3
votes
1answer
2k views

What is the definition of “dry weight” and “dry cell weight”?

As I understand it, the dry weight of something is its weight minus the weight of its water content. Is this the definition? What about dry cell weight?
3
votes
0answers
38 views

Adenosine metabolism

Are adenosine or its catabolites increased in inflamed airways? How can I assess this? I am trying to use inhibitors for adenosine deaminase, xanthine oxidase, and purine nucleoside phosphorylase, but ...
3
votes
1answer
128 views

Attachment of muscles during molting in insects

Normally, insects' muscles are attached to their exoskeleton but what happens to this attachment when they are moulting? Sorry if this is an extremely silly question but I have wondered about it for ...
4
votes
1answer
202 views

How does a fungus protect itself from digestion by other fungi?

If a fungus releases its digestive enzymes outside its body, how does it protect itself from digestion? How do fungi growing nearby protect themselves? I have tried searching this on google but ...
6
votes
2answers
222 views

Probability of Extinction under Genetic Drift

Here is the Wright-Fisher model of genetic drift: $$\frac{(2N)!}{k!(2N-k)!}p^kq^{2N-k} \Leftrightarrow \binom{2N}{k}p^kq^{2N-k}$$ where $\binom{2N}{k}$ is the binomial coefficient. This formula ...
2
votes
1answer
52 views

How do you estimate global species richness?

I know how estimates of species richness in a small area are made. But how do you estimate the total number of species on a global scale? One example of such a method can be found in Mora et al. ...
5
votes
2answers
500 views

Can this image be the result of a Western Blot?

I am currently researching image manipulation in the life sciences and stumbled upon a Western Blot looking very similar to the image below. For creating the image I have cut out the blot using the ...
5
votes
1answer
117 views

Competition for mates in sea horses

This source here ...research has shown that it is STILL the males that compete for females. says that male sea horses compete for mates but this source here Females exhibit a ...
2
votes
0answers
50 views

Removal of the Initial Methionine in Venus for FRET

I'm working on building some FRET reporters. In addition to a cleavage site (of varying composition from 15-18AA), a 1 AA linker, I'm using Venus and Cerulean. Initially I was worried that 18AA ...
4
votes
1answer
298 views

Are there any types of cancer that cause neurons to divide?

After birth neurons generally do not divide. But is there any specific type of rare cancer or tumour where neurons divide? And if there is such a cancer, then how is it possible for a neuron to regain ...
2
votes
1answer
707 views

What is Luc Montagnier's research on electromagnetic signals from DNA about?

After reading a Youtube comment, I started reading on Luc Montagnier's research on electromagnetic signals from DNA. I haven't been able to find a source that would clearly explain what it's about. I ...
5
votes
0answers
242 views

Genetic expression in interspecific hybrids

Referring to interspecific hybrids, I have the following two questions:- Quoting from wikipedia:- The offspring of an interspecific cross are very often sterile; thus, hybrid sterility ...
4
votes
0answers
71 views

Does DHA increase the effects of clarithromycin?

I've read on this publication that every drug that induces CYP3A can reduce the effectiveness of clarithromycin. Clarithromycin inhibits CYP3A. But it does not say anything about the opposite ...
1
vote
2answers
64 views

Protocol for measuring stamina of arthritic mice

I am going to make some mice ill with arthritis. The medicine which I am testing as control is known to cause extreme fatigue. I think I've improved it. I'd like to humanly measure their stamina in ...
4
votes
1answer
188 views

Microarray data and analysis tools

Microarray has various uses, and to analyse the data a main function classification is used. There are many methods used to classify the data but what are the best and most frequently used methods? ...
6
votes
1answer
180 views

Does knowing the sex of each of a couple’s first N children have any marginal value in predicting the sex of child N+1?

Does knowing the sex of each of a couple’s first N children have any marginal value in predicting the sex of child N+1? By “marginal” I mean predictive power beyond other known effects, e.g., the race ...
4
votes
1answer
65 views

Who was the first to talk about evolvability?

"Evolvability is the capacity of a system for adaptive evolution." (source) There are several other definitions though: Who was the first person to use the word "evolvability"? Who was the first to ...
2
votes
1answer
142 views

The concepts of relatedness - Hamilton's rule and kin selection

Here is a quotation from this wikipedia page The relatedness parameter (r) in Hamilton's rule was introduced in 1922 by Sewall Wright as a coefficient of relationship that gives the ...
4
votes
1answer
116 views

Need for proper air filter for bioreactor?

I am going to build a simple bioreactor for microalgae growth. I already have fluid filters pore size: 0.2um, diameter: 25mm https://nl.vwr.com/app/catalog/Product?article_number=514-4039 I wonder ...
3
votes
0answers
61 views

Nocioception (pain perception) in subcutaneous tissue

There seem to be no nocioceptors (pain and temperature sensitive nerve endings) in subcutaneous fat. there are nocioceptors and other receptors in veins running through fat, but these can be avoided. ...
2
votes
1answer
1k views

Transfer of antibodies in breast milk of humans

Why isn't the IgA secreted in breast milk digested due to proteases of the digestive system in the baby? Wikipedia says: The secretory component of sIgA protects the immunoglobulin from being ...
4
votes
2answers
407 views

What are the ESSs among hawks, doves, retaliators, bully and prober retaliators? [closed]

In his book "The Selfish Gene", Richard Dawkins says that retaliator emerges as an evolutionary stable strategy. But I think dove is also a kind of retaliator and so if dove increases, the hawks and ...
1
vote
1answer
625 views

Transfer of antibodies from mother to fetus

My questions: When does fetus begins to acquire antibodies from mother? Does it continue throughout the pregnancy? From Wikipedia: http://en.wikipedia.org/wiki/Passive_immunity This occurs around ...
4
votes
2answers
966 views

Microscope recommendation for an amateur?

I am a mathematics student looking for a hobby and this has come up as a potential hobby. Thus I am interested in buying a high-magnification microscope that is within the limits of my budget. My ...
4
votes
1answer
94 views

Large scale reverse transcription?

I need to make RNA:DNA duplexes. I can make 100 to 200 ug of mRNA through in vitro transcription, and I know how to use reverse transcription to make a cDNA library, but I have questions with this. ...
5
votes
1answer
611 views

What do the signs +/+ +/- mean in this image?

I don't understand what this graph is supposed to explain, especially what the signs +/+ or -/- mean. I just know it characterises some rats.
1
vote
2answers
88 views

Henrietta Lacks Cell Line - Immortality

I'm a newbie in biology and medicine. I understand that Henrietta Lacks provided the cells that formed the HeLa cell line with which much research has been done. Henrietta Lacks died of cancer. If we ...
3
votes
1answer
72 views

What makes drosophila eyes red? and is it stable?

I have Drosophila melanogaster which I am doing an eye pigmentation assay on in the future. To do this I will dissolve the heads, 10 of them removed from frozen whole flies, in acidified ethanol for ...
0
votes
1answer
1k views

Is cell membrane living

We say cell wall is dead but nobody says cell membrane is dead. Is cell membrane living or dead ? If it is not dead then why is it not included in protoplasm : Protoplasm is the living contents ...
5
votes
2answers
718 views

Can Escherichia coli survive on glucose and water alone?

I am novice to biochemistry and biology in general. I am reading Lehninger Principles of Biochemistry, and I found the following sentence at the beginning of the chapter on glycolysis: A bacterium ...
11
votes
1answer
14k views

how to close a severed artery/vein?

This is a medicine-related question that I've been wondering about. I've been watching medical lectures on YouTube regarding the human body and was wondering about how surgeons treat a severed artery ...
3
votes
1answer
135 views

Evolutionary Cell Structuring

I'm a total novice when it comes to biology, and I'm really just looking for an answer to a question that has been posed to me by people who deny evolution fervently. Evolution dictates that we've ...
1
vote
1answer
107 views

Criteria for the numbering of human chromosomes

What were the criteria devised for the numbering convention employed in human chromosomes? When was it fixed? Correct me if I am wrong; it appears that chromosome pairs 1 to 22 were originally ...
9
votes
4answers
2k views

How do trees lift water higher than 10 meters?

The atmosphere pressure is 10 meters of water (approx). This means that it is impossible to lift water higher than 10 meters with vacuum or сapillary action (on Earth, under normal conditions). There ...
3
votes
1answer
27 views

External tissues, connected to the body?

Some cancer tumors suppress themselves from spreading. When such tumors are removed by surgery, the metastasis process is accelerated. Isn't it possible to put such tumors into external device like ...
12
votes
3answers
2k views

In Japan, the official average body temperature is 36.0 °C. Why so different from that of Europe?

The Japanese Wikipedia states that the average human body temperature is 36.0 °C (here,"ヒト"). The statement references the data from the Japanese government. Actually all of my Japanese friends think ...
1
vote
1answer
176 views

Is fat distributed proportionally around the body?

One guide I have been using to tell me if I really am gaining a lot of weight is a ring around my 2nd last finger on my right hand, if I can slip it on and off without any resistance then I'm fine, ...
3
votes
1answer
491 views

Family tree for edible plants?

I am looking for a family tree for plants, particularly veg / herbs / fruit. Something similar to: If it could be slightly less technical than all the Latin ...
3
votes
2answers
154 views

How far into a pregnancy is it before visible signs of it is apparent and risk of physical trauma increases

I'm doing research for a series I'm writing. in it the main character is pregnant however goes off to fight a criminal organization who have been killing her friends and i want her appearance to show ...
3
votes
2answers
6k views

How does extracellular potassium ion concentration and calcium ion concentration affect the excitability of a cell?

When extracellular $K^+$ concentration increase by a certain amount, excitability of cells is higher because the resting potential shifts toward a higher equilibrium potential of $K^+$, therefore ...
3
votes
2answers
273 views

How does Humira work when injected into patients with rheumatoid arthritis?

OK, I have rheumatoid arthritis and I've been injecting Humira 2 times a month for the last 8 months. As far as I know rheumatoid arthritis is simply an immune system disorder which makes the immune ...
3
votes
1answer
58 views

Euthyrodism and goitre

I read in Tortora and Derrickson that goitre is associated with euthyrodism. How is that possible?
1
vote
1answer
25 views

Giving diuretics to insipidus patient

I read in Tortora and Derrickson that giving diuretics to diabetes insipidus patients may in fact alleviate the symptoms of the disease. How is this possible?
0
votes
1answer
51 views

Growth Hormone and diabetes

Growth hormone and insulin like growth factors are diabetogenic, so I assume that people with high growth hormone (say due to pituitary tumor) may be at high risk for diabetes. Has any correlation ...
8
votes
3answers
317 views

Does the Petri dish lid orientation on workbench affect aseptic technique?

When examining an incubated plate, it is rather clear that holding the plate in one hand and the lid in another is best for aseptic technique, or simply resting the lid on the plate as shown below. ...
7
votes
2answers
6k views

What determines if a gene is dominant or recessive?

Going back to my high school days we were taught about dominant and recessive genes. We were taught how to calculate the geneotype and pheneotype of potential offspring using a small table (forgotten ...
0
votes
1answer
80 views

Function of carapace

Majority of crustacean larvae have expanded carapace drawn out into processes as an adaptation for : a. Protection from enemies b. Planktonic habit The answer given is b but I think it should be ...
2
votes
1answer
307 views

Population Growth Rate Question?

A population of 600 birds faced a problem of biological magnification resulting in a large number of deaths reducing their population to 350. But 230 births also took place and 21 birds immigrated ...
1
vote
1answer
199 views

Effect of pH on life? Use buffer or HCl? How about lactic acid?

I'm trying to find the effect of pH on living things like E. coli and such. At first I thought of using a buffer solution which maintains its level of pH, but it's possible that the inactive ions of ...
4
votes
1answer
197 views

Function of papain in papaya

I know that papain is a proteolytic enzyme present in papaya. It is often used to tenderise meat. What is the function of papain in papaya? Is papain sweet? Does it function as an antibiotic?

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