P2: Explain the stages involved in the human respiratory pathway1
Introduction of respiration
This is the process that organisms use to change glucose and oxygen into
carbon dioxide, water, and energy in the form of ATP.
This is the equation for respiration: C6H12O8 (glucose) + 6O2 (oxygen) ==>
6CO2 (carbon dioxide) + 6H20 (water) + energy (ATP)
Glycolysis: The Starting Point
This is respirations first stage; it takes place in the cytoplasm of cells. A small
amount of ATP and NADH are made after the molecules of glucose are made
smaller turning into two molecules of pyruvate. This stage is very important
as it gives out the starting products for subsequent stages and it also begins
the breaking down of glucose. This takes place inside of the cytoplasm which
makes all other types of cells have easy access to it.
- This makes a tiny amount of ATP, net gain of two molecules of ATP per
molecule of glucose
- It yields two NADH molecules that carry electrons which have high-
energy for further extraction of energy
1
1
, Link Reaction: Bridging the Gap
This stage follows up after the glycolysis stage, those same pyruvate
molecules go into the mitochondria – this is where the link reaction occurs.
Over here the pyruvate is changed into acetyl CoA, it releases CO2 and
starts of NADH, this goes into the next stage of ‘The Krebs Cycle.’ This link
reaction initiates NADH, which is a carrier molecule that is important for the
production of energy and makes the substrate that is needed for the Krebs
cycle. This step also links glycolysis to it through the cycle of citric acid
making the substrate for the whole cycle. It connects cytoplasmic glycolysis
to processes to do with the mitochondria since it takes place inside the
mitochondria.
- Starts off NADH by using acetyl-CoA to oxidize pyruvate
- As a byproduct, carbon dioxide is released
2
2
, Krebs Cycle: Powerhouse of Energy Production
This cycle, also known as the citric acid cycle, occurs in mitochondria's
matrix. Acetyl CoA is oxidized whilst this cycle takes place, this causes CO2 to
be released which then initiates ATP, NADH, and FADH2 molecules. This step
is very essential since it makes carriers of high-energy like NADH and FADH 2,
ATP, which are used in the last stage of respiration. This step gives out
‘inbetweeners’ for the biosynthesis and keeps cellular metabolism in check.
- Generates two molecules of ATP per molecule of glucose via substrate-
level phosphorylation
- Makes electrons carriers with high energy for the ETC
3
Glycolysis Explained in 10 Easy Steps (With Diagrams)
By Sagar Aryal Year: 2019 Container: Microbiology Info.com URL:
https://microbiologyinfo.com/glycolysis-10-steps-explained-steps-by-steps-with-diagram/
3
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller bushrahabib. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for £15.49. You're not tied to anything after your purchase.