The vertebrate brain and spinal cord start their development as a flat plate of neuroepithelial cells that folds up along most of its length to form a tube. The process of forming this neural tube is called neurulation. Which of the following signals play important role in both neurulation and cell fate patterning of neural tube?

#Question id: 451

#Unit 1. Molecules and their Interaction Relevant to Biology

The standard reduction potentials (E'°) for the following half reactions are given.

Fumarate + 2H+ + 2e– -> succinate E'° = +0.031 V

FAD + 2H+ + 2e– -> FADH2 E'° = –0.219 V

If you mixed succinate, fumarate, FAD, and FADH2 together, all at l M concentrations and in the presence of succinate dehydrogenase, which of the following would happen initially?

#Question id: 452

#Unit 1. Molecules and their Interaction Relevant to Biology

E'° of the NAD+/NADH half reaction is –0.32 V.  The E'° of the oxaloacetate/malate half reaction is –0.175 V.  When the concentrations of NAD+, NADH, oxaloacetate, and malate are all 10–5 M, the “spontaneous” reaction is:

#Question id: 453

#Unit 1. Molecules and their Interaction Relevant to Biology

Which statement does not explain why many biochemical processes are carried out via multi-step pathways rather than by single-step reactions (or only a few steps)

#Question id: 454

#Unit 1. Molecules and their Interaction Relevant to Biology

Which statement is false about most metabolic pathways?

#Question id: 455

#Unit 1. Molecules and their Interaction Relevant to Biology

Which of the following is correct for a step in a reaction pathway to serve as a control point

A) irreversible  B) endergonic  C) far from equilibrium

#Question id: 456

#Unit 1. Molecules and their Interaction Relevant to Biology

Which of the following function is done by compartmentation of enzymes?

A) helps loss by diffusion.

B) keeps separate pools of metabolites in cells.

C) can help control metabolic pathways.