1
vote
1answer
55 views

Does sympathetic nervous system acts bilaterally for pupil dilation or other two sided organs?

The question might seem weird. Does sympathetic nervous system acts 'bilaterally' meaning if you shout to a person's left ear a loud noise (e.g. by headphones), will it activate sympathetic system ...
1
vote
0answers
38 views

Root hair formation in Arabidopsis

In arabidopsis, 2 cell types arise in the root epidermis : root hair cells and hairless epidermal cells. The immature epidermal cells that are in contact with 2 underlying cells of root cortex ...
2
votes
3answers
218 views

Mechanical cause of loss of consciousness

Consciousness is an electrical and chemical interaction in the brain, caused by neurons firing and chemical interactions. How does a mechanical "force" cause this to stop working? i.e. How does a ...
3
votes
1answer
373 views

Are there any 6 limbed reptile fossils?

Were any 6 armed "tetrapod" fossils ever found? I've seen some lobe finned fish with two sets of shoulders in an evolutionary bio book... I'm curious because I'd like 4 limbed and 2 winged dragons to ...
3
votes
1answer
101 views

How do muscle relaxants work?

Do they act directly on the muscle and actually relax muscle tissue and ease spasms, or do they just prevent your brain from receiving signals that inform you of tight muscles? In the latter case, ...
3
votes
1answer
82 views

What's the mechanism for pain-induced swoon?

Is it true that people will pass out when subject to pain too much to bear, or there's no such threshold? What's the reason for passing out under acute pain, even if no physical injuries occur (e.g, ...
6
votes
1answer
351 views

evolutionary reason behind sharing the same path for food and air?

What is the evolutionary reason behind sharing the same path for food and air? For example, we have a nose and lungs, yet they are linked by the pharynx, which is shared with the mouth and ...
1
vote
1answer
163 views

how to clone a gene fragment in two direction as sense and antisense in vector

I have a sequence ATG GGG CCC TTT AAA TAA and want to use it as antisense RNA in my vector. How should I clone it? I am confused with the direction of my clone. I looking for the direction and ...
3
votes
1answer
191 views

Are human feces and urine merely a subset of the food and liquid we eat and drink?

In other words, does the body actually ADD ANYTHING TO urine or feces? As the food and drink makes its way from our mouth to our toilets, does the body add anything to it along the way? Or, is the ...
0
votes
1answer
71 views

How does the matter that makes up the fat of your fat cells ultimately leave your body--following weight loss?

I'd like to get some clarification on specifically how the matter from the fat reserves of the Adipocyte physically leaves the body. In other words, if you were to somehow follow every atom in the ...
1
vote
1answer
44 views

Human defenses to toxoplasmosis

Toxoplasmosis modifies the rat's brain to make them love (and be eaten by) cats. It also infects ~30% of humans, and modifies traits in several bad ways (i.e. schizophrenia and increased reaction ...
1
vote
2answers
107 views

How precise is EEG?

Imagine we want to read impulses within single neurons in the brain. Can we do that now for a single region within the brain? If not, what is the smallest region that can be monitored for an activity ...
2
votes
0answers
73 views

Where are the gastralia (stomach ribs) attached?

Crocodiles and some dinosaurs have a second set of ribs between the sternum and pelvis called gastralia. Where are the gastralia attached to the rest of the skeleton?
4
votes
1answer
58 views

When do kinetochores attach?

I am really confused as to when kinetochores are attached to centromeres. Are they attached soon after replication or after condensation ?
1
vote
1answer
977 views

Does mitosis include cytokinesis?

I found that some books include cytokinesis within mitosis, but some other books I have referred to include only the dividing of the nucleus as mitosis and do not include cytokinesis. Can anyone help ...
1
vote
1answer
85 views

What stops the coagulation process?

Whenever there are minor/major injury to blood vessels, the platelets, fibrin, thrombin, etc. are recruited. They then seal the wound and block bleeding. What tells them that their job is done?
0
votes
2answers
103 views

Why can't cell division happen the other way around?

Mitosis in eukaryotes happen in this order: DNA replicates and then the cell divides. Why doesn't it happen in reverse order (i.e., cell divides and then replicates the DNA)? I am talking about ...
1
vote
1answer
77 views

Are there any bacteria that can receive ultrasound signals?

I'm looking for an example of bacteria that could receive ultrasound (at any ultrasound frequency) signal and possibly perform some (re)action afterwards.
1
vote
1answer
104 views

Complementarity of cDNA

Strictly speaking, what is the definition of cDNA? This confuses me, since usually it is said to refer to DNA that is complementary to mRNA. Is this correct? Is it restricted to mature mRNA? I ...
1
vote
1answer
144 views

Why are Taurine and Arginine essential components of the feline diet?

Taurine and arginine play a key role in the feline diet but I am unaware as to where exactly they fit in.
3
votes
1answer
2k views

Why is FADH2 made instead of NADH in one of the reaction of Krebs cycle?

FADH2 is made in conversion of Succinate to Fumarate. Why is this so ? Why not NADH ?
1
vote
0answers
127 views

Why can't sodium butyrate be delivered orally in humans and other mammals?

I think I know why -- bioavailability problems but since I have no firm evidence to support this theory I thought I would ask the biology stackexchange community for their input. I'd like some firm ...
3
votes
1answer
115 views

Other than Acetylcarnitine what other orally-bioavailable Acetyl donors exist to assist in the conversion of CoA to acetyl-CoA?

I asked a question on bio stackexchange a few days from which I was hoping to be able to arrive at an answer for this question myself but I have had no such luck so now I am going to just ask ...
0
votes
1answer
69 views

Is forced cell growth related to apoptosis?

Could an instance of forced cellular growth cause some cells to have their self-destruct mechanisms to malfunction or 'turn off'thus preventing apoptosis?
0
votes
1answer
115 views

How does the enzyme Dicer function in the RISC complex?

I know that the RISC (RNA-induced silencing complex) is one of the primary complexes involved in gene regulation through RNAi. What I want to know is, what role exactly does Dicer play in this ...
2
votes
3answers
857 views

Genetics: pedigree following a rare trait autosomal recessive

I have two questions pertaining to this pedigree I believe it to be an autosomal recessive trait. The probability that individuals IV-1 and IV-2 would give rise to an affected individual would ...
7
votes
1answer
107 views

How significant is RNA degradation with removal of cap/polyA's in eukaryotes, or UTR's in prokaryotes?

Question is rather self-explanatory, but segmented into two parts. I'm attempting to make use of a repression system that employs cleaving RNA at specific areas with ribozymes with the intent of ...
3
votes
2answers
793 views

Can any one reaction in a cell be at equilibrium?

I know that metabolism as a whole can never be at equilibrium (otherwise the cell is dead !) but I wonder whether a few reactions in the cell could be at chemical equilibrium at a given point of ...
2
votes
2answers
262 views

Why don't plants get sunburned?

I just saw a video about the biology between sunburn, UVA and UVB and the different things we know about sunburn in humans. ( http://www.youtube.com/watch?v=ZSJITdsTze0 ) I wonder what keeps plants ...
1
vote
1answer
2k views

Why in some cells is GTP made in citric acid cycle and in some ATP?

In many animals GTP is produced in citric acid cycle. While in plants,bacteria and some animals ATP is produced. Why is this so ? What is the advantage ?
3
votes
1answer
768 views

Why do brain cells use shuttles that pass electrons from NADH to FAD?

Brain cells are cells require one of the highest amount of energy of any cell of body. So why do they use a shuttle which will transfer electrons from NADH produced in glycolysis to FAD(and there by ...
1
vote
1answer
50 views

Where can I find pdb files for macromolecules like receptors?

I have tried going to the RCSB website and quite frankly it was useless since when I looked up receptors like say the metabotropic glutamate receptor 2 (mGluR2) I got no helpful results.
2
votes
1answer
63 views

How do you differentiate between SR protein and SR-like protein?

What are the criteria that the researchers use to choose whether a protein is an SR protein or and SR-like protein?
2
votes
1answer
720 views

Is there any advantage of having a mitochondria for aerobic respiration?

If we consider the pathway of breakdown of glucose which includes glycolysis, the citric acid cycle and the electron transport chain, all these processes takes place in some prokaryotes and ...
4
votes
4answers
119 views

How to calculate extent of Sequence similarity [closed]

I had a problem that I was wondering if it could be solved by one of the techniques/algorithms used in bioinformatics to give the extent of similarity. I have a Problem Statement: we have a sensor ...
2
votes
1answer
64 views

observed luminescence in a piece of plaice

A plaice fish bought for human feed has been cleaned and cooked. Some parts of the raw body have been left out of the fridge at about 22°C for about 15 hours. During the following night a ...
4
votes
1answer
826 views

How to secrete a recombinant protein from E. coli?

What are some secretory pathways that can be used to secrete a recombinant bacterial enzyme from E. coli? I have a recombinant protein (29kDa) that I will express in E. coli BL21 cells. For now I ...
12
votes
4answers
5k views

Why we have no enzyme to digest cellulose?

As we know, cellulose is the most abundant polysaccharide in nature. Why don't we have any enzyme to digest cellulose?
3
votes
3answers
581 views

How to calculate virus titre from qPCR

I harvested some lentivirus from 293T cells and want to titre the result. I infected 293T cells on a well plate with 400,000 cells per well which I infected with virus stock, and 1 in 10, 100 and 1000 ...
2
votes
3answers
77 views

Where can I find an at least Semi-Comprehensive list of what biochemical reactions Acetyl-CoA participates in?

Acetyl-CoA has a number of biochemical roles in the body and I'm curious as to whether anybody knows where I can find at least a semi-comprehensive list (i.e. comprising all the major roles in the ...
0
votes
1answer
428 views

Strongest muscle of Human Body

Which is the strongest muscle of human body ? Confusion b/w Masseter muscle (Muscle of Jaw) and Tongue and Muscle of Heart and Muscle of Uterus.
4
votes
2answers
126 views

How long can C. Tetani survive in soil?

Clostridium tetani (C. tetani) is a bacterium commonly found in soil and is excreted in the faeces of many animals (both mammals and birds) and serves, by means of the exotoxin, tetanospasmin, causes ...
1
vote
2answers
418 views

Amount of Heterozygosity

How many loci in the human genome are heterozygous? How about other species? EDIT: I was wondering, considering for example the whole world population, how many of the human genes actually have two ...
1
vote
1answer
77 views

Why to choose a grammar from a lot of grammars that can describe structure of proteins? [closed]

Why do we choose a grammar from a lot of grammars that can describe structure of proteins? Usually, there are a lot of (maybe infinite) grammars that can describe one language. Why do we choose a ...
2
votes
3answers
518 views

How is the mRNA transported out of the endoplasmic reticulum?

In eukaryotes the nuclear envelope is continuous with the ER, so what helps it out of that?
2
votes
1answer
71 views

Domains in cell membrane

How is movement of proteins and lipids between different domains of cell membrane prevented? Why is the noncytosolic layer not able to do lateral movements between domains but cytosolic layer is able ...
1
vote
1answer
715 views

What is 'calcium conductance'?

What is the meaning of calcium conductance in ion channels. I encountered this in the following text: It was established that the µ and δ opioid receptors open potassium channels, which results ...
-1
votes
1answer
309 views

I think evolution has goal [closed]

Richard Dawkins says evolution doesn't have any goal. But I think evolution has one. At the end evolution creates intelligent being. If we find another earth like planet evolution sould have the same ...
0
votes
1answer
37 views

What are some possible causes that might explain why the global temperature has remained relatively constant in the last decade? [closed]

First - I do not know if this is the best site to pose this question. However, stack exchange does not appear to have an ecology sub-site. That said, this appears to be the most appropriate place ...
4
votes
2answers
483 views

Could be an union/synergy between Math, Computer Science and Marine Biology?

I'm studing for my bachelor's degree in Natural Science and I have to chose the path for my future life. I have to chose the right kind of graduate studies. Since I love computer science, maths and ...

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