In light reaction, the funneling of excitation from the antenna system toward the reaction centre has been shown,

a.) The excited-state energy of pigments increases with distance from the reaction centre; that is, pigments closer to the reaction centre are lower in energy than those farther from the reaction centre

b.) The energy gradient ensures that excitation transfer toward the reaction centre is energetically favorable and that excitation transfer back out to the peripheral portions of the antenna is energetically unfavourable

c.) Some energy is lost as heat to the environment by this process, but under optimal conditions almost all the excitation energy absorbed in the antenna complexes can be delivered to the reaction centre

d.) The excited-state energy of  pigments decreases with distance from the reaction centre

Which of the following above combination is true?

#Question id: 4234

#Unit 3. Fundamental Processes

Accuracy in the translation of mRNA into the primary structure of a polypeptide depends on specificity in the __.

#Question id: 4235

#Unit 3. Fundamental Processes

What would be the consequence of a mutation in a bacterial cell that produces a defective aminoacyl-tRNA synthetase that attaches a lysine instead of the normal phenylalanine to tRNAs with the anticodon AAA?

#Question id: 4236

#Unit 3. Fundamental Processes

In bacteria, there are 61 mRNA codons that specify an amino acid, but only 45 tRNAs. Which of the following statements explains this fact?

#Question id: 4237

#Unit 3. Fundamental Processes

A part of an mRNA molecule with the following sequence is being read by a ribosome: 5′-CCGACG- 3′ (mRNA). The following charged transfer RNA molecules (with their anticodons shown in the 3′ to 5′ direction) are available. Two of them can correctly match the mRNA so that a dipeptide can form. Which of the following dipeptides will form from this mRNA?

#Question id: 4238

#Unit 3. Fundamental Processes

Use the following information to answer the question. A part of an mRNA molecule with the following sequence is being read by a ribosome: 5′-CCGACG- 3′ (mRNA). The following charged transfer RNA molecules (with their anticodons shown in the 3′ to 5′ direction) are available. Two of them can correctly match the mRNA so that a dipeptide can form.

#Question id: 4239

#Unit 3. Fundamental Processes

Use the figure to answer the question. What type of bonding is responsible for maintaining the shape of the tRNA molecule shown in the figure?