3
votes
1answer
33 views

What is the purpose of back-crossing mice for multiple generations?

Occasionally I will come across articles that refer to back-crossing mice of one strain onto the background other another strain (e.g., C57Bl6). They do not explicitly state the purpose for doing so, ...
1
vote
1answer
51 views

Is it possible for neurons themselves to manifest cancerous behavior?

From what I understand, one form of cancer is a faulty gene responsible for the programmed death of a cell. Not long ago, popular wisdom used to say neurons don't regenerate. However that is no ...
1
vote
1answer
65 views

Has any creature ever devolved to be cold blooded? [closed]

Is this even possible? Because I have a non-scientific gut feeling that it is irreversible. Whales and dolphins are evolved from land mammals, and they've remained warm blooded while it doesn't give ...
3
votes
1answer
30 views

Loss of allelic variation per generation of full-sib mating

If we take a male and female, cross them, and collect one son and one daughter to produce the next generation (and continually do this for many generations) - (full-sib mating design) how much genetic ...
4
votes
3answers
68 views

E-value BLAST cut-off

What is the best cut-off for e-value in BLAST? Some say 0.01 ,others 0.0001? Even BLAST tutorials don't give a very clear idea about which cutoff suits which purpose? Could some experts give me a ...
0
votes
0answers
17 views

What models are used for the different pathways of apoptosis?

We are trying to find references for experimental models of different pathways of apoptosis (caspase-dependent and -independent intrinsic apoptosis, death receptor type-1 and -2 mediated apoptosis, ...
0
votes
2answers
41 views

Why are we carbon-based?

Is that because of evolution? Does it have something to do with its amount in the universe? Carbon compounds form the basis of all known life on Earth, and the carbon-nitrogen cycle provides some of ...
4
votes
1answer
58 views

What Proteins Are Universal To All Life Forms?

According to National Geographic, there are 23 proteins that are common to all life forms: All species in all three domains share 23 universal proteins, though the proteins' DNA ...
1
vote
0answers
34 views

List of Asymmetric Animals

The (male) Fiddler Crab is a famous example of an animal whose morphology exhibits neither mirror nor radial symmetry: (Image source) List of animals featuring external asymmetry is a Wikipedia ...
3
votes
0answers
38 views

First RNA polymerase-mRNA

We know that RNA polymerase produces mRNA by reading DNA strand.Which enzyme produces the first RNA polymerase if other RNA polymerases are synthesized in the same way like other enzymes(proteins)?
2
votes
2answers
65 views

Essential amino acid codons

Essential amino acids also have codons.Still they are needed by humans through diet?Will those codons do synthesize amino acids for some other purposes in humans or not?If so, what is the purpose?e.g? ...
3
votes
1answer
74 views

How much DNA of Albert Einstein is recoverable?

Since there seem to be five biological descendants of Albert Einstein, and the original chromosomes of him distributed among them ... Is it possible to recover enough DNA of an individual from his ...
3
votes
2answers
1k views

Why aren't animals diverse in phenotype? [duplicate]

I am not comparing a cat with leopard. I am just saying that we humans are all one type of creature and we are diverse (I am not saying we are class of mammals and phylum of etc and kingdom etc, ...
4
votes
2answers
45 views

Are all mutagens carcinogens?

Not all carcinogens are mutagens. Alcohol and estrogen, for example, do not damage DNA. It's one of the assumptions of the Ames test that mutagenicity implies carcinogenicity, but is this always the ...
1
vote
0answers
21 views

Weinman AIF and High temporal resolution AIF difference

I'm dealing with MRI DCE maps. Actually I need to find such parameters as the transfer constant $K^{trans}$ and rate constant $k^{ep}$ according to the two-compartment model. Mathematically, this ...
2
votes
0answers
36 views

Software to calculate Fst from sequence data

I'm looking for a software to calculate Fst from 3 loci DNA data of individuals from a metapopulation. I don't have any prior on the population structure (have no idea of the number of subpopulations ...
5
votes
2answers
193 views

What does irregular heartbeat mean in simple language?

I bought a blood pressure monitor (A&D UA-851) which has the option to measure irregular heartbeat. I do understand what 'irregular' means, but why do irregular heartbeats happen and what are ...
0
votes
0answers
19 views

Is it possible to synthetically replicate the results of cryptobiosis? If so, how?

Okay if my question seems ridiculous I apologize because I have next to no knowledge of synthetic biology and what the field is capable of doing and it's methods and methodology. Take a organism ...
1
vote
0answers
57 views

Can human change its morphology or anatomy due to ecological changes?

According to Charles Darwin, as the surrounding environment changes, so changes the anatomy or morphology of a specific organism. But nowadays, humans have become very advanced in the technology and ...
1
vote
2answers
47 views

Useful physical information of a protein

Beside energy and heat, I don't know any useful physical information of a protein. Can you help me list some of it. Somethings like Fourier-transform infrared spectroscopy to provide protein structure ...
0
votes
1answer
22 views

Biosphere that simulates sun and moon shifts

Is there an enclosed biosphere that artificially simulates the movement of the sun and moon at increased intervals? It is known that the sun and moon alter plant movements therefore I was wondering ...
0
votes
0answers
24 views

Basic chemistry of the Shinoda test for flavonoids? [migrated]

In this test, four pieces of magnesium fillings (ribbon) are added to the ethanolic extract followed by a few drops of concentrated hydrochloric acid. A reddish colour indicates the presence of ...
0
votes
1answer
17 views

Simple experimental design of a chemostat without pumps

A chemostat is a device to maintain a cell culture in equilibrium, by continually pumping nutrients in and pumping excess cells and nutrients out. What's the simplest design of a chemostat one can ...
2
votes
1answer
59 views

Senescence, immortality and evolution?

Many have heard about the fabled "immortal" jellyfish, Turritopsis dohrnii, which doesn't die from aging (senescence) and can revert the aging process indefinitely. It is rather remarkable that only ...
2
votes
0answers
33 views

What causes headaches (biologically)? What does it mean directly? [closed]

Even though your brain can't feel pain, thingies in your head are installed to compensate for that. Once I thought your head starts to hurt when your brain is tired. I can't believe this any more. ...
3
votes
1answer
31 views

How can Taenia solium (tapeworm) lay 35,000 eggs per proglottid?

As far as I know TAENIA SOLIUM is an acoelomate which basically means that the space between the alimentary canal and the gut is completely filled [or] occupied by the mesoderm and they do not have ...
0
votes
1answer
133 views

what is the margarine metabolism in our body?

margarine is commonly used food ingredients that contribute to both inflammation and obesity , but actually I want to know the margarine metabolism in the human body I can find some resources talk ...
4
votes
1answer
38 views

Why does max heart rate decrease with age?

I have heard that max heart rate declines steadily with age, and can be approximated by the equation Max Rate = 220 - Age. What is the physiological reason for this decline, and how is it ...
2
votes
1answer
35 views

Which of the following demonstrates the pattern of development in Greylag Geese?

Which of the following demonstrates the pattern of development in Greylag Geese? {Please give specific answers, which among the following gives the best available demonstration?, If needed, have a ...
1
vote
1answer
65 views

What Aquatic Mammal has no Tail?

Found in a waterway in Butte County, CA. First thought it was a beaver kit, but it has no tail. What aquatic mammal has no tail?
1
vote
1answer
66 views

Is it possible to get infected with HIV from old blood?

Let's say that someone uses a needle which has some old blood infected with HIV. In this case, is it possible for them to get infected with HIV?
1
vote
2answers
103 views

On evolution statistics [closed]

This basic evolution theory question has been haunting me since childhood and I'm kind of embarrassed that I can't explain it yet: Consider a butterfly. It's wings have evolved to look like the eyes ...
0
votes
1answer
44 views

can psychology of a person alter his immune system and health?

I just want to know that can psychology of a moderate aged person alter his immune health because I have read many a times about the different types of linkages between nervous system and immune ...
4
votes
1answer
162 views

Is there an 'anti-virus'?

A virus spreads around and usually attaches itself to the host, multiplies & causes diseases. But is there something like an anti-virus? A single celled entity that does the opposite: spreads ...
1
vote
0answers
32 views

What's the smallest organism that can produce voice?

What's the smallest organism (animal, insect, or any living creature) that can produce voice. And not just make sound, but has an organ to specifically to create sound, like how us mamals have vocal ...
0
votes
0answers
8 views

Cell volumes of the MDCK, COS1 and ECV standard cell lines?

Where can I find information regarding their volumes? In general where can I find information regarding common cell types?
2
votes
1answer
64 views

How do some plants grow in salt water, while others die?

My question is basically out of curiosity and comes from observing how certain plants (such as mangroves) can grow in seawater. If this gives the plant an advantage, why haven't all plants that grow ...
-2
votes
1answer
30 views

What is the smallest known organism with a skeleton? [closed]

See question title. After doing some looking around on my own I haven't found much so I figured I'd ask some experts.
1
vote
2answers
81 views

Which organs do cats not eat on their prey?

My female cat is a very active hunter and brings me her prey daily. Except for shrews and birds, she always eats them entirely. This afternoon she brought me this: It was quite large (maybe ...
2
votes
0answers
34 views

How can cells produce antibodies despite error-checking mechanisms in their genomes?

How can immune cells produce so many different kinds of antibodies with different variable regions if there are so many mechanisms inside the cells that try to keep the DNA sequence as constant as ...
0
votes
2answers
26 views

How to find a PDB structure of a protease with a peptide like inhibitor

I wonder how, for purposes of just illustrating some concepts like substrate alignment in the catalytic triad active site, I can quickly and efficiently find a protease structure (irrelevant of what ...
1
vote
0answers
20 views

Are there critical points in ecosystems?

Some days ago, I was thinking (partially) about the complex balance that is needed for an ecosystem to exist. I got curious about the existence of some sort of critical point, something - that when ...
3
votes
3answers
49 views

what are good sources of free-to-use images and diagrams

I am looking for good image repositories for biology teaching. Photos and textbook-like diagrams. I am interested in images that can be used commercially without payment, or, at least, that require ...
0
votes
0answers
50 views

Ribosomal Turing Machines, DNA/RNA computation

I'm a computer science guy, recently crossing over to do some research in computational biology on RNA secondary structure prediction. While looking through the materials I got a crazy idea, what if ...
3
votes
0answers
39 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 ...
1
vote
1answer
34 views

Carbon Monoxide and High-Oxygen-Affinity Varieties of Hemoglobin

I recently learned about the concept of "affinity" in regards to hemoglobin. For hemoglobin in humans, carbon dioxide has a lower affinity than oxygen, which allows gas exchange to occur in our lungs. ...
1
vote
2answers
43 views

Is epimysium same as fascia?

I have read that epimysium is dense regular connective tissue made covering the a muscle like bicep brachi. at the same time we have fascia that is made of dense regular tissue and covers muscles. so ...
5
votes
1answer
63 views

Which part of human eyes is getting tired?

It's a thing of common sense that if you read, drive or look at computer screen for too long your eyes will get tired. They burn, itch and try to close all the time. But I was wondering which part(s) ...
2
votes
3answers
37 views

TB disease - treatment and infection

Background: I'm currently performing research in mathematical biology, specifically on the treatment dynamics of HIV and TB co-infection. Question: Can a person infected with TB disease, who are ...
3
votes
2answers
124 views

How is information sent from limbs to the brain exactly?

Say you have a needle, and you poke a very specific area on your left thumb. A signal gets sent from that nerve up your spine and into your brain. How does the brain know exactly where this signal ...

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