Questions tagged [cellular-respiration]
The process in which energy is liberated from organic molecules producing ATP.
164
questions
1
vote
1
answer
194
views
Do plants refix some of the carbon dioxide in the Calvin cycle that they produce through cellular respiration?
Plants do cellular respiration and release CO2 into the air, but does the plant also use some of this CO2 to do the Calvin cycle? Or does all the CO2 required for the Calvin cycle come in through the ...
3
votes
1
answer
5k
views
Why are there no multicellular prokaryotes [closed]
Why don't complex multicellular prokaryotes exist and also what makes eukaryotes multicellular?
2
votes
4
answers
163
views
Is there any organism that is born with all the nutrients and resources needed for their entire lifetime?
I understand that adult mayflies have no mouth, but they do take in oxygen through openings in their exoskeleton.
Is there any organism that does not need to ingest any type of nutrition and does not ...
1
vote
1
answer
394
views
What are the differences between mammal and insect digestion of cellulose?
I know that digestion of cellulose is difficult in mammals and requires a lot of steps. But I am fascinated by the idea of one day achieving human digestion of cellulose.
Which got me thinking about ...
4
votes
2
answers
2k
views
Where is the H+ ion in this step of glycolysis coming from?
(from Fundamentals of Biochemistry by Voet, 5th ed.)
In this step of glycolysis, I'm not seeing where the $\ce{H+}$ ion on the product side is coming from. It seems to me that the G3P's aldehydic H ...
0
votes
0
answers
98
views
Fructose vs glucose
I was watching a video on the dangers of fructose and comparing it to alcohol and all of this stemming from the fact that the liver can not break down fructose like it can glucose. But then I was ...
4
votes
1
answer
4k
views
Mitochondria - are they really separate organisms that once merged into eukaryotic cells? [closed]
Theoretically, mitochondria are said to be a separate organism that is concerned with its own life and its own processes. In fact, it even duplicates individually. I know a similar question is here ...
1
vote
1
answer
35
views
Can Phosphogycolate buildup in a plant kill it?
I'm trying to think of some things for the science fair, for part of my experiment I need to know if Phosphogycolate build up in a plant can kill it. Also, are there any chemicals that may disrupt the ...
1
vote
1
answer
441
views
What triggers the switch between aerobic and anaerobic respiration?
I understand that when there is a shortage of oxygen cells convert the pyruvic acid from glycolysis to lactic acid to regenerate NAD+. What I don’t understand is how they switch to anaerobic ...
5
votes
4
answers
11k
views
Why are H+ ions pumped out instead of in during cellular respiration
During cellular respiration in both mitochondria and aerobic prokaryotes, the Electron Transport Chain pumps H+ ions out of the matrix or cytoplasm to create a H+ concentration gradient. This forces ...
4
votes
0
answers
334
views
Where do the protons in the mitochondrial intermembrane space originally come from?
I'm currently reviewing this concept in cellular respiration. The book which I'm using is Reece, Minorsky, Campbell's Biology and while it does a good job at explaining the process involved in the ...
2
votes
0
answers
39
views
Electron Transport Chain Proton Pumping into the Intermembrane Space
In regards to the electron transport chain, I know that complex I pumps 4 H+, complex III pumps 4 H+, and complex IV pumps 2 H+, but where do these numbers come from? If someone could explain this, ...
3
votes
2
answers
9k
views
Why is ATP used as a source of energy rather than glucose?
I'm struggling to pinpoint a misconception, but I don't think I understand why ATP is used as an energy molecule instead of glucose. I understand that glucose is respired, oxidised or combusted and ...
7
votes
2
answers
1k
views
Why is ATP synthase sometimes referred to as ATPase?
Quite a few times I have seen the term ‘ATPase’ used for what I would consider ATP synthase. For example, my text has:
“The phosphorylation of ADP to ATP is also catalysed by the enzyme ATPase.”
I ...
3
votes
2
answers
326
views
How is Coenzyme A Transported to the Matrix?
So, I've been researching cellular respiration on my own, and trying to keep track of most of the major processes. However, I do have one question left: I can't seem to find any sort of information ...
5
votes
2
answers
3k
views
What is the source of the electrons generated in the Krebs cycle?
In the Krebs cycle, where do the hydrogens and electrons that NAD+ and FAD accept come from? It seems that citric acid only loses two hydrogens because it starts out with eight hydrogens and then ...
1
vote
1
answer
4k
views
Cellular Respiration in Boiling Conditions
Here's the question:
Imagine that you are given 25 germinating pea seeds that have been placed in boiling water for 5 minutes. You place these seeds in a respirometer and collect data. Predict the ...
21
votes
2
answers
12k
views
Given ATP synthase's structure, how can 3.33 protons ultimately synthesize one and only one ATP?
I am familiar with the structure and function of ATP synthase, but one small detail doesn't seem to make sense. It also happens to be a detail that seems very hard to express.
Depending on the ...
9
votes
2
answers
1k
views
What preceded ATP synthase?
ATP Synthase is ubiquitous throughout life on earth and so most probably evolved within the last universal common ancestor (LUCA) before that lineage diversified into the various kingdoms of life.
...
1
vote
0
answers
242
views
In electron transport system the final acceptor of proton is?
My lecture notes say that the answer to this is inorganic phosphate (iP)..and the question is about proton not electron so the answer can't be oxygen. But I don't understand how is the answer iP
4
votes
1
answer
4k
views
Why does ATP contain ribose rather than deoxyribose?
I read in a textbook that ATP is made from ribose and not deoxyribose. Originally, I thought that the pentose sugar didn’t have functional importance.
Is there a functional reason why the ATP used ...
3
votes
2
answers
806
views
How can the leakage of mitochondrial protons generate heat?
I read the following about thermogenin:
"When thermogenin is
inserted into the inner mitochondrial membrane, it
accentuates mitochondrial proton leak and dissipates
the proton motive force. ...
2
votes
1
answer
388
views
As electrons are moving through the ETC, how is ATP produced for the active transport to even happen?
A lot of websites aren't being specific and they are just saying that when electrons move from a high to low energy state during the ETC, "energy" is being released and that energy is used to pump (...
33
votes
5
answers
8k
views
Why isn't Fluorine, or Neon, the final electron acceptor in cellular respiration?
I'm a Chemistry student learning about periodic trends. I know that in (many organisms') cellular respiration, oxygen serves as the final electron acceptor due to its high electronegativity.
However, ...
0
votes
1
answer
686
views
Why in the Electron Transport Chain does PS2 go before PS1? [closed]
Why in ETC does PS2 go before PS1?
2
votes
2
answers
1k
views
ATP production via aerobic respiration
Just started learning about aerobic respiration today, specifically Glycolysis.
We were told that aerobic respiration produces 38 ATP, while anaerobic respiration produces only 2.
However, we're ...
1
vote
0
answers
570
views
The effect of sugar on rate of yeast Respiration
In my experiment, I am investigating the effect of different types of sugar on the rate of respiration of immobilized yeast (yeast trapped in calcium alginate balls). I am looking at glucose, fructose,...
-1
votes
1
answer
135
views
What happens to the ATP after it stores energy?
The title says it all. After the procceses of cellular respiration happen, the energy is used in different activities that use it, but which are them, more specifically?
14
votes
2
answers
87k
views
How do prokaryotes perform cellular respiration without membrane-bound organelles?
In order to survive, prokaryotes such as bacteria need to produce energy from food such as glucose. In eukaryotic cells, respiration is performed by mitochondria, but prokaryotic cells do not have ...
2
votes
1
answer
986
views
Negative Oxygen Consumption Rate
Oxygen consumption rate (OCR) is defined as the rate at which cells consume oxygen. I reason that for cells not capable of photosynthesis, OCR is strictly non-negative.
That was until I read this ...
1
vote
0
answers
91
views
fermentation in soil bacteria
I am doing a project on microbial fuel cell. For the purpose of the efficiency of the question, MFCs can be summarized to:
Devices that use anaerobic bacteria as the catalysts to oxidize organic ...
0
votes
0
answers
401
views
Effects of Free Electrons In a Cell?
I am very new to biology, currently just a student. Recently I learned of the electron transport chain used in cellular respiration. This got me thinking. At the end of the chain, the electrons are ...
8
votes
1
answer
7k
views
How much oxygen does a plant use up at night?
Given the fact that plants cannot do photosynthesis at night but need respiration for their energy needs, they use up oxygen and generate carbon dioxide. But how much is this? If I fill a room with ...
1
vote
2
answers
2k
views
Intermediate of Krebs cycle that can form Chlorophyll?
This was a question in a test in my school today.
Q) Which intermediate of Krebs cycle further can form chlorophyll?
A) Oxaloacetic acid
B) Citric acid
C) Succinyl CoA
D) Fumarate
Given answer was ...
0
votes
1
answer
584
views
Why do zoologists classify sponges as animals rather than plants?
Sponges are fixed, do not move settle at one place, do not have a reproductive apparatus, respiratory apparatus, or organs, and live in marine environments. Why then zoologists consider that sponges ...
2
votes
1
answer
760
views
Viability of argon-oxygen atmosphere
Can humans breathe an Argon-Oxygen atmosphere, where Argon substitutes the inert Nitrogen gas which currently populates our atmosphere? I didn't quite know which forum to stick this one in; I put it ...
1
vote
0
answers
555
views
Entropy increase or decrease in an reaction
My question is how would you tell if the product of an reaction has more or less entropy than the reactants?
For example, in glycolysis, when glyceraldehyde-3-phosphate becomes 1-3 ...
4
votes
2
answers
2k
views
Pyruvate as a final electron acceptor in the electron transport chain
During anaerobic respiration, why are electrons carried by NADH not transferred to the electron transport chain (ETC)? What happens is that lactate dehydrogenase reduces pyruvate to lactate, while ...
2
votes
0
answers
759
views
Is oxygen a respiratory substrate
I know that carbohydrates such as glucose are respiratory substrates for cellular respiration, but in this process, oxygen is also used to produce ATP so is it also a respiratory substrate?
2
votes
2
answers
2k
views
Role of ATP and AMP in functioning of Phosphofructokinase
I know that when ATP is more then it inhibits PFK and hence regulate the number of ATP. But how does PFK reactivates itself? Is it due to removal of ATP from allosteric site that just reconfigures the ...
1
vote
0
answers
346
views
How long can algae survive with no air recycling (closed bottle)
In a small bottle nearly filled of Chlorella in water and grow medium, how long would it take for them to die (with or without light).
Thanks in advance ;)
5
votes
1
answer
3k
views
Membrane Permeability to Pyruvate
Pyruvate seems to pass easily through the outer membrane of the mitochondrion but has difficulty entering the inner membrane (and gets in by H+ symport). I have two questions: (1) what property of ...
8
votes
1
answer
12k
views
Why is carbon dioxide produced in alcohol fermentation but not in lactic acid fermentation?
From my understanding, alcohol fermentation takes place in yeast and lactate production takes place in humans.
These two pathways take place only when there is insufficient oxygen, because the other ...
0
votes
1
answer
428
views
Do seeds use cellular respiration when they are germinating?
Do seeds use cellular respiration when they are germinating?
7
votes
2
answers
12k
views
How many molecules NADH are produced in the Krebs Cycle?
I don't know which source i'm going to follow.
Some say its 3 molecules NADH per cycle → 2 cycles × (3 NADH) = 6 NADH
Some say its 4 molecules NADH per cycle instead?
3
votes
2
answers
1k
views
Facultative anaerobic organism
While I was studying Cellular Respiration: Harvesting Chemical Energy, I found this question:
An organism is discovered that consumes a considerable amount of sugar, yet does not gain much weight ...
0
votes
1
answer
75
views
Is it possible to consume O2 via a pill form to inhibit the need to breathe?
Just wondering if it would be theoretically possible to consume oxygen via O2 pills, in the effort of being able to hold one's breath without limit.
Totally just curious.
2
votes
0
answers
404
views
In what reaction of mitochondrial respiration is hydrogen peroxide an anomalous product?
I understand that hydrogen peroxide is produced in an anomalous manner during mitochondrial respiration, which also produces other by-products or free radicals. Does anyone know the details of the ...
7
votes
1
answer
234
views
Cell Respiration and Oxidative Phosphorylation
Why and how does the proton travelling through the stalked particle in the inner mitochondrial membrane, cause a conformational change in the ATPase?
4
votes
1
answer
9k
views
Cellular Respiration/Fermentation Problem Leading to Lack of Energy
A young animal has never had much energy. He is brought to a veterinarian for help and is sent to the animal hospital for some tests. There they discover his mitochondria can use only fatty acids and ...