2
votes
2answers
89 views

What is the difference between drought resistant non-succulent plants and plants that cannot be allowed to dry out?

What features make one plant able to withstand dry spells better than another with relatively similar structure? For instance, one of my Rudbeckias is wilting from drought at the moment, and an ...
1
vote
1answer
459 views

Breathing water vapour

Normal air consist of oxygen, CO₂ and nitrogen, with traces of water etc. Now imagine displacing all gasses except oxygen with water vapour. By water vapour I don't mean hot steam or fog. Just ...
9
votes
2answers
1k views

Does Sansevieria trifasciata really absorb Carbon Dioxide at night?

There's a claim that Sansevieria trifasciata (Mother-in-law’s Tongue) generates oxygen from carbon dioxide during the night. This seems surprising to me: that process requires energy; plants generate ...
7
votes
2answers
587 views

What effect does ambient temperature have on the cardiovascular system?

I am sorry if this is not appropriate for this site, but I think it fits so I am asking it here: I went for a run yesterday, and it was about -8⁰C. I was wearing a couple pairs of shorts, a t-shirt ...
3
votes
1answer
1k views

Does photosynthesis require only direct sunlight

I have learned throughout my basic science classes in high school that in the process of photosynthesis, plants absorb sunlight & produce food. They use carbon dioxide & water vapour. My ...
2
votes
0answers
54 views

Do humans have chemosensors for nutrients or chemicals?

I'm reading about chemoreceptors on Wikipedia, and see that the typical ones are mentioned: taste, smell, CO₂. I would like to learn more about the other kinds of chemoreceptors that humans may ...
1
vote
2answers
119 views

Plants without bacteria? is it theoretically possible?

I know from school, that all live on the Earth need bacteria as low-level "machines" that break down/extract/convert/produce chemical elements and combinations, other high-level organisms needed. But ...
1
vote
0answers
40 views

Ferredoxin synthesis pathways

I have been thinking about some alternative CO₂ fixation pathways. As almost all of them include ferredoxin reduction I started to wonder where does the ferredoxin comes from. I could not find any of ...
0
votes
2answers
90 views

How mosquitoes get their food and survive?

How mosquitoes find and get their food? For how much time they can survive without food?
0
votes
0answers
43 views

Poly Unsaturated Fatty Acid

PUFAs spontaneously oxidize, speed up the process of glycation, since too much glucose and they also decrease mitochondrial respiration - more oxygen and CO₂, less lactate and PUFA also promote ...
4
votes
2answers
128 views

Breakdown of energy expenditure at the level of a single cell

The metabolic rate measures how much energy an organism expends over a unit of time. Its breakdown for the human body in terms of its functions is well documented : so much for the heart, for the ...
13
votes
2answers
4k views

How will rising carbon dioxide levels in the troposphere affect photosynthetic producers?

Much discussion has been had about the affects of climate change on plantlife, but how will rising carbon dioxide concentrations affect the photosynthetic process itself? Since CO₂ is a reagent in ...
2
votes
2answers
47 views

Clarification on Hatch and slack pathway

The following is a minor clarification that I want to make, since it is rarely addressed directly in most of the texts I have gone through. In C₄ pathway, the chloroplasts are dimorphic, that is, ...
4
votes
2answers
263 views

Why is the floral biodiversity of grazed grassland higher than that of mown grassland?

I have collected some data to compare the biodiversity of a field in which the plagioclimax is maintained by machine mowing with a field in which the plagioclimax is maintained by sheep grazing. What ...
5
votes
3answers
233 views

Aerobic vs anaerobic respiration comparison

The following graphs compare glucose decomposition in yeasts (in anaerobic vs aerobic conditions respectively) My question is, why doesn't the first one look like a straight line as the second one ...
2
votes
2answers
103 views

Will climate change affect flower population?

There is a flower population elevated 1000 meters above sea level. If climate change causes a 12⁰C increase in temperature over the next 10 years, what will happen to the flowers?
3
votes
2answers
101 views

Ni-NTA purification, problem with the chaperone protein

I'm trying to purify the protein by Ni-NTA affinity chromatography. It seems that my protein (size about 54 kDa) is co-purified with chaperone protein (probably GroEL - as the band is around 57kDa). ...
0
votes
2answers
102 views

Why can we breathe only oxygen?

Plants has the capacity to take in both CO2 and oxygen, that's during day CO2 and at night oxygen. Why don't humans have such a capability?
2
votes
1answer
89 views

Is Hypericum Perforatum (St. John's wort) a C3 or C4 plant?

I've been curious as to which photosynthetic cycle St. John's wort uses to synthesise glucose and more complex carbohydrates. I know it probably won't be the crassulacean acid metabolism (CAM) cycle ...
1
vote
0answers
43 views

Where can I find approximate rates of sequestration of CO₂ for different species of algae?

For a study, I want to compare the rates of CO₂ sequestration and fixation of a few different species of algae. I could not find any data on the sequestration rates. Any pointers to where I can find ...
0
votes
1answer
138 views

Why can CO₂ be transported dissolved in plasma?

Is it because CO2 is more soluble in water or has it got to do with the alkaline pH of plasma ?I here mean only aqueous CO2 transport from body cells to lungs.
11
votes
3answers
1k views

Where does the 'C' in exhaled CO₂ mostly come from?

When a human being exhales CO₂, what is, by the numbers, the main source of carbon atoms exiting the body in this way? I mean what class of cells, or which tissues are the biggest on a pie chart of ...
4
votes
1answer
140 views

Does biofuel production by microalgae need an extra source of CO₂?

It is necessary to have extra source of CO2 i.e. from a nuclear reactor or factory chimney to produce bio-fuel by microalgae or is it able to do it with the normal CO2 density in the atmosphere?
6
votes
3answers
133 views

What gaseous substances do humans emit?

Other than CO₂ and Methane what other gases do humans produce or emit? For example, does skin decomposition, or aerobic respiration emit any special gases that people don't normally realize or know ...
4
votes
1answer
67 views

H₂S as a source of electrons for plants

The first electron source for plants was H2S, but now most modern plants use H2O as an electron source. What is the advantage of using H2O instead of H2S?
3
votes
0answers
44 views

Are small CO₂ concentrations devastating to certain cognitive tasks?

A new study shows strong effects of what should be a negligible CO2 concentration. The paper "Is CO2 an Indoor Pollutant? Direct Effects of Low-to-Moderate CO2 Concentrations on Human Decision-Making ...
5
votes
1answer
506 views

Total amount of CO₂ / Oxygen in Bloodstream in Humans

How much carbon dioxide and oxygen from/for respiration are in the bloodstream at any one time? (mass per litre of blood or similar) And would there be much more aside from the blood in tissue, e.g. ...
12
votes
2answers
2k views

Is there any use of CO₂ in human body?

We all know CO₂ as a waste product of metabolism . Does CO₂ have any helpful role , apart from having a role in pH of blood ?
1
vote
2answers
29 views

Are neural connections one-way?

I'm trying to think about how two neurons communicate, typically shown in pictures as an electric pulse traveling along a long, thin connective tissue. Is this depiction somewhat accurate, and if so, ...
5
votes
2answers
34 views

How do you visualize RNA on a gel?

I have run an in vitro transcription reaction and produced some RNA of a single species and definite size. I would like to visualize it to check if the reaction worked. Can I do this on an agarose ...
2
votes
1answer
28 views

Why do our epiphyseal plates close up in our late teens or early twenties?

What causes our epiphyseal plates close up in our late teens or early twenties? I realize that one's genetics plays the main role in this. I assume there is a gene that controls the epiphyseal plates ...
0
votes
0answers
41 views

How much information can a single neuron hold?

I'd like to know how much information (information that can be interpreted into thought by the brain) a single neuron can hold. I understand that memory allocation is a very complex and ...
0
votes
2answers
53 views

If DNA is the input, what is the output? [closed]

How does cells use the DNA inside them? I am looking on DNA as a strip of tape of Turing machine, but with machines its easy. I can read the tape and calculate the behavior of that machine. With cells ...
3
votes
1answer
57 views

Elevated position effect on recovery times from upper respiratory infections at rest?

In nursing school, they advice for people with upper respiratory infections to be in a slightly elevated position at the head region when sleeping. My intuition of the reason is that the lymphatic ...
2
votes
1answer
149 views

Body size, what are the evolutionary trade-offs?

Background Considering just the "Kingdom Animalia" branch of organisms. It is clear that bigger does not necessarily mean better - there is large variation in body size... From the 94 µm long ...
5
votes
2answers
61 views

Why do small organisms make faster movements than big organisms?

I hesitated to ask this question because it seems so obvious and intuitive. However, I am not able to explain this tendency. Background It seems to me that small organisms make faster movements than ...
1
vote
1answer
37 views

All or nothing phenomena

We know that an action potential is produced by an active cell membrane when the stimulus reaches a certain threshold. When it does, an action potential fires, and when it doesn't, nothing happens. ...
0
votes
0answers
45 views

How important is the womb's environment?

- Background - Talking about one phenotypic trait, the total phenotypic variance $V_p$ is decomposed into genetic and environmental variance for this trait, represented by the symbols $V_G$ and $V_E$ ...
0
votes
1answer
24 views

Could someone link me a picture of interstitial fluid?

Doing a quick Google image search doesn't return much and I'm curious to know what it looks like. Am I correct when I say, since it contains primarily lymph I'd expect it to be clear ? Thanks.
0
votes
2answers
36 views

Chromatids in metaphase?

Please see the following picture: In my book, the author claims that these chromosomes are in metaphase (a metaphase stopped by cholchicin). I don't understand why they don't have two ...
2
votes
1answer
29 views

Can the sensory neuron network and the motor neuron network be considered separate networks?

I am reading up on the nervous system using wikipedia and trying to interpret one infographic on this page: I've always thought of the human nervous system as a singular network of neurons. This ...
0
votes
0answers
8 views

Fe(II) and Fe(III) transport from rhizosphere across plasmamembrane

Does the graminaceous plants have passive uptake of Fe(II) via a passive Fe(II)-transporter enzyme? Or it it only dicots and non-graminaceous plants that have the Fe(II)-transporter enzyme? Also, can ...
0
votes
0answers
40 views

Inbreeding depression and dominance

From this article, second paragraph of the second page A classic theoretical result is that the mean of a character controlled by a single locus $i$ with two alleles $A_{i1}$ and $A_{i2}$ is only ...
3
votes
0answers
65 views

At what rate do chromosomal rearrangements occur?

How often does chromosomal rearrangements occur? i.e. what is the rate of chromosomal rearrangements? I am interested about these kind of chromosomal rearrangements that are passed on to the ...
4
votes
2answers
163 views

Why proteinase K doesn't degrade itself?

Can anyone tell me why proteinase K doesn't degrade itself? If possible please provide me the source.
2
votes
1answer
52 views

How do animals handle light refraction in different media?

For a human, when diving underwater, everything is blurry because of the water's different refractive index compared to that of air, which we are accustomed to. How do animals, like turtles, seals or ...
1
vote
0answers
17 views

Does drinking spoiled milk that has been boiled upset the GI tract?

With water, boiling will kill harmful pathogens. Does this also hold true for milk ? If it does not, what in the milk will continue to cause gatrointestinal distress ? Shouldn't boiling kill the ...
3
votes
1answer
35 views

What equation to compare protein isoforms in a Western Blot?

The protein isoforms I am interested in comparing appear as distinct bands on the gel I have already run. I have an Excel sheet with optical density measurements I obtained using ImageJ; it looks ...
5
votes
4answers
203 views

What kind of microscope for ML/biological research?

I am a computer science student, focusing on machine learning applications. I have been always interested in biology but I lack any training in it. Now, I had an idea that I could introduce myself to ...
4
votes
1answer
64 views

Gender and age-specific mutation rate in plants

Background General concept According to Cochran and Harpending (2013), mothers transmits on average a number $x$ of new mutations to their offspring. This number $x$ is independent of the age of the ...

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