terminus of the helical segment.
d) negatively charged amino acids are often found near the C-terminus of the helical segment.

TLS Online TPP Program

#Question id: 12998

#Section 2: General Biology

Match with appropriate bonding pattern

TLS Online TPP Program

#Question id: 12999

#Section 2: General Biology

Proline and glycine both disturb the symmetry of α-helix which of the following are true regarding to these two amino acids
a) proline changes the orientation of hetropolymeric α-helix hence proline can be placed only as 1st amino acid residue near to C-terminus 
b) proline changes the orientation of polymeric α-helix hence proline can be placed only as 1st amino acid residue near to N-terminus
c) glycine disrupts the heteropolymeric α-helix by changing the helicity.
d) homopolymer of proline and glycine can form stable helix. 

TLS Online TPP Program

#Question id: 13000

#Section 2: General Biology

Identify the correct statement regarding the structure