1
vote
0answers
26 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
50 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
217 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
23 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
1answer
18 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
62 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
37 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. ...
4
votes
1answer
37 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 ...
2
votes
1answer
140 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
47 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
37 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 ...
2
votes
1answer
73 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
70 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
110 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
46 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
168 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 ...
5
votes
2answers
78 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
9 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
69 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
112 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
53 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
58 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
40 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
48 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
87 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
2answers
40 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
128 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 ...
2
votes
2answers
73 views

What is doubling of genetic material invented in flowering plants?

David Attenborough in his Kingdom of Plants 3D said, that flowering plants made two inventions: (1) doubling of genetic material and (2) symbiosis with animals. What was meant by "doubling of genetic ...
2
votes
1answer
63 views

What's the difference between diuretic veggies and alcohol that make the latter bad?

So I'm reading this article to Treat Fluid Retention and it suggests Eat foods with diuretic properties. But also Avoid drinks that will dehydrate the body such as tea, coffee and alcohol. ...
0
votes
1answer
23 views

Ion Channel gating

I have been studying ion channels and there is one thing i am confused about, gating between open and closed states in channels. Am i right in thinking gating is so fast that it is effectively always ...
2
votes
1answer
49 views

Could an annual plant be genetically modified to be a perennial?

My chives, asparagus, oregano, and rhubarb come back every year like clockwork. Suppose I want my bok choy to join the party - is there an "I'll be seeing you next year!" gene that can be modified to ...
1
vote
0answers
44 views

Is WIFI safe for humans? [closed]

I have wifi on at my home almost all the time. I learned that the frequency of visible light is around several hundreds of THz, while the frequency of wifi is only several GHz, which is only ...
1
vote
1answer
47 views

Source of hydrogen in reduction of oxygen in electron transport?

What's the source of hydrogen in the reduction of oxygen to water in metabolism? Is this implying that half the hydrogen comes from NADH and the other half from lone protons?
3
votes
1answer
35 views

Thrombus and Embolii

Can treatment of thrombus cause embolism, in case of very high blood pressure, that may even lead to a heart attack ? As the very high Blood pressure may cause some of the enzymes not act completely ...
3
votes
1answer
47 views

How Behind is the Human Mind (Latency of the Senses)

I would like to know if there is any research into the latency of human perception. Particulary: What is the minimum time for various inputs (vision, touch, sound) to be recognized by the conscious ...
2
votes
1answer
55 views

Where do butterflies sleep?

Do butterflies (insects) sleep, and if so, where?? I have googled for information but didn't get an exact answer.
0
votes
0answers
16 views

Reusable microarray chips

Microarray chips allow us to conduct many expression experiments in parallel to each other but they can be used only once as far as i know. Are there reusable microarray chips? Have people ever tried ...
6
votes
1answer
71 views

what is the difference between “cistron” and “gene”

I'm asking after reading the cognate wikipedia.en article on "cistron". I still am not sure about the difference of the two terms. To me it seems valid to picture a "cistron" as the genome wide set ...
2
votes
1answer
35 views

Quantitative Comparisons of Phylogenetic trees

I am working on a broad phylogenomic analysis of proteins involved in one particular cellular process. I have constructed a phylogenetic tree for each protein. I am now working on comparing those ...
4
votes
1answer
53 views

Blosum matrix with probabilities instead of the positive and negative scores

I am trying to find a version of the BLOSUM matrix that has the frequencies instead of the scaled log-odds. i.e. instead of the common version that tells us that the score LEU/ASP is -4, I would like ...
0
votes
1answer
54 views

Are harmful gases abiotic or biotic factors in our environment?

As we all know, harmful gases play a negative role in our society and our environment. Are these gases playing as abiotic or biotic factors in our lives?
1
vote
1answer
61 views

Simultaneously using both hands - How does that work?

Is some part in one hemisphere the decision maker and "calling the shots" - controlling the opposite side's hand "directly" and controlling its own side's hand through the corpus callosum. Or: is ...

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