Following are the statements related to mammalian chaemotaxis .
A. During chaemotaxis, the oocyte and its accompanying cumulus cells secrete molecules that attract only uncapacitated sperm toward the egg during the last stages of sperm migration.
B. These chaemotactic compound are hormone progesterone, which is made by the cumulus cells.
C. Progesterone has been shown to bind to a receptor that activates Ca2+ channels in the cell membrane of the sperm tail, leading to sperm hyperactivity and provides directional cue.
D. Cumulus cells also secrete a substance, CRISP1, that attracts sperm and hyperactivates them through CatSper channels similar as in sea urchins.
Which of  the following statement is incorrect?

TLS Online TPP Program

#Question id: 27097

#Unit 1. Molecules and their Interaction Relevant to Biology

Which of the following is correct regarding the β turns

(1) In Type I β turn i+1 lies in RHH region while i+2 lies near BS region

(2) In Type II β turn i+1 lies in BS while i+2 lies in below LHH

(3) In Type I’ β i+1and i+2 in near LHH which virtually not allowed region for most of amino acid except Gly

(4) In Type II’ β i+2 lies at 00 psi and i+1 in lower right region both i+2 and   i+1  must be Gly

TLS Online TPP Program

#Question id: 27098

#Unit 1. Molecules and their Interaction Relevant to Biology

On what positions Beta turns are characterised

TLS Online TPP Program

#Question id: 27099

#Unit 1. Molecules and their Interaction Relevant to Biology

Which of the following statement is wrong regarding the α -Turn

TLS Online TPP Program

#Question id: 27100

#Unit 1. Molecules and their Interaction Relevant to Biology

Which of the following statement is correct regarding the α -Turn and β turns

(1)In α - Turn H-bond is seen between i and i + 4 (First and Fifth residue)

(2) In α Turn conformation is based on i + 1 , i + 2 and i + 3 on the basis of this, they are classified

(3)In β turns H-bond is seen between i and i + 4 (First and Fifth residue)

(4) In β turns  conformation of i + 1 and i + 2 are crucial and on the basis of this, they are classified

TLS Online TPP Program

#Question id: 27101

#Unit 1. Molecules and their Interaction Relevant to Biology

Choose the incorrect regarding γ-turns

TLS Online TPP Program

#Question id: 27102

#Unit 1. Molecules and their Interaction Relevant to Biology

Choose the correct set of dihedral angle regarding γ-turns to avoid clashes