Biological oxidation-reduction reactions

Question 1

What does the flow of electrons do for organisms?

Answer 1

The flow of electrons in oxidation-reduction reactions is responsible, directly or indirectly for all of the work/ energy done by living organisms

Question 2

What is photosynthesis?

Answer 2

light driven splitting of water releases electrons for the reduction of CO2 and release of O2 into the atmosphere

Question 3

How do non-photosynthetic organisms obtain energy?

Answer 3

By oxidizing products of photosynthesis, then passing electrons to atmospheric oxygen

Question 4

What is glucose oxidation?

Answer 4

electrons flow from glucose, through carrier to oxygen to form water, releasing energy

Question 5

Oxidation-reduction reactions can be described as ___________

Answer 5

Half-reactions
one is the electron donor (reducing agent)
one is the electron acceptor (oxidizing agent)

Question 6

What is dehydrogenation?

Answer 6

the loss of a hydrogen, synonymous to oxidation/ the loss of electrons.
Catalyzed by dehydrogenases

Question 7

What are the 4 ways in which electrons can be transferred?

Answer 7

-as electrons
-as hydrogen atoms
-as a hydride ion
-through combination with oxygen

Question 8

What is a reducing equivalent?

Answer 8

the transfer of one electron equivalent regardless of its form

Question 9

What is the reduction potential?

Answer 9

a redox half-reaction reduces any of the half-reactions below it in the table, only under standard conditions
If standard reduction potential is positive, reaction is spontaneous
-a measure of affinity for electrons

Question 10

Explain Catabolic + Anabolic

Answer 10

catabolic- energy releasing, oxidation- loss of electrons
anabolic- energy requiring, reduction- gain of electrons