Chapter 5 Flashcards
Reduction reaction involves _____
Gain of electrons
Oxidation reaction involves _____
Loss of electrons
What are catabolic processes?
BReakdown of larger molecules to produce energy
What are anabolic processes
Synthesis of larger molecules from smaller ones
______ consumes sugars less efficiently than respiration in an attempt to produce energy
Anaerobic Fermentation
ATP molecules have 3 phosphate groups, therefore ADP molecules have ____
2 phosphate groups
What does the ADP/AMP to ATP ratio indicate to the cell?
If there is a lot of ADP/AMP in relation to ATP, the cell does not have much energy left to synthesize proteins
What is the function of the kinase AMPK?
Recognizes the ratio of ADP/AMP to ATP, and halts protein synthesis if energy levels are low
Briefly describe the appearance of the mitochondria
HAs an inner and outer membrane, and the inner space is divided into matrix and intermembrane space, Finger-like projections inside the mitochondria are referred to as Cristae.
Why do mitochondria require DNA?
They must synthesize their own proteins
TRUE OR FALSE: Mitochondria are not capable of fusing or splitting
FALSE!! Some cells have multiple mitochondria and therefore they must be able to split to create more
TRUE OR FALSE: Mitochondria are passed down from our mothers
TRUE
How is the lipid (and otherwise) composition of the mitochondrial membrane so significant?
IT is the same lipid composition as bacterial membranes, and contained a bacterial pore-forming protein called “porin”
What is present in the mitochondrial matrix?
Circular DNA molecule, ribosomes, enzymes, sometimes RNA/proteins
What kind of reaction is it when NAD+ is converted to NADH?
Reduction
Glycolysis is the breakdown of 6 carbon Glucose to 3 carbon ______
Pyruvate
After glycolysis, pyruvate is converted to Acetyl CoA. How does this occur?
By release of Co2 (decarboxylation) and a hydrogen (converting NAD+ to NADH)
What happens to Pyruvate in aerobic conditions, anaerobic (muscle) conditions, and anaerobic (bacterial) conditions?
Aerobic - Transported to mitochondrial matrix and oxidized to CO2 and H2O Anaerobic (muscle) - Reduced to lactate in 1 step Anaerobic (bacterial) - Reduced to ethanol in 2 steps (pyruvate > acetaldehyde > ethanol)
What does TCA Cycle stand for?
Tricarboxylic acid cycle
What is generated from TCA cycle? What are the equivalent amounts in ATP?
3 NADH, 1 FADH2, 1 GTP (ATP)
NADH - 3 ATP
FADH2 - 2 ATP
So, 15 ATP x 2!
How is NADH transported to ATP?
Via Oxidative Phosphorylation: NADH transfers its high energy hydrogen molecule to oxygen, creating water. This creates a high energy proton gradient that causes phosphorylation of ADP into ATP
What happens to the one NADH produced during glycolysis?
NADH cannot enter the mitochondria alone, but instead needs a Glycerol phosphate shuttle
How does the Glycerol phosphate shuttle work?
Dihydroxyacetone phosphate takes an H+ from NADH (converting it to NAD+), becoming GLycerol 3 - phosphate. This is the form that can enter the intermembrane space.
Once inside, the H+ from Glycerol-3 -Phosphate is transferred to FAD ( a reaction catalyzed by glyverol 3 - phosphate dehydrogenase), creating FADH2. This dihydroxyacetone phosphate moves back across the outer cel membrane
Describe chemiosmosis
As electrons move through the electron-transport chain, H+ ions are pumped out across the inner membrane, and ATP is formed by H+ ions moving BACK into the mitochondria via the ATP synthase enzyme.