Chapter 14 Flashcards
(31 cards)
What are redox reactions?
Oxidation = loss of electrons by a substance
Reduction = gain of electrons by a substance
What does reactions involve?
They involve the transfer of electrons from one substance to another
Are oxidation and reduction always coupled?
Yes they are , as one substance is oxidized another becomes reduced
What is an example of oxidiation and reduction?
Xe- + Y ————- X + Ye-
The x is reducing agent (gives the electron )
Th Y is the oxidizing agent (electron acceptor)
What happens in any cellular oxidation’s ?
Electrons and protons (H+) are removed at the same time
Electron travels with a proton
The removal of one proton and one electron is equivalent to the H atom
What is dehydrogenation reaction ?
The loss of an electron with the loss of one H+ proton , many enzymes that catalyze the redox reactions are called dehydrogenase
In general what does biological oxidation-reduction reactions always involve ?
They always involve 2 electrons and 2 protons (so 2 H transfer)
What happens to the H atoms ?
The H atoms don’t get released into the solution they actually are transferred to another molecule called the electron carrier
What are some electron carriers in their oxidized state?
NAD+
NADP
FAD
What is NAD+
Acts as an oxidizing agent during cellular respiration
The electrons from glucose are transferred to NAD+ and reduced to NADH
NADH then stores this energy (later used to make ATP)
How do we get energy from glucose?
Cellular respiration and fermentation
What is cellular respiration ?
Complete breakdown of glucose to CO2 and H20
What is fermentation ?
Production of various products
What is the summary equation formula for cellular respiration ?
C6H12O6 + 6H2O ——— 6CO2 + 6H2O + energy
How is the summary equation oxidized and reduced?
The C6H12O6 is oxidized to 6CO2
And then 6O2 is reduced to 6H2O
The final electron accepted is oxygen
Are electrons immediately transferred to O2
No they aren’t but transferred in a step by step process to electron carriers
What are the 3 steps of cellular respiration where do they take place?
Glycolysis (cytoplasm)
Citric acid (matrix of mitochondria)
Electron transport chain (inner membrane of mitochondrian)
What is glycolysis ?
Oxidation of glucose to pyruvic acid(pyruvate )
Occurs in cells virtually
Functions in the presence or absence of oxygen
Occurs in the cytoplasm of both eukaryotes and prokaryotes
What is the first of glycolysis ?
Glucose gets an input of energy from ATP which leaves as ADP (because bonds break in order for glucose to use that energy )and glucose becomes Glucose -6-Phosphate
What happens in the second step?
Glucose -6-Phosphate converts into Fructose -6-Phosphate
What happens at the 3rd step?
Fructose 6 phosphate gets another input of ATP (who’s bonds break and leaves as ADP) turns into Fructose 1,6-biphosphate
What happens in the 4 step?
Fructose 1,6 biphosphate splits into Glyceraladhyde 3 phosphate(G3P) and t0 DHAP
What happens in the 6 step?
G3P looses 2 electrons and 2 protons where one is released into the solution , the 2 electrons and one proton are carried by NAD+ and becomes 2NADH
Pi is also added becoming 1,3 biphosphate glycerate
What happens in the 7 step?
2 ADP is added and the bond in the 1,3 biphosphoglycerate transfers the Pi to the ADP making it 2 ATP
