1
vote
1answer
36 views

Reverse tomography to create 3D scalpel

Isn't it possible to reverse tomography methods to create means to deliver heat or radiation precisely in 3D? This would be "3D scalpel" i.e. device which would be able to eradicate tumor cells ...
0
votes
1answer
22 views

How many systemic reactions in inflammation?

I have this sentence in my notes Inflammation consists of two local reactions and one systemic reactions. which is difficult for me to accept. Two local reactions are vascular and cellular. I ...
2
votes
2answers
56 views

Clarification on Hatch and slack pathway

The following is a minor clarification that I want to make, since it is rarely addressed directly in most of the texts I have gone through. In C₄ pathway, the chloroplasts are dimorphic, that is, ...
1
vote
2answers
48 views

Multicellular organisms as DNA banks

Animal -> bacterial gene transfer seems easier than bacteria -> animal (rotifers are an interesting exception); there are bacteria live in close contact to us but our germ-line cells are protected. ...
0
votes
1answer
34 views

Why do doctors do chemo or transplantation for cancers that don't respond well to these treatments? [closed]

From the UpToDate article on multiple myeloma: In most people, chemotherapy partially controls multiple myeloma; rarely, chemotherapy leads to complete remission. Also: Transplantation, ...
3
votes
2answers
73 views

Why do humans circulate monosaccharides instead of disaccharides as in plants?

Plants transport food mostly in the form of disaccharides like sucrose but humans transport them in the form of a monosaccharide - glucose. What is the reason behind this ?
-1
votes
1answer
207 views

What is the benefit of using Gonoline-Euroline in combination? [closed]

I was heard that this combination first Gonoline and other culture another culture on Euroline is good one. What is the benefit of using Gonoline-Euroline in combination?
1
vote
1answer
32 views

What are the best detection medias for cholera?

I heard this fact that you can use some [hypertriade] for vibrio cholera diagnosis which has compontents sucrose (yellow) mannose (yellow) arabinose (do not ferment; stay dark pink) I did not find ...
0
votes
2answers
87 views

What is the right spelling for this agar? [closed]

I could not spell the agar [gonoline-uroline] which I heard yesterday. My spelling is so wrong that I could not find it in Google. What is the right spelling for this agar?
2
votes
5answers
232 views

Does a neuron ever generate an action potential without stimuli?

Most accounts I read involving action potentials and synapses and the like tend to focus mostly on the action potential as a mere automatic reaction to another similar event happening upstream. From ...
0
votes
3answers
483 views

Why do we exhale after we hold our breath?

I tested this out with my friends, and I find that after they hold their breath and can't hold it anymore, they exhale air, instead of inhaling air. Interestingly, they all try to inhale in as much ...
0
votes
1answer
38 views

Shigella's O antigen (PAI synthesised) and passage through host defences

The O antigen is synthesised by Pathology islands (PAI). O antigen may be a factor why Shigella survives the passage through host defences. I am interested in which step of pathogenesis. There are ...
2
votes
1answer
40 views

GULO only for mammals?

I am not a biology student, but just want to know if GULO gene are present only in mammals or all species possess it ? And is GULO gene active in human fetus?
0
votes
0answers
37 views

Can we define biological age? [duplicate]

How can we define ageing from a biological standpoint without making an appeal to chronological age? Related, but less important, are there any metrics we can use to determine someone's biological ...
6
votes
1answer
99 views

Hill-Roberston effects and effective population size

From this article, first page, middle of the second column: Even if harmful alleles do not become fixed, they can still reduce the efficacy of selection on neighbouring loci through a process ...
1
vote
2answers
61 views

Can viruses be used to extract oil from algae?

I read that one hard step in algae oil extraction is to rupture (or fracture) the cell walls to get the contents inside. Some people use chemical methods; some use sonication or mechanical forces. I ...
2
votes
1answer
1k views

Isopropanol precipitation of DNA - duration and magnitude of cold storage

DNA prep protocols often include a final precipitation step with alcohol, often isopropanol, where the DNA must be kept in the alcohol, at a low temperature such as -20C or -70C, often overnight. ...
3
votes
1answer
156 views

Meiosis vs. Mitosis

Meiosis is a type of cell division that reduces the chromosome number from 2n to n to make gametes viable for reproduction in humans. I know that during meiosis, there is independent assortment and ...
2
votes
1answer
92 views

Does recombination increase the additive genetic variance for fitness?

On this article, first column, eighth line of the introduction: By bringing together favourable alleles from different chromosomes, sex and recombination increase the additive genetic variance for ...
1
vote
1answer
31 views

What indices can we use to describe fitness landscapes?

We usually talk of smooth or rugged fitness landscape. Are there any (standard) indices to measure the "structure" of fitness landscapes? For example, one might consider the mean epistatic ...
4
votes
1answer
1k views

Rate of cell division in humans

On average, how many cells divide each day in a human being? How long does a cell wait before dividing itself ? I have tried to look on the internet but surprisingly the answer is difficult to ...
2
votes
2answers
127 views

Primer design and BLAST E value stringency

When searching for misprimings I have been told that an e value that is higher than 0.01 is ok and will produce no significant amounts of mispriming. Yet I searched some and it would seem that the e ...
0
votes
1answer
216 views

Difference between Cary-Blair and Amies transport media for Staphylococcus and Streptococcus?

I normally use Amies medium, but I today heard that Cary-Blair is also possible. When should you use Cary-Blair medium?
2
votes
2answers
783 views

Why there is a very high drop in pressure from arteries to arterioles?

Laplace law explains why the pressure is the same in aorta and arteries (100). I am thinking why there is so big drop in pressure when going from arteries to arterioles (40-60). Why there is a great ...
1
vote
1answer
57 views

Genome Assembly Using Reads

I'm taking an online bioinformatics class and I am stuck on a problem. The resources I have found don't help that much. Here is the problem: "Assemble the error-free reads from a circular genome on ...
0
votes
2answers
111 views

Systemic sensory confusion?

Sometimes when a person gets touched on one part of the body they feel it else where and may think it came from a different part of the body. What causes this? Other examples are similar to why you ...
1
vote
1answer
28 views

Difference between Fulminant and Acute Meningococcemias

Fulminant seems to mead rapid. There is however some articles with both phrases: "fulminant meningococcecemia" (about 5000 Google matches) and "acute meningococcecemia" (about 3000 Google matches). I ...
2
votes
1answer
39 views

What's the best way to measure/calculate the size of a light beam at the sample of a microscope?

I am using a microscope with an LED derived light through the epi-fluorescent port of a microscope. I know that the "field of view" for a given objective is equal to the field number/magnification ...
3
votes
2answers
228 views

How does the brain know where a signal came from? What is the addressing system

I am an electronic engineer so I am thinking about this from an electronics outlook. How does the addressing system work, As I see it, the nervous system is small parallel branches attached to larger ...
0
votes
1answer
16 views

Is Rheumatic fever more Chronic than acute?

It follows from the complication of S.pyogenes' pharyngitis. I am thinking how the inflammatory response behaves: acute or chronic or something between. I think chronic disease is better description ...
0
votes
1answer
66 views

M-type potassium channels by muscarinic receptors

How does the closure of M-type potassium channels by muscarinic receptors result in increased excitation of the target neuron?
0
votes
1answer
132 views

Pathway mediates nitroglycerin-induced relief from angina pectoris [closed]

what kind of Pathway mediates nitroglycerin-induced relief from angina pectoris,please provide some idea...
1
vote
0answers
63 views

Best way to automatically link Gene Entrez ID with Gene Symbol in TCGA

I am trying to figure out how to link Gene Entrez ID with Gene Symbol, for TCGA dataset. So far, I have found this ftp directory with Gene info updated daily. But, for Entrez ID 728661, I have found ...
0
votes
3answers
89 views

Phylogenetic tree

I want to find the conventional phylogenetic tree of human, mouse, C elegans and drosophila, without all the other organisms. Do you know where can I get it? thanks, Noga
0
votes
1answer
25 views

Is endoderm visible in the germ layer?

This picture is my drawing about germ layer - not embryonic folding as I wrote initially. Where exactly is the endoderm here in the picture? The known things Ectoderm Neural tube Notochord ...
4
votes
1answer
82 views

Does adding milk to cereal make it harder for our body to absorb the vitamins and minerals from the cereal?

I add about 3/4 cups of Blue Diamond almond milk (unsweetened) every morning to a single serving of Cheerios. The milk contains filtered water, and I read that drinking water with food at the same ...
-2
votes
1answer
63 views

Why do mammals in the wild retain the “trait” of menstruating with blood?

This question intrigued me a lot since if animals in the wild did have menstruation with blood flow, wouldn't all that blood be attracting every other predator in the vicinity?
2
votes
1answer
94 views

Solubility of Forskolin in ethanol

I am interested in using forskolin in cell culture medium. Does anyone know how to make solution of 10 microM forskolin in 5% ethanol or less. I would like to avoid using DMSO as a solvent. Thank you. ...
0
votes
1answer
51 views

How do neurons send electric pulses even though they are surrounded by liquid which is mostly water?

I just thought about the fact that people move through electrical pulses traveling through neurons in the brain and muscles through the body. Here is what i know: the body is full of 97 or more, ...
3
votes
1answer
33 views

Prevalent large (>=90kDa) maintenance protein/loading control

I was wondering if anyone had recommendations for good, large (hopefully 100kDa+), control proteins that would be present in most mammalian cells. I'm working mostly with tissue samples from humans ...
5
votes
2answers
277 views

Why is Portuguese man o' war considered a colony?

The wikipedia entry on the Portuguese man o' war says: ... the Portuguese man o' war is ... not actually a single multicellular organism but a colonial organism made up of many highly specialized ...
1
vote
2answers
98 views

Smoking, cancer, correlation between quitting smoking and increased immediate risk

There is "proof" out there today that suggests smoking is directly linked to cancer. I cannot argue against that, for the evidence in favor appears strong, and the evidence against is lacking. I'll ...
2
votes
1answer
81 views

Mutation rate in viruses

Mutation rate is a phenotypic trait that evolves. The process of evolution of such kind of traits are often referred to as evolvability. I am wondering about the evolution of the mutation rates in ...
0
votes
1answer
29 views

Which direction are wild beehives combs oriented?

Is it on the North-South axis, the East-West axis or some other orientation?
1
vote
2answers
69 views

Aren't current explanations for the evolution of human cooperation a little too reductionist?

Lately, I've become a believer in the limits of reductionist explanations especially in areas like complex systems and biology. So, without wasting any more time, I'll get to my question.. Whenever ...
2
votes
1answer
40 views

Do vitamins help our memory?

It is commonly believed that vitamins can help our memory. Is this really true? What is the biological basis of this? Is there any specific research paper on the subject?
0
votes
2answers
123 views

DNA sequence from the middle of a gene

Someone gives you a short DNA sequence that comes from the middle of a gene. 5'- TCTAACTGATTAGC -3' 3'- AGATTGACTAATCG -5' From this sequence, determine the ...
0
votes
0answers
132 views

Genetic Linkage/Mapping question Help

Hello everybody! I need some help with this question in the image posted. As you can see in the instructions, I'm asked to map the genes. So the first thing I did is write out the alleles ...
0
votes
1answer
60 views

Why prefer $MgSO_4$ over $MgCl_2$ in recipies [closed]

Many molecular biology recipes use MgSO4 (and not MgCl2). Is there indeed a preference? If so, why?
-1
votes
1answer
361 views

How to convert nanogram to picomole? [closed]

I have lets say 10ng/uL of RNA. How can I convert it to picomole? I need it to calculate how much magnetic beads I need. This is the product: ...

15 30 50 per page