All Questions

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0answers
156 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
232 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
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1answer
707 views

Do male marsupials have a pouch?

Do male marsupials have a pouch, or is it a female organ only (like the womb)?
4
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1answer
178 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
40 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?
0
votes
1answer
456 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
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1answer
98 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
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1answer
76 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
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1answer
245 views

How do pet gecko lizards pose a health risk?

Does having gecko lizards living in your house pose any health risk?
3
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2answers
763 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
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1answer
33 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
157 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
49 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
127 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
104 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
69 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
187 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
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1answer
103 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
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1answer
159 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!
0
votes
1answer
52 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
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1answer
31 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
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1answer
222 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
121 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
526 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
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0answers
179 views

What mammalian cell lines are easiest to grow and transfect?

I'm working with HEK293 cells, which are very easy to transfect. Does anyone have other suggestions for cell lines with very high transfection efficiency? Ideally the chromosomes would also be diploid ...
1
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0answers
54 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
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1answer
34 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
533 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 ...
3
votes
1answer
44 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
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3answers
342 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
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1answer
60 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
288 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 ...
1
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0answers
36 views

Hippocampal regulation of hypothalamus

What is the difference between CA1-CA4 hippocampal subfields and dentate gyrus (DG) in negative regulation of hypothalamus? I`ve found only evidence that GR expression is more in CA1-2 and DG, while ...
2
votes
0answers
44 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, ...
1
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0answers
190 views

By what mechanism does taking a shower wake up and energise? [closed]

My personal experience is that a warm or hot shower can make me feel good, alert and energised. I've heard others having similar experiences, some mentioning cold shower as a good method to wake up. ...
0
votes
1answer
382 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
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0answers
49 views

How to use mechanical microstrainer to extract tissue proteins from human?

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 ...
0
votes
0answers
89 views

Wheat anthracnose outbreaks caused by Colletotrichum cereale in the USA

"Wheat anthracnose outbreaks caused by C. cereale were problematic during the 1940s in the USA, but presently do not limit production of this crop, despite the fact that the fungus still inhabits ...
1
vote
3answers
127 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
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1answer
2k 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
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3answers
202 views

Has medical progress stopped human evolution?

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 ...
1
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1answer
58 views

What is the disadvantage of having no anticoagulation after pulmonary embolism?

Is chronic anticoagulation always given after pulmonary embolism? What are the risks or disadvantages if anticoagulation is not given? if terminated early?
3
votes
1answer
145 views

By what mechanism is Streptococcus bovis acting as a risk factor for colorectal cancer?

Streptococcus bovis bacteremia/endocarditis is considered a risk factor for colorectal cancer. What pathophysiological mechanism may link the two together?
0
votes
1answer
576 views

Writing methods section on PCR amplication in a paper

Considering that I am writing a paper for a journal, could the following phrase be understood? or should I put the 'step-by-step' way by giving numbers? PCR Amplification and sequencing PCR ...
1
vote
1answer
56 views

What's seen when stress echocardiography shows ischaemia? Can this happen without angina?

What can be seen on the screen when stress echocardiography (a pair of heart ultrasounds before and after exercise) suggests ischaemia? Can this happen without chest pain? Illustration from ...
2
votes
3answers
1k views

Primer design for Gibson assembly

I'm trying to design a primer for Gibson assembly. My gene of interest is on a plasmid, and I want to copy that gene, and put it into a different plasmid. I am unsure how to design my primers for ...
3
votes
3answers
525 views

Why do neurones use chemical signalling at synaptic junctions?

Problem. When a neurone fires, it sends an electrical signal that jumps down the axon via the nodes of Ranvier very rapidly. At a synaptic junction, chemical brownian diffusion signalling with ...
3
votes
1answer
923 views

What is the purpose of Y-shaped adapters in Illumina sequencing?

Y adapters different sequences to be annealed to the 5' and 3' ends of each molecule in a library. The arms of the Y are unique, and the middle part, connected to the DNA fragment, is complementary. ...
1
vote
2answers
481 views

General undergraduate zoology textbook recommendation?

I am very interested in zoology,and I want to study zoology in my spare time. Any undergraduate level zoology text book recommendation?

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