The 3D structure of the complete Escherichia coli ribosome with bound mRNA and tRNAs revealed that the very amino terminus of one protein (L27) does reach into the active site. This finding suggested a role for this protein in catalysis. To test this possibility, the nine amino acids at the L27 amino terminus that were in close proximity to the active site were eliminated by mutation. The following possible outcomes were found to be correct as

A. The resulting cells produced ribosomes with reduced but detectable peptidyl transferase activity

B. Region of the L27 protein contributes to peptidyl transferase activity

C. The mutant ribosomes, didn’t synthesised wildtype levels of cells

D. Vast majority of this increase in peptide bond formation is retained, even without the presence of L27 in the active site

E. The most likely role for L27 is to correctly position one or more of the RNA components of the active site

#Question id: 5133

#Unit 5. Developmental Biology

Identify the correct ligands in both receptor serine kinase pathway.

#Question id: 5134

#Unit 5. Developmental Biology

Match the following cleavage patterns with the species in which they occur.

#Question id: 5135

#Unit 5. Developmental Biology

In xenopus, result of tissue transplantation during early and late gastrulae

(A) Cells of early newt gastrula exhibit conditional development.

(B) Cells of early newt gastrula exhibit autonomous development

(C) Cells of late newt gastrula exhibit conditional development.

(D) Cells of late gastrula exhibit autonomous development.

The correct inferences are:

#Question id: 5136

#Unit 5. Developmental Biology

Some statements regarding to hippo pathway.

A. The Hippo signal transduction pathway have a dedicated ligand or receptor

B. Hippo stands for one of several important kinases that are critical for organ size control

C. It was first identified in Drosophila, where its loss resulted in a “hippopotamus”-shaped phenotype due to excessive growth

D. Gain of Hippo causes cells to divide significantly faster while slowing apoptosis

E. overexpression of its main transcriptional effector, Yorkie causes cells to divide significantly faster while slowing apoptosis

Which of the following combination are incorrect?

#Question id: 5137

#Unit 5. Developmental Biology

Match the correct animal and their mechanism of germplasm specification.

#Question id: 5138

#Unit 5. Developmental Biology

When presomitic mesoderm (PSM) that would ordinarily form thoracic somites is transplanted into a region in a younger embryo (caudal to the first somite) that would ordinarily give rise to cervical (neck) somites, the grafted mesoderm differentiates according to its original position and forms ribs in the neck. This phenomena is called as: