Use the following information to answer the question. In order to test how sea urchin sperm bind to eggs, scientists isolated the egg receptor protein

that binds to the sperm acrosomal protein called bindin. Plastic beads were coated with egg receptor for bindin (ERB1) from eggs of the sea urchin Strongylocentrotus purpuratus, and then the beads mixed with sperm from S. purpuratus or from the related species, S. franciscanus. The researchers counted how many sperm were bound to each bead. The results are shown in the graph below. Treatments:

A: S. purpuratus sperm mixed with S. purpuratus ERB1 beads

B: S. purpuratus sperm mixed with beads containing no ERB1 protein

C: S. franciscanus sperm mixed with S. purpuratus ERB1 beads

D: S. franciscanus sperm mixed with beads containing no ERB1 protein

Based on the data in the graph, which of the following conclusions is supported?

#Question id: 866

#Unit 1. Molecules and their Interaction Relevant to Biology

Which of the following is known as Sanger’s reagent

#Question id: 867

#Unit 1. Molecules and their Interaction Relevant to Biology

Match the correct diseases with their precursors

#Question id: 868

#Unit 1. Molecules and their Interaction Relevant to Biology

Which statements is incorrect about ‘The chaperonin-assisted catalysis of protein folding’

A. The non-cooperative nature of ATP binding establishes GroEL as an allosteric enzyme.

B. In GroEL with a total of 14 subunits in two heptameric rings are observed.

C. In vivo GroES is composed of seven identical subunits whilst GroEL is composed of 14 larger subunits.

D. Gro-EL being called chaperonin60 (cpn60) and Gro-ES chaperonin10 (cpn10).

#Question id: 869

#Unit 1. Molecules and their Interaction Relevant to Biology

Which statements are correct regarding protein folding

A. Many molecular chaperones were first described as heat shock proteins (Hsp) because Their rate of synthesis is increased at elevated temperatures

B. The renaturation of a denatured protein in vitro may not entirely mimic the folding of a protein in vivo.

C. Molecular chaperones are essential proteins that bind to only partially folded polypeptide chains.

D. Molecular chaperones function to lift folding polypeptides out of the false minima in their folding funnel.

#Question id: 870

#Unit 1. Molecules and their Interaction Relevant to Biology

Choose correct statements about ‘Protein Disulfide Isomerase’ in protein folding

A. Oxidized PDI catalyzes the rearrangement of a polypeptide’s non-native disulfide bonds via disulfide interchange reactions to yield native disulfide bonds.

B. Reduced PDI catalyzes the initial formation of a polypeptide’s disulfide bonds through the formation of a mixed disulfide.

C. Protein disulfide isomerase contains the conserved active site motif of Cys-Xaa-Xaa-Cys found in thioredoxin and shares a similar role to the Dsb family of proteins found in E. coli.

D. Under more reducing conditions with thiols in the active site the enzyme reshuffles disulfides (isomerase) in target proteins.

#Question id: 871

#Unit 1. Molecules and their Interaction Relevant to Biology

According to ‘Energy–entropy phenomenon’ for protein folding correct combinations of possible conformations