5
votes
2answers
52 views

tools to reconstruct the transcriptional regulatory circuits?

What are commonly used tools to reconstruct the transcriptional regulatory circuits that govern diverse cellular responses and what input data sets do they accept?
17
votes
2answers
294 views

What are the major evolutionary pressures for Bioluminescence?

What are the major evolutionary pressures for Bioluminescence?
4
votes
1answer
214 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?
5
votes
1answer
93 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? ...
1
vote
1answer
289 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 ...
4
votes
0answers
36 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 Takigufu rubripes compared to zebrafish? Ultimately, I would like ...
18
votes
4answers
2k views

Do trees really get a large share of their mass from the carbon in the air?

I remember hearing that trees and other plants actually obtain a large amount of their mass from the carbon floating in the air, not the ground beneath them. Does the makeup of air actually contain ...
0
votes
1answer
115 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 ...
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 ...
7
votes
1answer
61 views

Which factors besides the thermodynamic stability are important for the hairpin in intrinsic transcription termination?

Intrinsic termination (rho-independent) relies on a stable hairpin with a subsequent uridine repeat. The common explanation on how these sequences cause the termination of the transcription are based ...
0
votes
1answer
181 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 ...
2
votes
2answers
175 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 ...
4
votes
1answer
1k 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 ...
6
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 ...
6
votes
1answer
601 views

What happens to a human body once a sugary snack is consumed?

I'm looking to understand the effects of sugary snacks and/or drinks on a human body. I'm particularly interested in the timing of the ingestion versus various hormonal levels that may be circadian in ...
9
votes
2answers
781 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 ...
3
votes
1answer
294 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?
7
votes
1answer
254 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 ...
12
votes
1answer
161 views

Have any mutations or genetic loci been associated with exceptional longevity in humans?

Individuals that avoid age-related diseases into later life are known as 'exceptional survivors', and have increased longevity compared to their 'controls' (those that were born at a similar time, yet ...
6
votes
3answers
242 views

Weighing 2 vertical halves of the human body

I had this thought while bathing: Assume a perfectly developed physical human body and anatomy in terms of size, dimensions and proportions. In theory, if I cut the body vertically into two exact ...
1
vote
0answers
151 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 ...
1
vote
1answer
126 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
2answers
130 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.
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 ...
2
votes
1answer
232 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
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 ...
3
votes
1answer
95 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
1answer
169 views

Are quaternary protein monomers unique to a particular protein complex?

I know that quaternary protein structures are formed exclusively via non-covalent bonds. My biochemistry professor discussed a viral capsid that is essentially one quaternary structure with 240 ...
5
votes
2answers
162 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 ...
9
votes
1answer
496 views

How does laser surgery correct accommodation problems?

When someone undergoes laser surgery to improve eyesight, how does it correct accommodation problems? Why does it not help presbyopia?
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 ...
8
votes
1answer
900 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 ...
1
vote
2answers
2k views

Restriction Mapping of Plasmid Assignment

pUWL22 is a circular, double stranded, 10.5 kb plasmid. It contains a gene encoding an enzyme that confers ampicillin resistance in the host bacterium. Cloning into the kpn I and Sst I sites ...
4
votes
1answer
172 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 ...
13
votes
2answers
12k views

Possible? When a pregnant woman suffers an organ damage, fetus would send stem cells to the damage organ to help repair it?

I am quite sure that there is this blood-placental barrier between the mother and the baby so that nothing (except a type of antibody) can pass through it. But I remember reading somewhere that when ...
4
votes
2answers
674 views

Why is proteinase K digestion performed at 50 °C?

Many DNA isolation protocols use a Proteinase K digestion to remove proteins. This is often performed at 50 °C. Why is this?
1
vote
1answer
917 views

What are the positive and negative effects of insulin on cognitive function?

A UCLA study seems to imply that insulin interferes with cognitive function. The DHA-deprived rats also developed signs of resistance to insulin, a hormone that controls blood sugar and ...
3
votes
2answers
107 views

What risk to DNA does long-term exposure to low-dose radiation pose?

A new study from MIT scientists suggests that long-term exposure to low-radiation poses no risk of DNA damage for mice (it is also important to note that mice are unusually susceptible to cancer). So ...
6
votes
1answer
69 views

Question: Annotation search in scientific literature

In a scientific paper I have been studying ("Predicting Novel Human Gene Ontology Annotations Using Semantic Analys" S.Draghici et al., 2010), I have read that authors checked the accuracy of their ...
7
votes
3answers
371 views

Can protein structure be determined by X-Ray Diffraction in a single image?

I'm reading about the use of x-ray crystallography to determine protein structure. According to my book, data is collected at 30-360 angles (dependent on the symmetry of the protein). An illustration ...
9
votes
3answers
184 views

Does GFAJ-1 use Adenosine triarsenate as its energy currency?

Regarding the bacteria found in Mono Lake, CA that scientists believe uses or can use arsenic in its DNA backbone where life as we know it uses phosphorus (according to their experiments depriving the ...
5
votes
1answer
51 views

Why are some plants frost tender?

Why do some plants have the ability to stand frost, while others can't? Does it have to do with the size of the water vacuoles in the plant cells?
18
votes
2answers
3k views

What actually happens when my leg 'falls asleep'?

Most people have experienced the temporary loss of feeling and tingling in their leg resulting from sitting in an abnormal position for a short while. Usually you get a loss of feeling in your leg ...
7
votes
1answer
860 views

How does one calculate the resolution of a crystal structure?

Considering that I have a diffraction pattern of a crystal, how would I calculate the resolution of a structure in Angstroms? How does that value differ from the information that I would get from the ...
13
votes
1answer
434 views

How fast will cells lyse under hypotonic conditions?

Routinely, lysis of cells with hypotonic solutions is carried out along with some physical (douncing) or enzymatic (lysozyme) method to break open the cells. If one were not to do any of these and ...
9
votes
1answer
917 views

Will the “frog in boiling water not jumping out” work on warm blooded animals

There is the famous saying about a frog that is put in water that are slowly boiling will not jump out until it's too late. I realize it happens because of the frog's cold blood that adjusts to the ...
19
votes
1answer
244 views

Evolutionary origin and exogenous cues of ~28 day infradian rhythm?

The most obvious example of an approximately monthly biological cycle is the human menstrual cycle. My questions are the following: Is it known when and where this cycle or one like it arose? What ...
6
votes
1answer
181 views

Decreasing the alcohol proof and faster in hangover, why?

My russian friend says that the USSR agents used/use the trick that they offered the victim first vodka and then last wine. I have noted that this puts you faster to hangover: decreasing the alcohol ...

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