Lecture 10 - ENERGY GENERATION- incomplete Flashcards
Is Glycolisis an anaerobic or aerobic reaction?
Anaerobic, it does not require oxygen.
What is the difference between anaerobic and aerobic respiration?
Anaerobic respiration does not require oxygen. Aerobic does require oxygen and produces CO2 as a byproduct.
What is the most significant difference between eukaryotes and prokaryotes?
Eukaryotes use aerobic respiration to generate ATP.
What is glycolysis?
An anaerobic enzymatic cascade that produces pyruvate and a very little ATP. (glycolysis produces only 1 ATP for every 19 ATP generated via aerobic respiration)
True or False: Chlorophyll is a porphyrin?
TRUE; it carries Magnesium
What is the importance of chlorophyll?
possible the most important molecule on earth for maintaining life. it generates oxygen and consumes carbon dioxide.
The two primary sources of fuel for aerobic respiration are glycolysis and ß-Oxidation. What do each of these metabolize?
glycolosis - sugars
ß-oxidation - fatty acids
glycolysis produces how many pyruvic acids (pyruvate), how many NADH and how many ATP?
2 pyruvic acid
2 NADH
2 ATP
What is the result of ß-oxidation?
fatty acids metabolized and attached to coenzyme A to become ACA - acetyl coenzyme A
The mitochondrion is made up of an inner membrane and an outer membrane. What are the primary anatomical features of the inner and outer membranes?
Outer Membrane - Porins - allow molecules to pass in and out of the mitochondrion selectively.
Inner Membrane - inter-membrane space, cristae - invaginations within the continuous inner membrane.
True or false: the mitochondrion has its own DNA?
true: they allow the mitochondrion to synthesize proteins.
Why do mitochondrion float freely with in the cell?
They move around to consume product (starches, sugars, ions) they need to produce cellular energy.
The mitochondrion has evolved to create a concentration gradient between the matrix and the inter-membrane space, within its own structure. What is the purpose of this concentration gradient?
The inter-membrane space forms the “battery” which stores the energy potential. The goal of the Electron Transport System (step 3 of Aerobic Respiration) is to fill the inter-membrane space with H+ ions in high concentration. This potential energy (concentration gradient of H+) will be utilized to power the manufacture of ATP.
What molecule is concentrated in the inter-membrane space of the mitochondrion?
Hydrogen ions (H+) which is really just a Hydrogen proton.
Mitochondrion require a plethora of molecules to generate energy for the body. What are four common and important enzymes found imbedded in the cristae?
cytochrome P45o series
Coenzyme Q10
ATP synthase
all are transported across the outer membrane’s porins through specialized transport mechanisms (channel proteins etc)
Why does the mitochondria carry loops of DNA in the matrix to code for the enzymes and proteins needed in ß-oxidation, glycolysis, the Krebs cycle and oxidative phosphorylation?
to conserve the genes in the nucleus from having to constantly be unzipped, as the production of ATP by mitochondrial enzymes is voluminous.
What is the level of Oxidative stress in the mitochondrial matrix?
very high - oxidative stress regularly wears out the proteins of the mitochondrion.
What are the four steps of Aerobic Respiration and where does this activity take place?
- Pyruvate Decarboxylation (glucose only)- matrix of the Mitochondrion
- Krebs Cycle (citric acid cycle) - matrix
- Electron Transport Chain - cristae of the mitochondrion
- ADP to ATP phosphorylation - cristae
What are the results of Aerobic respiration?
massive generation of ATP
What is ATP used for?
- driving enzymatic catalysis
- driving membrane transport of proteins
- driving molecule and macromolecule manufacture (anabolism)
Pyruvate Decarboxylation takes place in the matrix of the mitochondrion. What is consumed and what is produced?(in an extremely simplified way)
consumes: pyruvate
produces: Acetyl Coenzyme A (which enters the Krebs Cycle), CO2, and 1 NADH
Krebs Cycle (or Citric Acid Cycle) takes place in the matrix of the mitochondrion. What is consumed and what is produced? (in an extremely simplified way)
consumed: carbon is “burned” (using Acetyl Coenzyme A)
produced: energy carrier molecules (NADH & FADH2 among others)
The Electron Transport Chain (ETC) is lodged in the cristae of the mitochondrion. In an extremely simplified way, what is happening in this chain?
Energy carrier molecules produced from the Krebs Cycle move electrons to power a build-up of potential energy in the mitochondrion to create a battery of energy.
How is the energy potential built up in the mitochondrion utilized in Oxidative Phosphorylation or ATP Synthase Phosphorylation?
the H+ built up in the inter membrane space after the Electron Transport Chain wants to equilibrate. They are funneled through a transport channel in the cristae membrane that contains the enzyme ATP Synthase - the energy produced allows the high energy phosphorous bond that characterizes ATP to occur.
What are the important input molecules in ATP energy generation?
Pyruvic Acid (or Pyruvate)
Acetyl Coenzyme A
O2 (Oxygen)
ADP
What are the important coenzymes/cofactors in ATP energy generation?
Ubiquinone Coenzyme A NAD+/NADH FAD+/FADH Coenzyme Lipoamide FMN (flavin mononucleide)
What are the important vitamins in ATP energy generation?
Riboflavin (B2)
Thiamine (B1)
Pantothenic Acid (B5)
Niacin (B3)
What are the important Output Molecules in ATP energy generation?
ATP
H+
CO2
What are the important mineral ions in ATP energy generation?
Mg +2 (magnesium) Mn +2 (manganese) Fe +2 (iron) K+ (potassium) Cu +2 (copper)
What enzyme complex takes 3-carbon pyruvate from glycolysis and converts they pyruvic acid to acetyl coenzyme A? What process is this the first step to? What is the primary purpose of this step?
Pyruvate dehydrogenase complex- multiple enzymes that perform several functions with several cofactors in the first stage of
Pyruvate decarboxylation. The main output from the pyruvate dehydrogenase complex is acetyl coenzyme A.
Why is the Krebs Cycle often called the Citric Acid Cycle?
because Citric Acid is the first molecular product when Acetyl Coenzyme A is introduced to the cycle, and it is the carbons from Citric Acid that are “burned”
What is the purpose of the Krebs cycle?
to oxidize, burn carbon from ACA (acetyl coenzyme A) and produce energy carrying molecules.
How many energy carrying molecules are produced in the Krebs cycle?
6 energy carrying molecules are produced (3 NADH, 1 FADH2, 1 GTP, 1 succinate)
In sum, Krebs produces: (knowledge for testing purposes)
3 NADH
1 FADH2
2 CO2
Which does NOT happen during pyruvate decarboxylation?
(a) coenzyme A is acetylated
(b) coenzyme lipoamide is recycled
(c) 1 ATP is released
(d) 1 NADH is released
(c) 1 ATP is released
True or False: In a generalized way, the Krebs cycle oxidizes carbon.
True
True or False: The purpose of the Electron Transport Chain is to produce molecules to enter the Krebs cycle.
False
Which molecule is the most abundant product of the Krebs cycle?
NADH
True or False: the fluid-filled areas of the mitochondrion are the inter-membrane space and the matrix.
True
True or False: Acetyl Coenzyme A (ACA) is the only molecule that replenishes carbon in the Krebs Cycle.
True
True or False: Glycolysis can happen in the cytoplasm and in mitochondrion.
True
