Life at the molecular level

Question 1

Briefly describe life processes in terms of the Laws of Thermodynamics

Answer 1

Energy can be converted from one form to another, but not created or destroyed.
All energy transformations ultimately lead to more entropy in the universe.
This is true for living organisms, even though the processes create more order, the heat created is released into the universe, creating more entropy there.

Question 2

Explain that life processes occur in a dynamic steady state

Answer 2

In biological reaction pathways, products from one, are used in the next pathway, and so are unable to reach equilibrium. Food is supplied and waste is removed in a continuous state.
This is called a “Dynamic Steady State”. It allows the entropy produced to be used in the construction of higher-order compounds.

Question 3

Define Metabolism

Answer 3

Metabolism – The chemical processes in a living organism that allows food to be used for tissue growth.
It is a mix of summative and degradative reactions (Anabolism and catabolism respectively.)

Question 4

Define Anabolism

Answer 4

Anabolism- Occur with +ve G, are not spontaneous.

Question 5

Define Catabolism

Answer 5

Catabolism – Occur with -ve G, are spontaneous.

Question 6

How do anabolic and catabolic reactions work together?

Answer 6

Energy obtained from catabolic reactions is used up in anabolic reactions to produce more highly ordered compounds.

Question 7

Describe, in general terms, the structures and contributions to metabolic flow of ATP, ADP, NADP, NAD, FAD.

Answer 7

ATP/ADP acts as a free energy carrier, coupling anabolic and catabolic reactions using phosphate group transfers.

NADP/NAD and FAD are used in redox reactions as electron carriers.