Extinction is a natural phenomenon. It is estimated that 99% of all species that ever lived are now extinct. Why then do we say that we are now in a biodiversity crisis?

#Question id: 48

#Unit 1. Molecules and their Interaction Relevant to Biology

Which of the following statements regarding enantiomers true?

#Question id: 49

#Unit 1. Molecules and their Interaction Relevant to Biology

The equilibrium constant, Keq, for the following reaction is 2 × 105 M: If the measured cellular concentrations are [ATP] = 5 mM, [ADP] = 0.5 mM, and [Pi] = 5 mM, on the basis of the above information calculate the Keq in living cells?

#Question id: 50

#Unit 1. Molecules and their Interaction Relevant to Biology

The enzyme fumarase catalyzes the reverse hydration of fumaric acid to l-malate, but it will not catalyze the hydration of maleic acid, the cis isomer of fumaric acid. This is an example of:

#Question id: 51

#Unit 1. Molecules and their Interaction Relevant to Biology

 If the equilibrium constant, Keq, for the reaction ATP → ADP + Pi is 2.22 × 10⁵ M, calculate the standard free-energy change, ΔG°, for the synthesis of ATP from ADP and Pi at 25 °C.

#Question id: 52

#Unit 1. Molecules and their Interaction Relevant to Biology

Choose the incorrect option regarding Isomerism.

#Question id: 53

#Unit 1. Molecules and their Interaction Relevant to Biology

Calculate the number of times the DNA of a modern E. coli cell has been copied accurately since its earliest bacterial precursor cell arose about 3.5 billion years ago. Assume for simplicity that over this time period, E. coli has undergone, on average, one cell division every 12 hours (this is an overestimate for modern bacteria, but probably an underestimate for ancient bacteria).