1
vote
1answer
88 views

Electron transport in granal stacks

See paper for distribution of PS-I and PS-II within grana As explained in the above paper, the PS-I complex is primarily located within non-appressed thylakoid region and stroma lamella, while PS-II ...
5
votes
1answer
82 views

Photosynthesis regulation

I read about the regulation of Calvin cycle by thioredoxin which activates key enzymes essentially by converting disulphide linkages on inactive enzymes into sulfhydryls. Another regulatory mechanism ...
2
votes
1answer
361 views

What is the relationship between UV wavelength and penetration depth into human skin?

Some background - Some recent research has strongly suggested that UVA penetration into the skin is far more dangerous than UVB, a very good example is this paper by Agar et al. (2004). My query is, ...
2
votes
2answers
87 views

E. coli, risk of infection?

There has been a warning about E. coli contaminated water in South Florida. Now I'm wondering are there empirical data or historic cases which show a correlation between E.coli levels in tap water and ...
2
votes
1answer
49 views

Deep diving in mammals

Mammals like seals often dive and can remain under water for more than 70 minutes. How do seals know when is it the time to come up?
0
votes
0answers
100 views

Understanding SIR models in epidemiology

We are doing research on a SIR model of an epidemic. For one of the subsections, we are talking about saturation content rate of a human. We would like to know if anyone has an understanding of ...
2
votes
2answers
4k views

Can the excessive consumption of mineral water lead to kidney stones or other health issues?

I heard that drinking too much mineral (bottled) water could lead to problems such as kidney stones because of the high amount of minerals in it. Is it true? If so, what is considered to be excessive? ...
1
vote
2answers
111 views

Which texts are good for beginners to understand evolution on the genetic scope?

Are there good texts to study the evolution, how it works, and how mutations and changes lead to evolution of the organism ? And how does the information increase through the long time using ...
4
votes
1answer
150 views

How is consciousness linked to the brain?

Could the brain be working without consciousness? Does the brain interact with consciousness? Alternately, is it that consciousness can't really control the brain, and you only have the impression ...
1
vote
2answers
56 views

Are there beneficial genetic mutations identified by consumer DNA genotyping?

I'm looking at services like 23andme, and see that they identify a wide variety of genetic-based risks, like predisposition to diseases, hair loss, cancer, etc. Are there a more "positive" DNA ...
1
vote
1answer
398 views

How do viroids propagate to other hosts?

As viroids are simply non-encapsidated non-coding RNA molecules, it is difficult to imagine a mechanism for their continual infection, other than horizontal transfer which doesn't seem to be the case. ...
1
vote
1answer
61 views

Breaking of fats

There is a question I encountered. Why is fat harder to digest ? A) It has ester bonds. B) It is not easily soluble in water. Which is the most appropriate answer?
6
votes
3answers
146 views

Why are males more likely than females to have autism spectrum disorder?

The male to female ratio in autism spectrum disorder is around 4:1. However it seems ASD is not a simple X-linked disorder. Then how is it possible males are more susceptible than females, if the ...
1
vote
1answer
247 views

What is a good Microbiology atlas for Bacteriology as online version?

I am looking for a online atlas for Bacteriology, the cost does not matter. I have been searching SpringerLink, and Amazon but no good online version found. What is a good atlas for Bacteriology as a ...
0
votes
2answers
87 views

Sewall Wright for dunces

[This is one more post in my growing "X for dummies/idiots/morons/etc." series.] I've been enjoying Provine's The origins of theoretical population genetics for the last couple of days, but I must ...
1
vote
3answers
203 views

What flying insect is this?

Found in Russia. Approx. 7 cm.
1
vote
0answers
572 views

Low RNA yield, low 260/230 ratio

I extracted total RNA from animal tissue using the Qiagen RNeasy kit, however my RNA yield was extremely low and the 260/230 ratio was around 0.3. This is the protocol I followed: The animal ...
3
votes
3answers
731 views

Polymorphism in cnidarians?

To me, the phenomenon of polymorphism in cnidarians is particularly troubling. I gather that it essentially refers to existence of various different forms or kinds of individuals, i.e. zooids and ...
2
votes
2answers
292 views

Transcription factor binding site located in intron

I have noticed that some TF binding sites are located in the introns of the genes. I am puzzled about whether the TF only binds to DNA in the initiation stage of transcription and will detach during ...
0
votes
1answer
627 views

Structure of adenoids

I am not sure this question belongs in biology, but I can't find a more suitable stack exchange site, feel free to delete it if this doesn't fit here. Also, this question is going to be slightly ...
1
vote
0answers
58 views

Is there a biological process which causes organs to atrophy in response to enivronmental stressors?

I am aware of what happens when the body experiences starvation and breaksdown the muscles in the body for protein sources and the other processes that happen in such a scenario. However, i wondered ...
5
votes
1answer
123 views

Is there a DNA test to identify dog mixes?

We adopted a dog at the age of two. Our vet said it was a mix of an Australian Shepherd and Border Collie, which we've told everyone. Based on markings, I think it's likely. I am wondering, however, ...
3
votes
1answer
649 views

How does a virus take control over the host cell?

When the virus integrates its DNA with the hosts and enters the lytic pathway, do the viral proteins that produced destroy the cells DNA? Do they deactivate it? Also does the cell function in the same ...
1
vote
1answer
51 views

Do Acyl Carrier Proteins and Conenzyme A have similar reactivity?

In terms of the reactions they undergo are they roughly equivalent groups?
1
vote
1answer
811 views

What are the differences between G+ and G- bacteria?

The distinction between Gram-positive and Gram-negative bacteria is based upon the Gram staining method, that reflects the bacterial wall physical properties. However, this classification involves ...
-1
votes
2answers
115 views

Blood circulation and blood pressure in different tissues [closed]

The volume of blood coursing the blood circulation is approximately five litres. A typical vein will stretch about eight times as much as corresponding artery. Because veins have high capacitance, ...
3
votes
3answers
155 views

How is antibody production stopped?

Once clonal selection is done, B cells would start dividing and producing antibodies. So, after an antigen is eliminated, what stops the division of B cells and antibody production?
1
vote
0answers
31 views

Randomized experimental design in genetic experimentation.

I am struggling to find out if randomization is used in traditional genetic breeding experimentation with model organisms, especially in lab contexts? And why this should be so? This is part of a ...
4
votes
1answer
74 views

Are there any bacteria, in our environment, able to break down nitrate under aerobic conditions?

Given a fix volume of water saturated with dissolved oxygen through aeration. Suppose that ammonium, Nitrosomonas, and Nitrobacter are always available in the water. We know that some of the ammonium ...
2
votes
1answer
37 views

Are CoA and CoAS the same thing in a compound?

Is CoA-S-R the same as CoA-R, and is CH3C(=O)CoA the same as CH3C(=O)SCoA? Eg. Above is the compound on the right just coenzyme A or is it actually another compound and not just notation?
0
votes
3answers
76 views

What are the allowed evolution operators (on protein encoding sequences)?

What are the evolution operators, meaning allowed actions on the DNA sequence that encodes a protein. I assume all evolution of genes is a result of duplication errors. So an answer could look ...
1
vote
1answer
116 views

Do nerve cells cause action potential in cardiac muscle?

I think the answer is no, but I am not 100% sure. If it was yes, then the dendrite of the nerve cell should each time receive a stimulus causing Na+ channels to open, when the contraction happen. ...
2
votes
1answer
106 views

Can songbirds mimic car alarm sounds?

A silly question. A few days ago I observed a very vocal bird with impressive vocal variety. It was rapidly switching from one tune to the next. After sometime I realized that the bird might be ...
2
votes
2answers
169 views

Change in conditions of an ecosystem lead to change in organisms

Let's think about the slash and burn method and its effects on the ecosystem. Cutting down trees that rise all the way up to the canopy would expose the plants at ground level to more light, so would ...
1
vote
1answer
94 views

Which hormones/factors affect Calcium absorption in the small intestine and its regulation?

I think the question is very broad and cannot find precise mechanisms. I am not sure about the precise mechanisms of the regulation. I think they are at least Vitamin D, diffusion and specific ...
2
votes
1answer
65 views

Autophagy in eukaryotic cells

What is autophagy? How and under which circumstances is it used by the cell? I believe The reason for autophagy is some kind of recycling, am I right? But why does it occur in infections?
6
votes
1answer
122 views

Same 185th million grandfather?

I was watching a lecture by Richard Dawkins earlier today and he mentioned that “Your 185th million grandfather was a fish.” I started wondering about the following question, Is it true that my 185th ...
1
vote
1answer
37 views

How can I learn about how cloning works in nature (twins)?

I would like to learn about how the process of cloning works in nature - how are twins "created" after fertilization what genetic changes can occur in each of the twins. Where should I start? What ...
4
votes
1answer
94 views

Is it possible to condition the body to reduce bruising?

I do combat sports, and in these sports there are a lot of hits that can cause bruising. I've found that, over time, physical conditioning can reduce and/or eliminate the bruising to the point where ...
4
votes
1answer
134 views

Plasma cells and memory cells

What decides whether an activated B cell will get converted to plasma cell or memory B cell? Is it necessary that out of a mitotic division one will convert to memory B cell and the other to plasma ...
5
votes
2answers
221 views

Do we have enough diversity of antibodies to overcome almost any antigen?

I always wonder about the capability of diversity of our antibodies. Do we have enough antibodies to fit to every kind of molecule? Wont't it be easier if our antibodies are like clay and can be ...
2
votes
1answer
273 views

Why do humans bury their dead?

As far as we know Ape Men or the Neanderthal Man was the first to bury its dead. My question is why. I don't think they practiced religion or believed in spirits or faith or stuff like that. ...
5
votes
1answer
53 views

What regulates these two methods of splicing?

Alternative splicing can shuffle the exon order and select from the exon sequence of a single gene site to provide a combinatorial selection of possible transcription products from the one gene. Can ...
2
votes
1answer
317 views

Comparing BLAST and the Smith-Waterman algorithm

I've been asked: how does BLAST improve dynamic programming accuracy? I do know that BLAST is based on heuristic approach that approximates the Smith-Waterman algorithm and that the Smith-Waterman is ...
1
vote
0answers
29 views

Avian Diseases : How to Disinfect

How can I sanitize a bird's carcass so that no diseases are present after disinfection? I was thinking $\gamma$-ray bombardment since ozonation would only surface disinfect.
7
votes
1answer
54 views

Intracellular lipid transport

I know that lipids are carried around the body in the blood either as micelles or by lipid-binding proteins which allow them to be solved. Lipids can't always be integrated in a membrane though, the ...
2
votes
2answers
119 views

Prenatal Marketing

This is for a short story idea. Is it possible to modify the DNA of a child to make their metabolism more susceptible (physical response, addiction, etc) to a certain type of chemical i.e. a chemical ...
2
votes
0answers
55 views

Movement of stem cells from mother to fetus

Recent results from J Lee Nelson and colleagues (Sci Am. 2008 Feb;298(2):64-71; available as full text through Google) show that cells from the mother were found in a person aged 46. Logically, these ...
2
votes
1answer
71 views

How to bind antibodies to study their properties?

I want to experimentally look at the behavior of antibodies. To do so, I need to be able to bind these antibodies to a substrate. Does anybody know of a good substrate to use that antibodies bind to? ...
3
votes
2answers
442 views

Just how light-sensitive is ethidium bromide?

One lab I was in was paranoid about keeping it in a foil-wrapped conical tube; my current lab leaves it out on the bench (and it works fine for staining gels). It's the same company/concentration in ...

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