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The exchange of gases across organs that facilitate transport of the gases to and from the cells of the organism.

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13 views

Why would BMR depend on the weight ?Also, how does the BMR correlate with the weight of the man?

The question described here is based on interpreting data from the graphs and relates the knowledge of BMR with weight of the man.
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1answer
15 views

Light Hyperoxia

Imagine you're in some lowland way below sea level were the oxygen partial pressure is higher than at sea level but still lower than the 0.5atm limit. Would their be any effect that isn't deadly or ...
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2answers
68 views

Is too much CO2 in the air toxic?

I know that if there is too much CO2 in the air we will have too much greenhouse effect. I would like to know if there is too much CO2 in the room, something like 3% while there is also more that ...
6
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1answer
57 views

Does an old growth forest ecosystem produce more oxygen than it consumes?

I would like to consider an old growth forest ecosystem such as a large part of the Amazonian forest. It is common to refer to such beautiful forests as a source of oxygen for the world. For example, ...
1
vote
1answer
78 views

What is the benefit of oxygen tanks to persons trappped in an enclosed space?

When people are enclosed in an air-tight space, the levels of carbon dioxide will rise to lethal levels (hypercapnia) long before the oxygen is exhausted (hypoxia). For example, the astronauts of ...
0
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0answers
20 views

Anaerobic Respiration vs Aerobic Respiration during physical activity

So I was wondering about the difference between aerobic and anaerobic respiration on the context of burning calories. While swimming we can choose to keep our head up and breathe, or keep our head ...
1
vote
1answer
123 views

Is the rate of photosynthesis higher than the rate of respiration?

In photosynthesis carbon dioxide is used up and oxygen is produced and at the same time plants respire too. So oxygen is used up and carbon dioxide is produced. Then the net exchange of gases should ...
3
votes
1answer
55 views

How is it possible to breathe perflurocarbon?

I have heard of liquid breathing, where an organism, usually a person, would be breathing in perflurocarbon. Now I looked up perflourocarbon on wikipedia and I noticed, no oxygen at all, but fluorine ...
2
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0answers
35 views

How do ants get oxygen in deep colonies?

With ant colonies getting to be +7 feet deep, how does oxygen renew that deep for their respiration demand?
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1answer
45 views

What's the minimum, if any, concentration of atmospheric nitrogen needed by plants?

What's the minimum, if any, concentration of atmospheric nitrogen needed by plants? Would plants be able to grow in an atmosphere with just carbon dioxide and oxygen?
0
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1answer
28 views

Oxygen balence from growing plants for food

I had thought photosynthesis and respiration where pretty much Oxygen and Carbon neutral per calorie. http://news.mit.edu/2014/technical-feasibility-mars-one-1014 If, as the project plans, crops ...
1
vote
0answers
31 views

How much pressure can human withstand if inner and outer pressure is balanced?

I know human can't dive too deep because there's pressure difference between inside and outside of the body. But how much pressure can human withstand if human is breathing components that is ...
1
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0answers
34 views

ATP generation during respiration [closed]

How many ATP molecules are generated from oxidation of FADH2 formed during complete oxidation of 10 molecules of maltose? 40 60 80 20 My method- As maltose is a disaccharide ( made up of two ...
0
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0answers
19 views

Can I supplement breathing by eating a lot of sugar and converting it to lipids?

So obviously not but would it be easier to hold your breath after eating a lot of sugar? My reason is that carbohydrates have oxygen and the fats they get stored into don't, so that oxygen has to go ...
0
votes
1answer
118 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 ...
0
votes
1answer
292 views

If during exercise the affinity of oxygen for haemoglobin is decreased, what are the general consequences for tissues?

During exercise more respiration occurs, and hence more oxygen is required. So the oxygen dissocation curve is shifted to the right. So at a given Oxygen partial pressure, the haemoglobin is less ...
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0answers
23 views

Muscles involved in breathing

What is the role of abdominal muscles in breathing? Please give a explanation in the context of biomechanics.
2
votes
1answer
56 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 ...
4
votes
2answers
214 views

Why does breathing increase in higher temperatures?

In my experiment, my group increased the temperature of a fish's water. We noticed the fish took more breaths than the prior normal temperature. Is this because the fish is trying to breathe in the ...
1
vote
1answer
161 views

Could humans breathe if the average methane content of the atmosphere increased to 1%?

Below is a table of atmospheric composition. Could humans breathe if the average methane content of the atmosphere increased to 1%? Table 7a-1: Current Average composition of the atmosphere up to ...
0
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2answers
54 views

Does exhalation help us speak, and if so, how?

Everyone knows that we breathe in oxygen and breathe out carbon dioxide. That's how the respiratory system works. But we also use the respiratory system to produce sound and language. When we speak or ...
5
votes
1answer
494 views

Where do all the NAD+s come from?

In the mitochondrial respiration (of plant cells) NADH is reduced from Nad+ as part of the TCA (converting malate to oxaleoacetate). But where do the NAD+s come from? The TCA cycle is working even ...
1
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0answers
21 views

Aerobic respiration [closed]

I read a sentence in my biology book while i was reading respiration chapter. i wasnot able to understand it. It was in the process of oxidative phosphorylation" "as the proton pass through channel ...
15
votes
3answers
745 views

Why does a worm's skin need to be wet for oxygen to diffuse across it?

Pages I've read about worms' respiratory systems says that the skin needs to be wet (covered in mucus) or oxygen won't diffuse across the skin. Why? If there is more oxygen outside the worm's skin ...
2
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0answers
261 views

Why do earthworms surface after a rain?

Googling, I find two different explanations for why earthworms tend to surface after a rain. This page from UCSB, for example, gives both answers, contradicting itself: The first explanation is ...
0
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0answers
52 views

What is the lowest atmospheric pressure that humans can survive in naked given any atmospheric composition of gases?

There are plenty of similar posts; having read them, they do not answer my question. Most attempts at answers rely upon low atmospheric pressure conditions on Earth, which have 20.9% oxygen. Answers ...
3
votes
2answers
382 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
1answer
48 views

Oxygen mask to patients

Why are oxygen masks given to patients? Can't they take in the atmospheric oxygen? Also, why do they die if the oxygen mask stops providing oxygen?
5
votes
2answers
1k views

Cooperativity of haemoglobin and oxygen dissociation curve of haemoglobin

Haemoglobin shows positive cooperativity with oxygen. When an oxygen atom binds to one of hemoglobin's four binding sites, the affinity to oxygen of the three remaining available binding sites ...
1
vote
1answer
376 views

Effect of forced breathing on RBC size

Microcytosis, i.e. decrease in the size of RBCs occurs: – In iron deficiency anaemia, – During prolonged forced breathing and – When osmotic pressure of the blood is increased. I am ...
4
votes
3answers
254 views

Why do bacteria eat enamel?

What causes tooth decay bacteria or acids? I've been told that it is a combination of both but why would bacteria eat enamel? There are much easier supplies of protein for bacteria to munch through (...
0
votes
1answer
52 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.
5
votes
1answer
787 views

How could cyanobacteria survive the anaerobic conditions of ancient earth?

I was reading about cyanobacteria and came to know that they are the first organisms that filled the atmosphere with oxygen around 2.3 billion years ago but then I realized that they themselves are ...
1
vote
0answers
29 views

Does vegetable oil allow methane to pass through? [closed]

I'm doing an experiment investigating how temperature affects the rate of methanogenesis. I'm using a peat sample that will be kept in a conical flask connected to a gas syringe with a layer of Janus ...
7
votes
2answers
3k 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 ...
0
votes
1answer
347 views

Can a pyruvate reaction to acetyl coA be called as acetylation in any way? [closed]

Can the oxidation of pyruvate to acetyl coa be called as acetylation in some ways? Please include credible sources in the answer.
1
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0answers
120 views

Oxygen dissociation curve and temperature

So, we have a container with a mixture of gases. The concentration of oxygen is $C_{oxy}$ and its partial pressure is $P_{oxy}$. Then we introduce a sample of hemoglobin(deoxygenated) in that ...
1
vote
2answers
53 views

Does Usnea (Old Mans Beard) have negative effects on the respiratory system?

Being a fungus does it have negative effects similar to that of mold, especially on the respiratory system?
4
votes
1answer
219 views

Does the Valsalva maneuver require a completely closed airway? How do the effects compare to exhalation against partial resistance?

The Valsalva maneuver is defined as "attempted exhalation against a closed airway", "The effort to breathe out forcibly while the mouth and nose are firmly closed or the vocal cords pressed together", ...
0
votes
1answer
581 views

Are tergo-sternal muscles of cockroach involved in blood circulation?

Tergosternal muscles help in the blood circulation in a cockroach as well as in movement of the wings for flying. I came across a question that claims that these muscles are used in blood circulation ...
15
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3answers
14k views

Does any organism use both photosynthesis and respiration?

Chlorophyll and hemoglobin are very similar molecules, as far as I understand. The important difference being one using an iron atom and the other a magnesium atom. Do any organisms use both to get ...
1
vote
1answer
559 views

Cough at 1000 km/h?

How fast does air move in the airways during a cough? The following passage is from Talley and O'Connor's Clinical examination: a systematic guide to physical diagnosis (emphasis mine): Cough is a ...
0
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0answers
128 views

Mammal size and capillary wall thickness

How does capillary wall thickness vary with the size of the animal? Background/context of question: Of the following, Figure 1 is most consistent with the fact that, in general, smaller mammals have:...
1
vote
1answer
109 views

How does changing the shape of ATP synthase specifically prevent the enzyme from working any longer?

I am currently stuck on working out how to answer this question: "A random mutation causes the enzyme ATP synthase to change shape so that it can no longer function. Describe the impact this would ...
3
votes
2answers
644 views

How does air pass through when we breathe through the mouth?

When you sleep with your mouth open, does air pass through the nasal cavities? If not, how will you describe the air that enters the mouth?
3
votes
1answer
108 views

How did mitochondria make energy long ago?

I've learned that mitochondria is thought to have been eaten by a larger cell, resulting the mitochondria to be part of a bigger cell. Well, here's my Q. If you look at how mitochondria works, you ...
4
votes
2answers
2k views

Glycolysis - ATP production

In glycolysis, 2 ATP molecules are produced from each triose phosphate molecule (to give a total of 4 ATP produced; 2 net produced as 2 were initially used up in the reaction). I don't understand how ...
0
votes
1answer
2k views

Why Lungs can't work in water and gills can't work in air? [closed]

Animals-with-lungs (such as most terrestrial mammals) cannot continue breathing if merged in water, and soon die. Whereas fishes can breathe in water (at least for few-hours in case of some fishes ...
1
vote
0answers
687 views

Why does cutaneous respiration need moist skin?

My teacher told me the other week, that respiration through skin (cutaneous respiration) cannot happen without moist skin. That is why frogs have moist skin. My question- Why does cutaneous ...
1
vote
1answer
94 views

Breathing's Role in Aerobic Respiration

It's my understanding that aerobic cellular respiration is summarized in the formula $C_6H_{12}O_6+O_2→CO_2+H_2O+ATP$ (unbalanced). The glucose is thrown through a series of chemical reactions, ...