7
votes
1answer
145 views

What makes a wet dog so stinky?

Similarly, what makes a wet down comforter so stinky? Why do they make no smell except when liquid is added?
6
votes
2answers
195 views

Can I compare Shannon indices of metagenome gene data?

I'm comparing 12 Metagenomes. I'm using HMM counts of a number of proteins known to exists as groups within certain operons. I have grouped the HMM counts for each type of operon and calculated the ...
8
votes
1answer
426 views

How many gigabytes of DNA are there on earth?

The human genome is about 770 MB, the C. elegans genome is about 100 MB, the yeast S. cerevisiae is about 12 MB. Different other genomes have been sequenced: how many GB of genomic DNA we have now? ...
7
votes
1answer
192 views

Why are some menstrual cycles irregular?

A friend of mine asked me this today, and I didn't know. I remember studying the menstrual cycle a few years ago, but I can't remember the details (other than it was very hormone-related), and so I ...
4
votes
1answer
504 views

Why are omega-3 fatty acids so easily oxidized when they're incorporated in cellular membranes?

Apparently, this has led to results with clinical significance, as we can see at http://extremelongevity.net/2011/10/03/daily-fish-oil-consumption-may-reduce-lifespan/... The researchers fed a ...
5
votes
1answer
96 views

Reproduction and defecation

In mammals and birds the external reproductive organs and waste removal organs see to be the same. Is this always the case with other animals such as insects etc...? Are there any good reasons for it? ...
6
votes
1answer
44 views

harvesting fertilized eggs from Tetraodontidae species?

I would like to know how easy/difficult it is to harvest fertilized eggs from Tetraodontidae species such as Tetraodon nigroviridis or Takifugu rubripes compared to zebrafish? Ultimately, I would like ...
7
votes
1answer
932 views

Is it possible for any animals today to have more than one brain?

Is it possible for any organisms in the animal kingdom to have more than one brain?
5
votes
2answers
488 views

Did dinosaurs have more than one brain? If so, why?

I once remember reading (15 years ago) that dinosaurs had two brains. One for their head and another one for their digestive functions. What is the current opinion on this theory? Has more evidence ...
5
votes
1answer
1k views

Do hot drinks cool you down?

It is quite the old wives tale that drinking a hot drink cools you down. If you don't really think about it it does seem somewhat logical: increasing temperature will cause your body to try and cool ...
4
votes
1answer
241 views

Can humans shorten their sleeping patterns?

Can sleeping patterns be trained, or are they genetic? I read that a human needs to sleep at least 4 hours. Can sleeping time be reduced without having a negative impact?
3
votes
0answers
24 views

What metabolically happens when an egg fuses with the nucleus of a somatic cell

In stem cell biology, it is recognized that embryonic stem cells are transcriptionally inactive for the first 3 days of development. However, during somatic cell nuclear transfer, the nucleus is ...
2
votes
2answers
180 views

How might I break down bread into glucose in a model of the human digestive system?

I need to make a model of the digestive system. It would be really nice to actually show it in action, such as by breaking down bread into glucose or something similar. Is this feasible with a small ...
0
votes
1answer
183 views

What is the similarity between how cells organize themselves to form a human and how humans organize themselves to form a society? [closed]

Some things I have gathered. Common properties - individuals - communicate - local view - selfish - specialize - organize - replicate - cooperate - emergence Terminology cell ...
4
votes
1answer
145 views

Vigorous shaking for HFR interrupted mating

I am trying to reproduce E. coli interrupted mating using an HFR strain, and I read that the cultures should be vigorously shaken at times to interrupt the DNA transfer from the F+(HFR) donors to the ...
0
votes
1answer
118 views

Herbal vs Chemical Insecticides [closed]

Well, insecticides are used to kill insects. I have always wondered why are herbal / natural insecticides more effective in killing insects than chemical ones. I have read this at many places but ...
5
votes
1answer
168 views

What is an simple way to burn glucose for visible effect?

I want to make a partially working model of the digestive system that could digest complex carbohydrates. My ultimate goal is to be able to cut up some bread, put it into the model, operate it, and ...
8
votes
1answer
233 views

How Antioxidants affects Human Metabolism?

I'd like to know how antioxidants affects the human metabolism and which ones are essential for metabolism processes.
6
votes
2answers
73 views

Macrophage pathogen fixation

Overly simplified, macrophages recognise pathogenic patterns and endocytose anything that matches them. That also works on bacteria, which are quite often very mobile. What if a bacterium was just ...
3
votes
1answer
325 views

Mechanism of Tear Gas (chloropicrin/Trichloro methane)

Tear gas (CCl3NO2) makes people cry, and crying doesn't seem to be a simple procedure. There has to be a triggering process somewhere. Can someone explain its mechanism / how it works?
9
votes
2answers
825 views

Databases for gene regulatory network graphs?

What databases are available for gene regulatory network graphs starting from a given gene? For example, starting from p53 gene, where can I find a gene regulatory network image that can be exported ...
4
votes
1answer
2k views

Co-transformation of plasmids from the same incompatibility group

Can two plasmids with the same origin of replication (for example pBR322 ori) and thus from the same incompatibility group be successfully co-transformed in E. coli? What are the mechanisms that would ...
7
votes
1answer
270 views

Skeletal muscle without antagonist

Is there any skeletal muscle that does not have an antagonist? Excluding circular muscles such as around eye and mouth. The reason why I am wondering is because in biology normally nothing is ever ...
4
votes
1answer
63 views

Productive turnover and generations in the fruit fly

I was reading about the Lenski experiments on the evolution of E. coli bacterium and Dr. Elders's experiments on the evolution of the guppy. These two experiments absolutely fascinated me, and seemed ...
7
votes
2answers
215 views

Does becoming martyr have an evolutionary advantage?

This is related to How does "be altruist to those who are similar to you" evolve? Altruism that is Not reciprocal Not familiar has little explanation. One possible explanation is that ...
9
votes
3answers
11k views

Healing process in mouth wounds

When we have an external wound the wound generally tents to clot and there is a layer of solid scab formed. Now,Yesterday while brushing my teeth i somehow hurt my gums and it got all bloody but ...
1
vote
0answers
162 views

Is whey-protein folding an example of micelle in water? If not, what is it?

I can find a lot of information about protein folding in water but not about whey-protein-folding in water that body-builders use with filtered shakers. Without filters, you get protein balls -- is ...
4
votes
1answer
127 views

Epilepsy explained by computational neuroscience

A few years ago, on my maths masters, I did a module in theoretical neuroscience. I was shown that the mathematical framework the course developed for neurons, with a small adjustment in the ...
10
votes
1answer
1k views

Is the eukaryotic nucleus composed of a single or double membrane?

I know that it is usually considered a double membrane like those surrounding mitochondria and chloroplasts, but I read a review that stated "according to topological details it is actually a single ...
3
votes
1answer
2k views

What factors are known to affect evolution?

My understanding is that the possible mechanisms of evolution are: Environmental changes Cultural/mating preferences Population Immigration Genetic Mutation Am I missing anything? I've heard that ...
2
votes
2answers
137 views

Gametes of two different species

I always wondered why gametes from two different species dont fuse together to form an offspring. eg a donkey (sperm) and a female dog (egg) I know this is not possible but I'm just curious.
1
vote
1answer
132 views

How to manufacture different sized micelles in nano -scale?

I am trying to answer q5: "How can you manufacture micelles in A) nanometerer -scale B) and in ten nanometer -scale?" My Thinking Observations and some thinking Oil in ...
2
votes
1answer
239 views

What happens to colloidal particles in a liquid medium? And how to stabilize it?

Definition Colloid is a dispresion of small particles of one material in another. Definition 2 (Wikipedia) A colloidal system consists of two separate phases: a ...
5
votes
2answers
95 views

Do somatic cells alter their own nucleotide sequence?

I seem to remember reading that embryonic cells will frequently replicate the section of their genome containing rDNA by splicing in duplicate genes. The cells use this to produce ribosomes at a rate ...
3
votes
1answer
97 views

How do susceptible organisms prevent parasites from overcoming resistance?

Bt corn is genetically modified to kill borers, but "regulations require farmers to plant conventional varieties as well, which is intended to stop the borers becoming resistant." -Source How do ...
5
votes
2answers
173 views

Are there other mechanisms for mutation besides imperfect DNA replication?

I was reading http://www.askamathematician.com/2012/05/q-is-quantum-randomness-ever-large-enough-to-be-noticed/ and saw: [...] the evolution of entire species can be changed by a single mistake ...
7
votes
2answers
1k views

Why animals can move and plants cannot in general?

To clarify, I think the answer should be able to explain: What are animals? What are plants? What's the difference between animals and plants (How do biologists differentiate them, if they ...
1
vote
1answer
311 views

What animals stop other members of their species from mating and why?

(In particular primates) I know chimps do. Powerful alpha males chimp would beat up omega males that they caught mating. I know gorillas do. Powerful alpha males gorillas would beat up omega males ...
1
vote
0answers
37 views

How many pandemic H1N1 2009 virus sequences were submitted by the Indian NIV as of May 10, 2010? [closed]

The handout I was following is maddening. It says; "Go to the NCBI home page and select 'All Resources (A-Z)' and choose GenBank. Follow the NCBI Flu Resource link to determine how many pandemic H1N1 ...
13
votes
2answers
208 views

What is the contribution of viruses to the evolution of mankind?

I'm interested in horizontal gene transfer in bacteria, viruses, and organisms such as Bdelloid Rotifers. I've just read in Carl Zimmer's 'A Planet of Viruses' the following passage: As a host ...
4
votes
1answer
213 views

Cause of short sightedness/ far sightedness

I recently had gone for an eye test. The doctor told that short sightedness/ far sightedness is caused due to shrinking or expanding of the eye. One thing i forgot o ask him was what causes that ...
3
votes
1answer
98 views

Cucumber on the eyes

In many spas and salons I have seen people place a cold cucumber on their eyes. I think this might be for coolness, but why a cucumber? And Is it actually for coolness or for something else (like ...
22
votes
1answer
11k views

How does laughing gas (N2O) work?

Laughing gas (N2O), well, makes people laugh. How does just a gas make us do that, there has to be some hormones at work... So, I wanted to know how this works? What is the mechanism?
1
vote
0answers
54 views

Are the intestinal flora substantially different within a diverticulum of the colon?

From the Wikipedia page for the vermiform appendix: This proposal is based on a new understanding of how the immune system supports the growth of beneficial intestinal bacteria, in combination ...
8
votes
1answer
1k views

Is there a maximum amount of antibodies your body can keep?

I am wondering if you were theoretically able to get vaccinations or antibodies for any and every diseases and/or illness, would there be a limit to how many you can get and keep in your body at one ...
6
votes
1answer
103 views

Bicoid regulation of hunchback

I'm learning about development via the example of Drosophila embryogenesis. I understand that bicoid regulates hunchback, among other genes. My question whether the regulation is direct or indirect? ...
7
votes
1answer
355 views

How Does Green Tea Increase Metabolism?

According to the article "Green Tea Supplementation Affects Body Weight, Lipids, and Lipid Peroxidation in Obese Subjects with Metabolic Syndrome", Green tea increases metabolism and fat loss: ...
2
votes
1answer
5k views

What are the differences between white and brown adipose tissue?

What are the differences between white and brown adipose tissue? Here are some that I have come across: ...
4
votes
1answer
181 views

intravenous (IV) in the tail vein of an anaesthetized mouse

I trained myself to do intravenous injection on live mice. However, on anaesthetized mice you don't see the flux of your product showing that your injection was successful. In the same way, on live ...
9
votes
2answers
307 views

How is human biological clock modelled in modern science?

Im an engineer by education and i program a lot, so the question sounds weird to people from other disciplines. Im trying to better understand the human biological clock. Yet i do not really know ...

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