0
votes
1answer
10 views

Are all pathogens parasites?

If parasites are organisms that feed on other living organisms, then aren't all pathogens parasites? I've emphasised on 'feed' because I guess the pathogens just eat us (i.e. take nutrients to ...
1
vote
1answer
7 views

How do roots absorb water instead of presence of waxy - material suberin in the form of casparian strips on the wall of endodermis?

I found that in the endodermis, the tangential and radial walls have deposition of the waxy, and hence water-impermeable, material suberin in the form of casparian strips. The endodermis comes before ...
0
votes
0answers
5 views

If humans are 10cm taller than 200 years ago, then how can it be that we are “not much different” from humans 70000 years ago?

According to Yuval Noah Harari in his book "Sapiens: A Brief History of Humankind" we today are not much different from the post-cognitive-revolution Homo Sapiens which lived 70000 years ago. But then ...
2
votes
0answers
28 views

Why are lips covered with specialized skin?

I found out some interesting facts while studying our lips: They are covered in glabrous skin, while most of the skin surface is hairy; The outermost layer (stratum corneum) of the skin is far ...
3
votes
2answers
74 views

Why does all life use the same macromolecules in their genetic code?

There is no biochemical constraint of any sort, so why doesn't some other code work? Why is it specifically RNA/DNA?
-1
votes
2answers
13 views

Is agression in human males a part of sexual selection?

I have often heard that in prehistoric times, the female cavewomen would be sexualy attracted to the male who is agressive, due to this agression being some type of indicator that the male is a "good ...
-1
votes
0answers
13 views

Why are most rappers/people in music so strong (physically)? [on hold]

I noticed that lots of rappers/hip hop/reggae music performers/etc. tend to have lots of physical power. I went to a concert once with a friend and met/shook hands with Sean Paul and his grip was ...
2
votes
1answer
34 views

Metabolism priority in poisonings

Let's assume we have two toxins - one of which is routinely metabolized by the liver, and the other is new to the organism (consider for example alcohol in a heavy drinker and any other drug that is ...
2
votes
2answers
75 views

What is the distance between the sciatic nerve and the colon at the closest point?

Is it possible that a full colon impinges on the sciatic nerve? Is there anything that physically separates the sciatic nerve from the colon?
10
votes
2answers
897 views

Do males of all sexual species have Y chromosomes?

I know for instance some cells are sexual, so, this got me wondering, do the males of all species that have distinct sexes have Y chromosomes?
3
votes
1answer
20 views

Can sexual selection operate in temperature dependent sex determining organisms?

Or more broadly, are distinct forms of genetic inheritance (ie. sex chromosomes) needed for sexual selection? My thinking was that since there are no sex determining loci, there could not be linkage ...
1
vote
0answers
22 views

Differing Flow Cytometry Genome Sizes and Sexual Mating Implies Differing Chromosome Counts

Do the fundamental principles of genetics strongly suggest the following is a derived conjecture? If 2 flowering plant species A and B have widely differing genome size based on flow cytometry and ...
7
votes
0answers
61 views

Selection for less efficient egg transfer in Human Botfly life cycle

I have heard that the Human Botfly transfers its eggs through other invertebrates [1], and it strikes my curiosity that if an insect could simply land on its host directly to deposit its eggs, then ...
7
votes
2answers
89 views

Do biological phenomena follow Gaussian statistics?

I have recently entered the life sciences (from physics). I am concerned about the use of p values in the life sciences literature. For example, in this article, they test 9 - 12 rats in a control ...
2
votes
1answer
260 views

What is the biochemical reason for mental fatigue?

Is it known exactly why the brain needs sleep? What's dropping low / going high when we experience mental fatigue? I can see why low glucose could result in mental fatigue, are other reasons known?
3
votes
2answers
294 views

Can dietary monosodium glutamate intake induce restlestness?

The question is all in the title. More context: I like phở soup. I have noticed that I get restless after eating the phở soup at some restaurants. The effects are similar to the ones resulting from ...
2
votes
1answer
51 views

Is there a consensus on the CaMV 35S minimal promoter sequence?

We have an algal enhancer element and a transcription factor that probably binds it. Basal expression of the enhancer element or full promoter driving luciferase in tobacco protoplast was extremely ...
1
vote
1answer
28 views

How do we call a region of low carrying capacity?

I am looking for a convenient word to define a region of the landscape where the local carrying capacity (population size) for a given species is low but different from zero. The species is still ...
0
votes
1answer
18 views

Marker validation using transcriptome and genomic sequences derived from a single cell

I conducted a SSR marker analysis using bioinformatic tool on some RNA-seq data of human tissues. Now, my supervisor believed that we have to validate these SSR on a transcriptomic and genomic ...
-1
votes
0answers
10 views

Can anyone tell me the scope of B. Sc. Optometry & Orthoptics? [on hold]

I am new here. I just wants to know what is the scope of B. Sc. Optometry & Orthoptics? What kind of job i can do after completion of that degre?
14
votes
1answer
2k views

Why does hair turn grey or white, and why does it happen later for some?

The question is pretty simple: what is happening molecularly when hair turns grey or white? I would imagine that it is due to the lack of a particular compound. I'm also interested in why some ...
1
vote
1answer
20 views

What is the antagonist of epinephrine?

Norepinephrine and epinephrine have similar stimulant properties on the nervous system and the body. I was wondering which hormone is the antagonist of epinephrine?
4
votes
1answer
102 views

How small does a nanobot have to be to “swim through the brain” and access any neuron it wants to?

I read on this question What is in the space between neurons in a brain? that there is actually not much empty space in a brain. But my question is slightly different. Is there a visual demonstration ...
2
votes
0answers
51 views

Can flow cytometric analysis differentiate between a parent contributing longer chromosomes versus multiple smaller chromosomes? [on hold]

Given 2 closely related flowering plant species A and B in a natural contact zone where the number of chromosomes is unknown for both species assume using flow cytometry using PI staining we know the ...
14
votes
2answers
2k views

Why do only two sexes exist for animals?

Why, from the natural selection point of view, do only two sexes exist for animals?
2
votes
1answer
12 views

What is pQTL and why do we need eQTL?

eQTLs are genomic loci that contribute to variation in expression levels of mRNAs (wikipedia). There is data out there that shows that ~60% of the time, the amount of mRNA in a cell is directly ...
1
vote
2answers
24 views

How do plants get carbon?

How do plants get carbon? From air or soil? How is it different for aquatic plants and algae? According to https://en.wikipedia.org/wiki/Soil_organic_matter soil has 3.3 times the size of the ...
0
votes
1answer
64 views

Complexity in creating transgenic animals (e.g., mice)

Many papers I have seen describing transgenic rodent models (and presumably applicable to other model organisms) involve the knock-in, or modification to, a single gene, possibly two genes. With ...
5
votes
1answer
62 views

Case study and speculations on the brain of Edward Mordake

I am very interested in the case of the man named Edward Mordake who lived in the 19th century. In particular, he had two faces. If you have not heard of this man, please, search this up as there are ...
1
vote
0answers
12 views

Why is 2 sexes in an organism so common? [duplicate]

Sorry if this is a super simple question, but why do a lot of species have only 2 sexes? Some species just have 1 sex, but I've never heard of an organism having 3 sexes, for example. 3 sexes seems ...
-1
votes
0answers
12 views

Does anyone have some references on using metal halide lamps in a greenhouse? [migrated]

I am looking for some references to use Metal Halide Lamp in green house. Is there some one can recommend me the specification (also the function), brand and the supplier (if possible)?. Many thanks ...
9
votes
2answers
181 views

Should we induce fever to assist healing?

I am currently reading "The Fundamentals of Anatomy Physiology" 10th edition, and have found it an incredibly interesting book. I have just been reading about the lymphatic system, and the various ...
1
vote
1answer
20 views

genes map to eQTL/pQTL

Of the 192 target genes, 79 map to a significant eQTL or pQTL in at least one dietary condition. is the line for a paper "Multilayered Genetic and Omics Dissection of Mitochondrial Activity in ...
0
votes
2answers
25 views

What would happen if most the fat in your body was rapidly converted into energy in 2 minutes? [on hold]

It all started out as an argument I had with my friend.He said that "it would be the equivalent of catching a fire and burning" But all I thought would happen is that you would now be very hyper ...
1
vote
1answer
22 views

How to validate the use of an anti-virus monoclonal antibody in IHC by spiking a fresh organ with infected cultured cells?

I have assessed the specificity of a particular monoclonal antibody against a virus by immunofluorescence. I'd like to further validate it by testing it by IHC. Therefore I'd like to infect cells in ...
0
votes
0answers
26 views

Do we all dream “every” night?

I had an argument with my brother and he claims that he doesn't dream every night ie when he dreams he always remember and if not he hadn't dreamt at all. I'm under the impression that all humans ...
3
votes
3answers
82 views

What is a good source that will help me classify protists?

I am a 15 year old that enjoys looking at the micro world. The only issue that I have is that I can't find a good online source that will help me classify the name of the micro organism that I'm ...
1
vote
0answers
25 views

What neuro-motor diseases cause the lower esophageal sphincter (LES) to malfunction?

Please note: This question is neither homework nor seeking medical advice. I'm simply asking for a factual, objective, biological explanation of the various neuro-motor diseases/illnesses that can act ...
0
votes
0answers
10 views

Size of the glycan chain in a glycosylated protein

I would like to know where I can found the (experimental/estimated) distribution of glycans sizes attached to proteins.
-2
votes
0answers
15 views

Why do we stop growing even if our cells continue to divide? [on hold]

Why do we stop growing after a certain age while our cells are still dividing?
-3
votes
0answers
12 views

How does the SA node self excites itself? [on hold]

It is written in my book that SA node is self excitatory in nature ? How does it self excites itself ?
3
votes
2answers
152 views

Is it possible to pet/groom birds?

I wonder if it's possible to pet a domestic crow, or an owl. Do birds respond to grooming as cats or dogs, for example? If so, then how does one pet a bird?
0
votes
0answers
11 views

Nicotine and plants [duplicate]

I hear that nicotine, produced by Nicotiana tabacum, is poisonous to the plant itself, which is why it accumulates the nicotine in the central cell vacuole. If so, why is nicotine produced in the ...
0
votes
0answers
10 views

How do non-dimorphic birds distinguish sex of possible partners/rivals?

Some birds, such as my pet Pionus chalcopterus, are not sexually dimorphic. People can't tell them apart, and even trained avian vets are not 100% certain with an inspection probing the vent. I ...
-1
votes
0answers
12 views

Effect of cytokines on dengue virus [on hold]

I want to know what sort of effect the following cytokines would have on dengue virus: IL-1β, IL-10, PAF, S1P, and TNF-α. 1) What sort interactions do they have? That is how one cytokine ...
0
votes
0answers
12 views

Proteins denaturation and natural selections

Which are the advantages, in terms of natural selection, of the denaturation of the proteins during the food preparation? Or in other terms, is it more important the reductions of bacteria in the food ...
0
votes
1answer
14 views

What is the “leaky valve” between the esophagus and stomach?

When someone talks about there being a "leaky valve" between the esophagus and the stomach, what is the exact biological structure they are talking about? This would be a structure that, when ...
1
vote
2answers
23 views

What exactly is extreme heterozygosity and how does it work? [on hold]

Of course, I know in reference to apples. I also understand homozygous diploid pairs, like pp or PP, and heterozygous pairs like pP and Pp, and hetero/homozygous dominance and recession all that good ...
4
votes
1answer
21 views

How long is saliva viable?

Does anyone know if saliva can stay viable for about 5 days, before it gets suspended into a DNA genealogy vial for testing? Background: My brother wants to do a DNA genealogy test at a US testing ...
10
votes
2answers
2k views

Do birds emit infrared?

I'm an electronics engineering student and I am going to use a sensor that detects infrared emitted by birds that invade rice paddies. My question is: Do birds emit infrared radiation? I know that ...

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