8
votes
3answers
147 views

Which part of the brain needs to be shut down to lose conciousness?

Whether it is mechanical (trauma), chemical (anaesthesia) or electrical - which part of the brain is shut down to cause loss of consciousness?
1
vote
1answer
58 views

Adaptability in immune system

I read somewhere that recently some people are trying to use harmless bacteria that live symbiotically in humans to express some portions of antigens of the harmful ones. Some people have raised ...
6
votes
1answer
2k views

Why does the heart use lipids (and not glucose)?

Fetal hearts use glucose as their primary metabolic substrate. Adult hearts use free fatty acids, which are less efficient (require more $O_2$ to synthesize the same amount of ATP); however, during ...
3
votes
0answers
336 views

Virus titre and copy number of integration

If I need to preform a genome-wide high throughput screen using pooled shRNA library infection followed by deconvolution by deep sequencing, how would I determine the optimal infection rate at which ...
2
votes
0answers
70 views

Why is a nicotinamide-tryptophan combination used to treat affective episodes in a few older clinical trials?

At least one of the journal articles that reported on such clinical trials allured to the nicotinamide-tryptophan pathway that I assume must be related to the metabolism of tryptophan into serotonin ...
4
votes
1answer
171 views

Are the brains of any herbivorous animals capable of utilising ketone bodies as an energy source?

I ask this question because earlier today I heard from a lecturer at my university that a sheep's brain cannot utilise ketone bodies as an energy source and hence with insufficient glucose supply for ...
2
votes
1answer
614 views

Molecular Evolution: Mrbayes never stops?

When I use my own data to build Bayesian phylogenetic trees using the software Mrbayes, after many generations, it never reaches stopping status (namely, the average standard deviation of split ...
10
votes
5answers
300 views

Introductory biology text for an outsider

I'm a maths major and I have an interest in learning biology. I know very, very little; I know how babies are made and that's about it. Could anyone recommend a stimulating text to read for it's own ...
1
vote
1answer
273 views

L1 - L5 layers of the brain

I have read in some papers about the layers L1-L5 of the brain (e.g. in this paper). I could not find a definition of these layers. I have found information about the layers V1-V5 in the visual ...
8
votes
2answers
1k views

Free software for measuring parts of an image? [closed]

Let's say I have a picture of an insect wing and a ruler on the same image. Is there any computer program that I can use to calibrate with the ruler and then get a measurement on the wing length? ...
2
votes
1answer
185 views

Genetics problem-Height of a plant

An inbred strain of plants has a mean height of 24cm. A second strain of the same species also has a mean height of 24cm. When these plants are crossed the F1 are also 24cm in height.However, when the ...
2
votes
1answer
73 views

How correlated are proximally related CpG sites in human DNA?

Cytosine residues in DNA that can be methylated (i.e. CpG sites) are likely to be in the same methylation state if they are geographically (proximally) close together. I can only find one paper that ...
2
votes
2answers
54 views

What is the role of hippo signalling in oral squamous cells

What role do hippo signalling have on squamous cells in oral health & diseases
2
votes
1answer
63 views

Extract bacteria from compost?

I'm working on a project where I need to find certain cellulolytic bacteria. I was looking at this list : ...
1
vote
0answers
22 views

Do Total Gastrectomies leave individuals more open to infections from eating unsanitary food?

I ask this because the stomach plays a role in sterilising food and hence without one it follows that perhaps one would be more prone to getting intestinal infections.
1
vote
1answer
53 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
205 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
333 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
91 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
77 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
325 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
147 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
179 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
42 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
95 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
72 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
55 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
902 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
82 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
101 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
73 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
94 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
135 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
118 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
114 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
68 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
104 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
816 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
92 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
752 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
246 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
1k 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
693 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
62 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
687 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
118 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 ...

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