4
votes
1answer
72 views

To what extent is immature eggs in insects (beetles) a good approximation for maximum fecundity?

To what extent is the number of immature eggs from dissected, newly emerged individuals a reasonable approximation for maximum/potential fecundity in insects (more specifically beetles)? I know that ...
6
votes
1answer
588 views

What happens to an ant colony when the queen dies?

Does the colony collapse? Do workers keep following the last orders? Or can future queens replace the dead one? I'm guessing this might also depend on each specific sub-species.
1
vote
1answer
163 views

What are the characteristics of a promising drug target?

When researchers are looking to start developing a drug, what characteristics do they look for in the potential proteins (assuming they already have good quality structural models)?
1
vote
1answer
90 views

Are there any examples where 'magic bullet' drugs have worked in cancer treatment?

Magic bullets are drugs that can be administered on a micro local scale. In this context administration/binding would occur in or near the tumour by exploiting the different surface antigens that ...
1
vote
1answer
57 views

What does “tumour budding” mean?

tumour budding, lymphocytic infiltration and resection margins are established factors that influence the outcome of colorectal cancer (1) In this context what does "tumour budding" mean? Reference ...
3
votes
1answer
2k views

How do liver and lung metastases cause death?

Metastasis to the liver and lungs are the main causes of death in colorectal cancer.(1) I understand that colorectal cancer may have metastases. But how do these metastases cause death? Reference ...
5
votes
1answer
317 views

Would a spinal injury decrease human height?

A woman I know has been losing height at a rate of few cm a year following a severe spinal injury. How is this possible? What kind of injury could cause such progressive loss of height? Could this be ...
0
votes
2answers
144 views

What beetle is this?

I've found it in my kitchen. It seems to be that he flew through the window from the street. The country is Russia.
3
votes
1answer
177 views

What are centromeres *really*?

I've gathered that a centromere is a a region* where the DNA is bundles up even tighter (around protein different to Histone) and chromatids are 'joined'. However I'm still mostly in the dark ...
1
vote
1answer
305 views

How does hair grow and is it similar to how grass grows?

If I recall correctly, nails (finger nails or toe nails) grow by adding matter at its base. So for instance, if you would draw a dot at the very bottom of your nail, it would end at the top in a ...
7
votes
4answers
342 views

Can sexual reproduction create new genetic information?

Is there a small chance that in sexual reproduction a new allele forms in the off-spring that was not present in either of the parents, or are the alleles in the offspring always from at least one of ...
2
votes
2answers
1k views

What is in the space between neurons in a brain?

When neuron animations are displayed, there are frequently seen neurons, axons arranged in a lattice with a lot of empty space between. I'm interested if there is indeed empty space in the brain, or ...
1
vote
0answers
240 views

Does brain activity generate heat gradients in the brain?

I'm reading this article on guiding axon growth using temperature gradient, and it mentions that the trajectory of growth of neuron connections can be influenced by temperature gradients as little as ...
5
votes
1answer
291 views

Experimental evidence for the selfish gene vs. the selfish individual

In the Selfish Gene, Dawkins makes the argument that a better view of evolution (i.e. more in accordance with experiment) is obtained if you view the basic unit of evolution to be the gene rather ...
2
votes
1answer
882 views

Do male marsupials have a pouch?

Do male marsupials have a pouch, or is it a female organ only (like the womb)?
4
votes
1answer
197 views

Reason behind formation of different shapes of cell

I have always wondered how cells are modified to give them a specific shape. On what specific part of a cell does gene regulation act for giving the shape ?
1
vote
1answer
42 views

In vitro enzyme production

I need to express a protein in vitro but I don't know where to start. I will likely do a T7 transcription protocol but for translation I am not sure what to do. Are there any good kits?
1
vote
1answer
531 views

Amino acid characteristics that determine their chemical properties?

What chemical aspect of amino acids results in their having different properties such that the chemical and physical properties of polypeptides vary with both amino acid content and amino acid order? ...
1
vote
1answer
107 views

Hardy-Weinberg applied to three alleles and stimation of allele frequencies

I have this equation: Corresponds to HW in equilibria with three alleles: $(p+q+r)^2=1$ Expanding the square results: $p^2+2pq+r^2+2pr+q^2+2qr = 1$ I need to separate homozygous and ...
2
votes
1answer
79 views

Do cockroaches eat their shells after moulting?

I recently witnessed a cockroach eat its shell after it moulted. Do cockroaches always do this?
2
votes
1answer
322 views

How do pet gecko lizards pose a health risk?

Does having gecko lizards living in your house pose any health risk?
3
votes
2answers
1k views

Ill effects of urea and NH₃ on metabolism

What exactly does urea do that harms our body? Does it interfere with our cellular processes or disturbs the colloidal onchotic pressure of our blood? I have heard that NH3 damages the brain. What ...
0
votes
1answer
34 views

First genomic survey of human skin fungal diversity

"The researchers found that a single type of fungus, belonging to the genus Malassezia, is predominant on the head and trunk. Hands, which harbor a great diversity of bacteria, are home for relatively ...
2
votes
1answer
195 views

What is this marmot-like animal (Tigray, Ethiopia)?

I was searching what are the animals I frequently saw in the north of Ethiopia. I took some bad quality pictures. For me it looked like a large squirrel, local people called it a rat, and on the ...
2
votes
1answer
56 views

What does “rapamycin-sensitive oncogenic transformation” mean?

Can someone explain exactly what "rapamycin-sensitive oncogenic transformation" is? I get that it's a drug that suppresses the immune system but what does it have to do with oncogenic transformation? ...
4
votes
1answer
147 views

Is Active Transport Required For Life?

Is active transport required for all living cells to function? I was under the impression that if a cell doesn't have active transport, it either would lose molecules through the membrane and not be ...
4
votes
3answers
114 views

Is there any source for raw data of SNP genotype frequency?

On sites like SNPedia, some pages contain the frequency of the SNP in question in different populations, based on published research. I'm trying to write a script that takes 23andme data and compares ...
4
votes
2answers
79 views

Reflexes & Pathologies including the Vagus Nerve

I only know the vasovagal reflex. I would really appreciate if someone could inform me about the other ones. About the pathologies, I already know the effects of direct nerve damage. I am talking ...
3
votes
2answers
251 views

How does the immune system distinguish own and foreign antibodies?

Therapeutic antibodies, for example Rituximab which recognises CD20 on B lymphoma cells, can cause adverse effects (e.g. http://www.ncbi.nlm.nih.gov/pubmed/19399690) One reason behind these adverse ...
1
vote
1answer
110 views

copper spiral birth control not toxic?

I Always thought that copper was toxic to the human body. So how can it be safe to place a copper object (birth control spiral) into a uterus for a duration of 5 years?
0
votes
1answer
219 views

Excretion and metabolic waste?

I know there is a difference between digestive and metabolic waste, but which one is called excretion? And what's the other one called? Thanks!
1
vote
1answer
57 views

What's food mode?

I've been watching a The Crocodile Hunter episode about Komodo dragons, and Steve Irwing kept speaking about the animals being in "food mode", in which they apparently change their behavior to one of ...
1
vote
1answer
32 views

cell uptake prediction

I'm generating random molecules I would like to know if they are able to pass through the cell membrane. Are there any ways (preferably computational) to predict cellular uptake of an organic molecule ...
1
vote
1answer
250 views

Mapping a mutation to known SNP, 3' UTR, miR

I've parsed out a very large TCGA cancer ssm (single mutation file) file to give me the essential information. The ssm is in the following format: ...
3
votes
4answers
142 views

How did the activities of protocells become inheritable?

I have learned that first a protocell came to exist and its characteristics came to be passed on by genetic material. So how come genes for all the activities come to incorporate into genetic ...
6
votes
1answer
727 views

Cat purring: What are some possible underlying mechanisms behind purring and bone remodeling and formation?

http://www.scientificamerican.com/article.cfm?id=why-do-cats-purr The article above says that cats purr mostly when they're wounded or under duress. They hypothesis that cats purring leads to ...
1
vote
0answers
61 views

Reverse complement of reconstruction model for assembling reads

One way to assemble fragments produced by DNA sequencing (often called reads) is to seek for the shortest common superstring that contains all the reads of a given set of reads. One model for this ...
2
votes
2answers
2k views

Why does the sweat of children not smell like adults?

My kids sweat plenty in this hot heat, but they don't smell afterward. I on the other hand need all kinds of deodorant. Why doesn't kid sweat smell?
1
vote
1answer
36 views

Transplantation of stem cells

During the autologous transplantation of stems cells from bone marrow to produce new blood cells why all the other stem cells other than the one obtained are destroyed?
5
votes
2answers
699 views

Can proteins move outside cells?

I am trying to learn about basic cell biology, and have what is probably an extremely simple question. So this is how I understand it so far: Proteins are made from amino acids. This process is ...
4
votes
1answer
50 views

Immunity during pregnancy

I have learnt that our immune system distinguishes self from non-self by using MHC. So a mother during pregnancy should also develop antibodies against the fetus as it is also a genetically different ...
1
vote
3answers
391 views

Diffusion across cell membranes

I got this question and don't really understand the difference between the answers. Diffusion is (in cell membrane): a) passive by nature, no metabolic energy is needed b) driven process by ...
1
vote
1answer
68 views

Is Schoons Hard Shell muskmelon a hybrid?

Would Schoon's Hard Shell muskmelon be considered a hybrid as I have read it was a cross between a Bender's Surprise and a Honey Rock.
5
votes
2answers
330 views

What medical and commercial proteins are made using genetically modified animals?

Recombinant technologies in micro-organisms being used to produce commercial and medically useful proteins like insulin are fairly common. However some proteins are still produced commercially in ...
2
votes
0answers
45 views

Endophytic Xylariaceae: diversity and taxonomy inferred from rDNA sequence analyses

"Thailand is considered as one of the areas containing a high percentage of unknown taxa of Xylariaceae (Rogers 2000). In Thailand, several studies on endophytic fungi have been documented, namely, ...
0
votes
1answer
470 views

TCGA data, and bioinformatics design questions for SNP/ mirna analysis

It's my first time posting to this forum but was looking for some help on the data aspects of this project. My tools of choice would be in python/R . Goal: I'm looking to create a disease specific ...
2
votes
0answers
53 views

How to use mechanical microstrainer to extract tissue proteins from human? [closed]

Background: There are many methods to extract proteins form human tissues out there. The majority of them use an extraction buffer containing variable concentrations of detergents and protease ...
2
votes
3answers
143 views

What kind of arthropod/animal is this?

Can anyone identify this strange creature? I live in a very urban part of Montreal, Canada. It wasn't moving (seemed dead) and although the image is huge, it wasn't as big as it seems (a couple of ...
1
vote
1answer
3k views

How difficult is to renature a protein?

I know of Anfinsen's experiments and I'm aware that some denatured enzymes may regain their lost activity through the removal of the denaturant agent. What I'm unaware of is how rare is it for a ...
1
vote
2answers
218 views

Has medical progress stopped human evolution? [duplicate]

We can cure many diseases nowadays, and thus the natural selection is very limited. Plus, mankind spent the whole beginning of its existence in almost the same hostile environment, and that's where he ...

15 30 50 per page