Trisomy 18 is one of the most common trisomies observed in human populations. You prepare DNA samples from two unrelated infants, both with trisomy 18, and from their parents. You then type the infants and their parents for four SSRs distributed along chromosome 18:

 

                                      

In which parent did nondisjunction occur in Family 1?

TLS Online TPP Program

#Question id: 12996

#Unit 1. Molecules and their Interaction Relevant to 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

#Unit 1. Molecules and their Interaction Relevant to 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

#Unit 1. Molecules and their Interaction Relevant to Biology

Match with appropriate bonding pattern

TLS Online TPP Program

#Question id: 12999

#Unit 1. Molecules and their Interaction Relevant to 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

#Unit 1. Molecules and their Interaction Relevant to Biology

Identify the correct statement regarding the structure

TLS Online TPP Program

#Question id: 13001

#Unit 1. Molecules and their Interaction Relevant to Biology

Which of the following is incorrect 

a) antiparallel β sheets are frequently found and they are quite more stable because of more no. hydrogen bond presence and linear H bonding pattern.

b) antiparallel β sheets are frequently found and they are quite more stable because of more no. hydrogen bond presence and having distorted H bonding pattern.

c) parallel β sheets are relatively less stable and mostly found in core of protein.

d) parallel β sheets are relatively more stable and mostly found in core of protein.