What I’ve Been Eating Lately + Respiration for non-Bio-and-or-Chemistry Majors (plus genetic, microbiology, kinesiology, etc.)

Happy February, folks!

I wanted to quickly update you on some aspects of my life that I haven’t vocalized very often on my Instagram (not to be repetitive or anything of that sort):

  • Being a teaching assistant is amazing, but the labs on Mondays back-to-back can be a little taxing–maybe I just hate the act of discarding half-eaten food samples, but nothing is perfect.
  • Due to my limited schedule, I haven’t worked at Mama Ganache nearly at all this quarter. I still love it!
  • I have officially finished by first senior project preliminary report on our blueberry ketchup product development!
  • My second senior report is almost done–we still have a few weeks of experimentation to complete.
  • Midterm season began since Week 3. I’m expecting one on Tuesday and then one on Thursday.
  • I got to meet Dr. Michael Greger!
  • And I met Miyoko Schinner!
  • Workout routine is pretty much the same.
  • My step count ranges from 13,000-15,000.
  • Using a portable charger for my iPhone has been SUCH a life-saver.
  • It’s much harder to find a good time slot to cook for the Food Science club meetings. We usually end up whipping up relatively simple meals we can bake or roast in large hotel pans or boil in a large pot. Rice, chopped fruit, and some kind of protein for days. I wish it was more creative, but oh well.
  • I GOT MY DREAM INTERNSHIP FOR A PLANT-BASED BIOTECH COMPANY!!!!

Below is what I’ve been eating lately! You can check it all out on my Instagram, but at the very least–my fruit and vegetable intake have increased a little bit! I’ve fallen in love with large salads, large bowls of kamut puffs, dairy free ice cream sticks, peanut butter powder, nut and seed granola, and kettle corn. Oh yes, and TVP, air-fried kabocha squash, and The Vreamery vegan cheese.

Posting this for personally selfish reasons because I need to study (LOL): below is the entire breakdown of how aerobic and anaerobic respiration works for anyone who needs this for passing a certain GE, learning more about metabolism, or if you are so knowledgeable in this subject that you may actually want to laugh at me for not choosing biochemistry or any related field of study. I get that.

GLYCOLYSIS (total of nine steps–this is just a general overview)

  1. Glucose, a six-carbon molecule, receives two phosphate molecules by two ATP. This happens in two separate steps.
    1. ATP (adenosine triphosphate) becomes ADP (adenosine diphosphate).
  2. The phosphorylated glucose is split into two pyruvate molecules (three-carbon molecules, each with one phosphate). This happens twice.
  3. Coenzyme NAD+ receives a hydrogen from one of the pyruvate molecules (reduction reaction), resulting in NADH, which move towards the electron transport chain. This happens twice.
  4. An inorganic phosphate is added to the third carbon of a pyruvate molecule, making it unstable and reactive. This happens twice.
  5. Substrate level phosphorylation (again, happens twice): One of the unstable phosphates is donated to the ADP molecule.
  6. Four total ATP molecules (NET two ATP) and two pyruvate molecules are produced.

KREBS CYCLE (mitochondrial matrix)

  1. Glycolysis and the Krebs cycle are linked by the reduction of NAD+ and removal of a carbon dioxide molecule, breaking down glucose, converting pyruvic acid to acetyl coenzyme A.
  2. Four carbon oxaloacetate reacts with a two-carbon acetyl group on acetyl CoA to form six-carbon citrate and release coenzyme CoA.
  3. Citrate forms into six carbon isocitrate.
  4. Isocitrate is converted into five-carbon alpha-ketoglutarate, yielding NADH and carbon dioxide (as a waste product) by an enzyme complex including NAD+ or NADP (this is a decarboxylation and redox reaction).
  5. Alpha-ketoglutarate reacts with coenzyme CoA as a substrate, loses its second carbon dioxide molecule, and forms NADH+ and a four carbon succinyl CoA (decarboxylation and redox reaction).
    1. Two carbons are lost in pyruvate processing, leaving four left in the two acetyl CoA’s before the Krebs cycle.
    2. Two acetyl CoA’s come in per reaction.
    3. Four carbons are lost in the Krebs cycle, leaving a total of six carbons lost.
  6. Succinyl CoA is converted to succinate and recreates CoA, producing an ATP molecule (in prokaryotes) or GTP molecule (in eukaryotes) and four carbon succinate via substrate-level phosphorylation.
  7. Succinate loses two hydrogen molecules and two electrons to acceptor FAD, catalyzed by succinyl dehydrogenase. This yields a four carbon fumarate and FADH2, which goes into the electron transport system.
  8. Fumarate receives water, which results in four carbon molecule malate.
  9. Malate is dehydrogenated to oxaloacetate to reenter the cycle and react with acetyl CoA, forming a second and the final NADH molecule. Carbon dioxide is yielded as a waste product.

MAIN TAKEAWAYS:

  • Two carbons come in creating six carbon compounds citrate, then isocitrate through rearrangement (reduce NAD+ to NADH as electron carriers, yielding CO2 as a waste product)
  • One carbon is lost from the six carbon molecule, resulting in five carbon molecule alpha-ketoglutarate
  • One carbon is lost from the five carbon molecule, creating succinyl CoA
  • Succinyl CoA is arranged into succinate, yielding ATP
  • FAD+ is reduced to FADH2 when succinate is arranged into fumarate
  • Converting fumarate to malate requires water
  • Malate transforms into oxaloacetate, reducing a second NAD+ to NADH
  • Oxaloacetate returns back to acetyl CoA, yielding carbon dioxide as a waste product, 2 NADH,

ELECTRON TRANSPORT CHAIN (occurs in mitochondrial matrix through several complex sites)

  1. Complex I: reductaste multi-enzyme cluster NADH dehydrogenase receives NADH from glycolysis and Krebs cycle, oxidizing NADH to NAD+
    1. Pumps protons
  2. Complex II: made of a series of iron-sulfur (FeS) proteins that receive electrons from FADH2 produced in the sixth step of the Krebs cycle; it converts succinate to fumarate from the oxidation of FAD to transport electrons to Complex III
  3. Complex III: oxidizes ubiquinol (form of coenzyme Q10), reduces two cytochrome-c molecules, releases protons, and transports the electron to complex IV
    1. Cytochrome c: mobile carrier delivered by cytochrome b and c1, shuttles electrons between complex III and complex IV
    2. Pumps protons
  4. Complex IV: catalyzes reaction between electrons, H+, and oxygen to yield water and complete electron transfer process
    1. This complex uses ATP synthase to transport protons back into the matrix and generate energy used to achieve phosphorylation of ADP molecules to form ATP.
    2. Pumps protons

THEORETICAL ATP YIELD FOR AEROBIC RESPIRATION

GLYCOLYSIS: 2 NADH’s, 2 net ATP (substrate level phosphorylation) (6 ATP’s from oxidative phosphorylation)

PYRUVATE PROCESSING: 6 ATP molecules

KREBS CYCLE: 6 NADH’s to 18 ATP, 2 FADH2’s to 4 ATP, 2 ATP molecules (substrate level phosphorylation)

TOTAL AEROBIC YIELD: 38 ATP maximum


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