16/08/2026
TCA CYCLE WAS'NT JUST A CYCLEβ¦ UNTIL BIOCHEMISTRY STARTED. πππ§¬
When I first heard about the TCA cycle, I thought:
βA cycle? Fine. How difficult can that be?β π
Then Biochemistry introduced me to:
Citrate.
Isocitrate.
Ξ±-Ketoglutarate.
Succinyl-CoA.
Succinate.
Fumarate.
Malate.
Oxaloacetate.
I looked at the pathway.
The pathway looked back at me.
And I immediately understood why they called it a cycle...
Because my brain was going in circles. ππ
Then came the enzymes.
Citrate synthase.
Aconitase.
Isocitrate dehydrogenase.
Ξ±-Ketoglutarate dehydrogenase.
Succinyl-CoA synthetase.
Succinate dehydrogenase.
Fumarase.
Malate dehydrogenase.
At this point, I stopped asking:
βWhat happens next?β
I started asking:
βWhy am I here?β ππ
Then the lecturer asked:
βWhat is the rate-limiting enzyme of the TCA cycle?β
I knew it.
I had read it.
I had highlighted it.
I had even explained it to my friend yesterday.
But in that moment...
My brain decided to run its own metabolic pathway. π
Then came the products:
3 NADH.
1 FADHβ.
1 GTP.
And COβ...
I started counting them like money. π
Then they told us the TCA cycle is amphibolic.
I said:
βPlease, Biochemistry. We are already struggling. Why are you adding grammar?β ππ
But eventually, I realized the TCA cycle wasn't just another pathway to memorize.
It is a central metabolic hub connecting the metabolism of carbohydrates, fats, and proteins.
Pyruvate enters through acetyl-CoA.
Fatty acids contribute through acetyl-CoA.
Amino acids can enter at different points.
And the cycle generates reducing equivalents that drive ATP production through the electron transport chain.
Suddenly...
The "crazy circle" started making sense.
So if you're currently struggling with the TCA cycle...
Don't panic.
You are not alone.
At first, it looks like a collection of impossible names.
Then you understand the sequence.
Then the enzymes.
Then the products.
Then the regulation.
And eventually...
You start teaching someone else. π
Because in medical school...
The topic you once feared can eventually become the topic you explain confidently. π§¬π©Ίβ€οΈ
ββββββββββββββββββββββ
π©Ί ACHILLES MEDICAL
βοΈ Written by: Nweke Hope Chekwube (DE-ACHILLES)
Original content. If you repost, kindly credit the author.