What is phosphocreatine (PCr) primarily used for?
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ATP resynthesis.
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What is phosphocreatine (PCr) primarily used for?
ATP resynthesis.
What is the primary energy currency in cells?
ATP (Adenosine Triphosphate).
What are cytochromes?
A series of iron-protein electron carriers in the inner membranes of the mitochondrion.
What is the primary focus of Chapter 6 in Exercise Physiology II?
Energy Transfer in the Body.
What is the primary source of energy for phosphorylation?
The oxidation of dietary carbohydrate, lipid, and protein macronutrients.
What process do carrier molecules in mitochondria perform?
They remove electrons from hydrogen (oxidation) and pass them to oxygen atoms (reduction).
How much more phosphocreatine do cells store compared to ATP?
Approximately 4 to 6 times more.
Which enzyme catalyzes the reaction of ATP with water?
Adenosine triphosphatase (ATPase).
What is the primary energy currency in cells?
ATP (Adenosine triphosphate).
What is the function of Flavin adenine dinucleotide (FAD) in cellular oxidation?
It serves as an electron acceptor and becomes FADH2 by accepting two hydrogens.
Do food macronutrients transfer energy directly to biological work?
No, they do not transfer directly.
What provides an energy reserve in the body?
Phosphocreatine.
What is the relative efficiency of harnessing chemical energy via electron transport and oxidative phosphorylation?
34%.
How many ATP molecules are produced on average from the oxidation of one NADH?
2.5 molecules of ATP.
What is phosphocreatine (PCr) primarily known for?
Being an energy reservoir.
How quickly does phosphocreatine reach its maximum energy yield?
In about 10 seconds.
What is the ATP yield from the catabolism of carbohydrates compared to fats and proteins?
Carbohydrates yield different amounts of ATP compared to fats and proteins, with fats generally yielding more ATP.
What is the role of the citric acid cycle in energy metabolism?
The citric acid cycle generates energy through the oxidation of acetyl-CoA, producing ATP, NADH, and FADH2.
What role does the citric acid cycle play in ATP production?
It generates electron carriers that feed into the electron transport chain.
What is phosphocreatine (PCr) primarily used for in cells?
As an energy reservoir.
What macronutrients provide the majority of our required energy?
Carbohydrates, lipids, and proteins.
What are mitochondria often referred to as?
The cell’s 'energy factories.'
How many distinct coupling sites are involved in the energy transfer from NADH to ADP during electron transport?
Three distinct coupling sites.
How many ATP molecules are formed for each hydrogen pair oxidized from FADH2?
2 ATP molecules.
What are two contributions of high-energy phosphates for energizing biological work?
High-energy phosphates provide immediate energy for cellular processes and help in the resynthesis of ATP.
What happens to lactate formation during increasing exercise intensity?
Lactate formation increases as exercise intensity rises due to anaerobic metabolism.
What is produced alongside NADH during the reduction of NAD+?
H+ appears in the cell fluid.
How does energy from macronutrient breakdown funnel through?
Through ATP.
What is the primary energy currency of the cell?
ATP (Adenosine Triphosphate).
Why must ATP be resynthesized?
Because cells contain a small quantity of ATP.
How much ATP does the body store under normal resting conditions?
80 to 100 grams.
What is considered the energy currency of the cell?
ATP.
What are the interconversions among carbohydrates, fats, and proteins?
Carbohydrates, fats, and proteins can be converted into one another through various metabolic pathways, allowing the body to utilize different macronutrients for energy.
Which process generates ATP in the absence of oxygen?
Anaerobic glycolysis.
What is released during the hydrolysis of ATP?
7.3 kcal of free energy.
What are the two main electron donors in oxidative phosphorylation?
NADH and FADH2.
What does ATP provide for the cell?
Potential energy that powers all energy-requiring processes.
How long can the stored ATP power maximal exercise?
2 to 3 seconds.
How many ATP molecules are produced on average from the oxidation of one FADH2?
1.5 molecules of ATP.
What forms when ATP joins with water?
Adenosine diphosphate (ADP).
What is the energy change (∆G) when ATP is converted to ADP?
-7.3 kcal/mol.
What is necessary for energy transfer reactions to proceed at the appropriate rate?
Sufficient concentration of enzymes and mitochondria.
What is the primary energy currency in biological systems?
ATP (Adenosine Triphosphate).
Does the body store large quantities of ATP?
No, the body doesn’t store large quantities of ATP.
What is the role of oxygen in oxidative phosphorylation?
It acts as the final electron acceptor.
What is the title of the article by Mcewen et al. published in 2011?
Neurotherapeutics.
What types of reactions are coupled in energy metabolism?
Oxidation reactions (donating electrons) and reduction reactions (accepting electrons).
What molecules carry electrons to the cytochromes?
NADH and FADH2.
What is required to shuttle hydrogens to the electron transport chain?
Some energy.
How do cells conserve energy from food?
By extracting potential energy and storing it within ATP bonds.
What role do dehydrogenase enzymes play in cellular oxidation?
They catalyze the release of hydrogen from nutrient substrates.
What is the significance of phosphocreatine in ATP resynthesis?
It provides a rapid source of energy by donating a phosphate group to ADP.
What do NADH and FADH2 do in cellular metabolism?
They shuttle electrons to the electron transport chain for oxidative phosphorylation.
How does energy from macronutrient catabolism relate to ATP?
Energy from macronutrient catabolism funnels through ATP.
In which volume and issue was the article by Mcewen et al. published?
Volume 8, Issue 2.
What is ATP considered in cellular metabolism?
A limited currency.
How do cytochromes function in electron transport?
They pass pairs of electrons in a 'bucket brigade' fashion.
What is a thinking point regarding ATP usage?
How much ATP does it take to run a marathon?
During what type of reactions does ATP synthesis occur?
During redox reactions.
What is the typical amount of ATP stored in the body under normal resting conditions?
80 to 100 grams.
How many ATP molecules are produced on average from the oxidation of one NADH?
2.5 molecules of ATP.
What do oxidation and reduction reactions provide for energy metabolism?
They provide hydrogen atoms from the catabolism of stored macronutrients.
How long can the stored ATP power maximal exercise?
2 to 3 seconds.
What does the phrase 'fats burn in a carbohydrate flame' mean?
It means that carbohydrates are necessary for the complete oxidation of fats, as they provide the intermediates needed for fat metabolism.
What happens to NAD+ during cellular oxidation?
It gains hydrogen and two electrons, reducing to NADH.
What is the main function of the electron transport chain in ATP production?
To create a proton gradient that drives ATP synthesis.
How much more phosphocreatine do cells store compared to ATP?
Approximately 4 to 6 times more.
What does the electron transport chain represent?
The final common pathway where electrons extracted from hydrogen pass to oxygen.
How much energy does each mole of ATP formed from ADP + P conserve?
About 7 kcal.
What are the page numbers for the article by Mcewen et al.?
Pages 168-179.
How many ATP molecules are produced on average from the oxidation of one FADH2?
1.5 molecules of ATP.
How does phosphocreatine contribute to ATP re-synthesis?
By anaerobically splitting a phosphate from PCr.
What role does NADH or FADH2 play in ATP re-synthesis?
They serve as reducing agents.
What is required to shuttle hydrogens to the electron transport chain?
Some energy.
What process contributes to ATP resynthesis from phosphocreatine?
Anaerobic splitting of a phosphate from PCr.
What role does ATP play in biological work?
It provides the chemical energy needed to power biological work.
What is the primary method of ATP production in aerobic conditions?
Oxidative phosphorylation.
What is the efficiency of energy transfer in cellular metabolism?
It varies, but typically around 40% of energy from nutrients is converted to ATP.
How quickly does phosphocreatine reach its maximum energy yield?
In about 10 seconds.
What happens for each pair of hydrogen atoms in the electron transport chain?
Two electrons flow down the chain and reduce one atom of oxygen to form one water molecule.
Why does FADH2 result in fewer ATP molecules compared to NADH?
Because FADH2 enters the respiratory chain at a lower energy level beyond the first ATP synthesis site.
What are two important functions of carbohydrates in energy metabolism?
Carbohydrates serve as a primary energy source and are involved in the regulation of blood glucose levels.
Why is oxygen important in oxidative phosphorylation?
It acts as the oxidizing agent in tissues.
How does substrate-level phosphorylation produce ATP?
By transferring a phosphate group from a substrate to ADP.
What process synthesizes ATP by transferring electrons from NADH and FADH2 to oxygen?
Oxidative phosphorylation.
What is the adenylate kinase reaction used for?
ATP regeneration.
What are the two major energy transforming activities of cells?
What are the three prerequisites for continual re-synthesis of ATP during coupled oxidative phosphorylation?
What does the coenzyme component of dehydrogenase do?
It accepts pairs of electrons (energy) from hydrogen.
What do food macronutrients provide?
Major sources of potential energy.
What is the equation for the adenylate kinase reaction?
2 ADP → ATP + AMP.
What percentage of ATP synthesis occurs in the respiratory chain through oxidative phosphorylation?
More than 90%.
What role does mitochondrial oxygen play in the respiratory chain?
It serves as the final electron acceptor to combine with hydrogen to form water.
What is released during the passage of electrons down the electron transport chain?
Enough energy to re-phosphorylate ADP to ATP.
