Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
20 Cards in this Set
- Front
- Back
|
1. Does gluconeogensis occur in muscles?
2. How does sympathetic stimulation affect glycolysis in the liver? |
1. No
2. Stops glycolysis in liver so liver can ship off glucose to muscles |
|
|
1. What is the equation for cellular respiration?
|
1. C6H12O6 + 6O2 -> 6 CO2 + 6 H2O + energy
|
|
|
What are the three stages of cellular respiration?
|
1. Oxidation of fatty acids, amino acids or glucose to acetyl CoA
2. Oxidation of acetyl CoA to yield 4 CO2 molecules. Electrons are stored (6 NADH and 2 FADH2), one ATP per pyruvate produced 3. Transfer of electrons to oxygen. Generates water and proton gradient. |
|
|
1. What is acetyl CoA and how is it formed?
2. What is the structure of Coenzyme A similiar to? What can interfere with it? |
1. Acetyl-CoA is a high energy thioester, which is formed by splitting pyruvate using pyruvate dehydrogenase.
2. Similar to RNA/DNA. A Vitamin B deficiency can impact this. |
|
|
1. What is the pyruvate dehydrogenase complex?
2. Why do we have such big complexes? |
1. Has three enzymes and 5 cofactors (present in many copies)
2. Enhanced reaction rates, decreases unwanted reactions and makes regulation easy. (Major regulatory point at pyruvate dehydrogenase complex) |
|
|
1. What are the basics of how pyruvate dehydrogenase complex operates?
2. What does arsenic do? |
1. Splits CO2 from pyrvuate and takes the rest of the molecule in a big arm swing to attach to S-CoA. Generates NADH.
2. Inactivates E2, thus disabling this entire complex. |
|
|
1. How is pyruvate dehydrogenase regulated?
2. What inhibits pyruvate dehydrogenase activation? 3. What activates it? |
1. If pyruvate dehydrogenase is phosphorylated, then it is active. (covalent modification)
2. NADH, acetyl CoA, long chain fatty acids 3. AMP, CoA and NAD+ |
|
|
1. For each pyruvate in TCA, what are the products?
2. What does citrate synthase do? |
1. 3 NADH, 1 FADH2 and 1 GTP. Also CO2, but it is not from acetyl-CoA in the first round, released in subsequent rounds
2. Part of the first step in TCA, makes citrate. Releases CoA so it can be used again. Oxaloacetate binds first to induce conformational change which prevents unwanted reactions. Releases lots of free energy (condensation). |
|
|
1. What does aconitase do?
2. What is prochiral? |
1. Isomerization (citrate -> cis-aconitate), but is reversible reaction with cirtrate favored. Can recognized prochiral.
2. Two groups are the same off the carbon backbone chain. Can't tell which end of the molecule is up or down. (but the body can!) |
|
|
1. What else is aconitase used for?
|
1. Gene regulation of iron homeostasis. Aconitase has an iron center. The body's concentration of iron changes the function.
2. High iron corresponds to the TCA. Low iron makes a conformational change and it can bind to RNA with iron response element. |
|
|
1. Is there one point where TCA is regulated?
2. How is the TCA regulated? |
1. No
2. Substrate availability, product inhibition (direct, like citrate inhibits citrate synthase) and competitive feedback inhibition, like ATP. NADH really important regulator on cycle. |
|
|
1. What are cataplerotic reactions?
2. What are anaplerotic reactions? |
1. Reactions that use TCA intermediates like glucose, fatty acid or amino acid biosynthesis.
2. Reactions that replenish TCA intermediates. |
|
|
1. Upon reaching the ETC, how many energy sources have we made?
2. What are the main roles of the mitochondria? |
1. 4 ATP, 10 NADH, 2 FADH2
2. Produce ATP by oxidative phosphoyrlation and regenerate electron carriers. |
|
|
1. What is the mitochondria outer membrane used for?
2. The inner membrane? 3. Matrix? |
1. Has porins, which means relatively permeable. Also has enzymes for mitochondrial lipid synthesis.
2. Folded into cristae for surface area, impermeable to most small ions, has transporters, ETC and ATP synthase in it. 3. Enzymes for TCA, mitochondrial DNA |
|
|
1. What makes up the ETC?
2. What pumps more protons, NADH or FADH2? |
1. 4 protein complexes that shuttle electrons. Have lots of prosthetic groups, and two electron shuttles. Coenzyme Q is hydrophobic in the inner membrane, Cytochrome C is peripheral protein.
2. NADH starts one complex sooner than FADH2, so pumps more protons. |
|
|
1. What does a high reduction potential mean?
2. What should have the highest reduction potential in the ETC? |
1. Molecule really wants an electron.
2. Oxygen |
|
|
1. What is the proton motive force responsible for generating?
2. What does ATP synthase do? |
1. pH gradient, with lots of protons in the intermembrane space (low pH). Also a voltage gradient with a negatively charged matrix.
2. Lets a proton go from intermembrane space to matrix |
|
|
1. What are the three conformations of the beta subunit of ATP synthase?
2. How do these conformations change? |
1. O (open, ATP leaves, low affinity), L (loose high affinity for ADP and Pi), T (tight, high affinity to squish ADP and Pi -> ATP)
2. As the gamma subunit rotates, it changes the conformations of Beta subunits. A full rotation gives 3 ATPs |
|
|
1. How does ATP get out of the mitochondria?
2. How much ATP is generated by cellular respiration? |
1. The electric gradient forces the negatively charged ATP out of the matrix and into the positively charged intermembrane space where it diffuses out.
2. 30 or 32 |
|
|
1. How many ATP do you get per NADH?
2. Per FADH2? |
1. 2.5
2. 1.5 |
