Chapter 6, Problem 1TYU

Choose the pair of terms that correctly completes this sentence: Catabolism is to anabolism as _______ is to_______.

1. A.    exergonic; spontaneous
2. B.     exergonic; endergonic
3. C.     free energy; entropy
4. D.    work; energy

Summary Introduction

Introduction:

Metabolism is the sum total of all the chemical reactions that occur in a cell.

Answer to Problem 1TYU

Correct answer:

Catabolism is to anabolism as exergonic is to endergonic. Therefore, option (B) is correct.

Explanation of Solution

Reason for the correct statement:

Metabolism can be of two types, catabolism or anabolism. The catabolism involves the breakdown of large molecules into smaller molecules. On the other hand, the anabolism involves the synthesis of complex molecules from smaller molecules.

The catabolism is an exergonic process as heat is released during this process while anabolism is an endergonic process as heat is required from outside during this process. Therefore, exergonic is related to endergonic in a similar way as catabolism is related to anabolism.

Option (B) is given as “exergonic; endergonic”.

“Catabolism is to anabolism as exergonic is to endergonic”, it is right answer.

Hence, the option (B) is correct.

Reason for the incorrect statements:

Option (A) is given as “exergonic; spontaneous”.

As, exergonic is opposite of endergonic and not to spontaneous, just like catabolism is to anabolism, so it is a wrong answer.

Option (C) is given as “free energy; entropy”.

As free energy is not opposite of entropy as catabolism is to anabolism, so it is a wrong answer.

Option (D) is given as “work; energy”.

As work is not opposite of energy as catabolism is to anabolism, so it is a wrong answer.

Hence, options (A), (C), and (D) are incorrect.

Conclusion

Catabolism involves release of energy while anabolism involves intake of energy.