7
votes
2answers
169 views

The Assumption of Weak Selection?

I was reading this question and I failed to fully understand the introductory part of it. The OP (@Artem Kaznatcheev) says: Most analytic models like to assume weak selection because it allows ...
2
votes
0answers
89 views

Predicting host-pathogen gene interaction networks

Background What we have are: ~20 genome sequences for a host species that come with gene annotations Several sequenced genomes for parasite/pathogens of these hosts Question What are the ...
1
vote
0answers
58 views

DNA fingerprinting

I would like to make my own DNA fingerprint - just for fun to have my "autoportrait":). I was looking around a bit and all the commercial kits you can have are very expensive. Can you suggest me a ...
3
votes
2answers
84 views

Mass Spectrometry Terminology

I began reading this paper (http://www.biomedcentral.com/1471-2105/14/56) and had a few questions about mass spectrometry terminology that I couldn't find answers to elsewhere. Consider the following ...
5
votes
3answers
389 views

Aerobic vs anaerobic respiration comparison

The following graphs compare glucose decomposition in yeasts (in anaerobic vs aerobic conditions respectively) My question is, why doesn't the first one look like a straight line as the second one ...
3
votes
2answers
181 views

Lactate and Diabetes

Why are lactate level high in diabetes? For example, Diabetes type II have resistance to insulin, and if they do it, their gluconeogenese should be working at high levels and, because of that, uptake ...
1
vote
2answers
172 views

Evolutionary history: did any organs start out as autonomous organisms?

I've read that the cell nucleus was once an autonomous organism that was "enslaved" by the larger cell at the time of the Eukaryotic Revolution. Are there any organs in the human body that we know of ...
1
vote
1answer
193 views

Definition of “Regime of selection”

How would you define Regime of selection (or Selection regime)? In addition to a accurate definition, a developped example ...
-1
votes
1answer
218 views

Gene transfer between Gram positive and Gram negative bacteria?

How does transfer of genetic material occur between Gram positive and Gram negative bacteria?
1
vote
1answer
95 views

Why does sulfonamid not inhibit the growth of Rickettsia?

Sulfonamid is an antimicrobial agent, why has it no effect on the growth of Rickettsia?
4
votes
2answers
74 views

Do swarms show intelligence?

Can you think of collective and swarm behaviors as "intelligence"? Would such a concept apply to a) ant colonies and b) fish swarms?
4
votes
2answers
127 views

What is the smallest oligocelluar organism?

What is the smallest oligocelluar organism? How many cells does it have? EDIT The question is motivated by this comment@Philosophy.SE EDIT as recommended in comments I'm looking for an example of ...
1
vote
1answer
84 views

Are these bat social calls?

I'm currently researching bat social calls (not echolocation calls) and have been given a series of samples (in .wav format) and wanted to know, if what I can hear is actually the social calls. Below ...
4
votes
2answers
2k views

On which strand does the promoter sit?

My book keeps giving different indicators as to whether the promoters are on the coding or template strand. It says the -35 region in prokaryotes must be on the coding strand. It also mentions, that ...
0
votes
1answer
206 views

How can synonymous mutations lead to cancerous or tumorous phenotypes?

After analyzing DNA sequences of an oncogene from many human cancer patients, you found that synonymous substitutions occur in a specific codon of this oncogene. Assuming that these synonymous ...
2
votes
1answer
192 views

Why are haploid cancer cells not killed by immune system?

I have seen haploid cancer cells (I think it was leukemia cells) in a lab. Sperms and eggs are haploid but are not destroyed by the body because they are protected by other cells surrounding them. ...
3
votes
1answer
142 views

Drosophila melanogaster eclosion

Is there any published data which shows the number of Drosophila melanogaster fruit flies eclosing (hatching out of the pupae) against time since egg oviposition? I'm thinking there should be ...
3
votes
1answer
567 views

Action potential and sodium channels

In this video on electro tonic potential, the tutor says that when the potassium channels open the potential drops from +40mV to -80mV, where the sodium channels have already closed at +40mV. Now in ...
4
votes
1answer
894 views

Causes of monozygotic twins

Twins could be monzygotic i.e. identical twins and dizygotic i.e. non-identical twins.Well, monozygotic twins occur when a single egg is fertilized to form a zygote which later divide into separate ...
3
votes
1answer
1k views

Is the complement system a part of innate or adaptive immunity

I've been reading about the complement system, as part of the human immune system. The complement system is introduced as part of the article on innate immunity on Wikipedia. This classification makes ...
6
votes
1answer
120 views

Disproportion in cranial nerve innervation?

The cranial nerve innervation is highly disproportionate, as far as humans are concerned. I am not sure of the advantage of being innervated by cranial nerve versus being innervated by a normal ...
0
votes
1answer
85 views

Stomach sagittal section

Can anyone please tell me where is exactly the stomach in this image? This is a sagittal section from the University of Michigan Visible Human Browsers. Thank you.
1
vote
0answers
68 views

What are current abiogenesis hypotheses for first food source?

What is the very first abiogenetic piece of reproducing life (small piece of RNA + ribosome that randomly occurred?) hypothesized to have used as an energy source? I'd be interested in sources to what ...
1
vote
1answer
2k views

Why is prothrombin time test not used for heparin

Prothrombin time test is used for the monitoring of warfarin but not heparin. Why is this used for warfarin monitoring and why is it not used for heparin monitoring?
2
votes
1answer
52 views

Epistasis when interacting loci are codons within a single gene

There is epistasis when the effect on the phenotype of one gene is influenced by one or more other genes (called modifiers). Is there a similar concept when the effect on the phenotype of one site ...
3
votes
1answer
95 views

Activation Of Embryonic Genome

Embryonic gene activation is a process by which the embryo begins to transcribe its newly formed genome.As the embryonic gene activation occurs during early stages the paternal genome may not have any ...
1
vote
1answer
81 views

Effects of smoking tobacco compared to inhaling other smoke

How much less dangerous is breathing smoke from burning wood and coal compare to smoking tobacco? Edit: Sorry. I should have made the question clearer. If this were an experiment, it would be set ...
4
votes
1answer
59 views

Do local field potentials (LFP) create waves on the surfaces of nerve cells?

Are waves created by the LFP on the surfaces of neurons cell bodies? Since the cells have a resting potential, do these waves create harmonic oscillation of the membranes at particular frequencies? ...
1
vote
1answer
49 views

Do all animals exhibit comparable reflex velocity?

First, my exposure to biology is high-school. Should the answer to the question be obvious - please take a moment to laugh, and then point me in the right direction. A quick google search (or perhaps ...
0
votes
3answers
87 views

What is the datatype of dna sample?

What is the type of data you get when analyzing dna of a person? If you want to store them in a database, what type of field you will need (text,number,hex)? And what should be it's length?
4
votes
1answer
78 views

How much cost would artificial pollination add to common products (fruits etc.)?

I've read about ecosystem services and their possible valuation - statements like "honeybee pollination service in the US is worth 1.6 billion dollars". Is data available on how this would affect the ...
2
votes
1answer
60 views

How is it decided that one drug is better than others by X times?

I read in Tortora and Derrickson that : Enkephelins are 200 times powerful than morphine in their analgesic effects. I wonder how exactly researchers arrive at a number (like 200 here). I also ...
2
votes
0answers
213 views

Saltatory Conduction Of Nerve Impulses

I am aware about some basics of Saltatory conduction of nerve impulses. I know that the nerve impulses(ionic flow and the depolarization) are transferred from the node to the node in myelinated nerve ...
2
votes
1answer
57 views

About validation process of phenological study

I have recently done a phenological study using remote sensing techniques. Now I need to validate my results and my methods, that is, to determine if the phenology estimated from remote sensing is ...
3
votes
1answer
76 views

What is the correct medical procedure(s) for taking a resting heart rate?

Note: I thought the Biology stack exchange would suit this question better than the Fitness stack exchange. Please let me know in the comments if this is not suitable here. I am interested in ...
1
vote
1answer
686 views

Shine-Dalgarno sequence and expressing proteins

Shine-Dalgarno sequence present in the prokaryotic mRNA plays a role in initiation of translation. In eukaryotes a Shine-Dalgarno like sequence is present but does not play an important role in ...
6
votes
2answers
70 views

What features cause mechano sensory adaptation?

In relation to mechanoreceptors (e.g. pacinian corpuscles), what stops a constant stimulus from producing action potentials? I understand that adaption is used to filter out stimuli that aren't ...
2
votes
1answer
81 views

Plant tissue culture [closed]

Tissue culture means that cells are propagated and multiplied under controlled conditions. Suppose the following situations: a) A seed being is embedded in an Agar medium and germinated under ...
8
votes
1answer
113 views

Neuroendocrinal mechanism of parturition

My book reads, "The fetus signals that it is mature by secreting certain hormones that diffuse across the placenta into mother's blood and cause the secretion of oxytocin from her posterior ...
3
votes
1answer
806 views

Why are people tired after surgery?

I had surgery when woke up I felt like I only had 20% energy & felt extremely tired. Is this a common sensation? Why do people feel so tired after surgery?
1
vote
0answers
59 views

Why does the ovum prefers to be arrested at metaphase 2 of meosis before fertilization? What is the possible advantage of this process?

Why does the human ovum prefers to be arrested at metaphase 2 of meosis before fertilization? What is the possible advantage of this process??Please help me with it.
0
votes
1answer
49 views

How to monitor the use of Nootropics?

How do you monitor the use of nootropics? What is a good process to measure both: side-effects and any improvements. Where can I find resources with scientific and tested data of short and long term ...
0
votes
1answer
256 views

Scientific name for the union point of a plant stem and root

Is there a word that describes the meeting point of a plants growing stem and its root? Is this the same term for aerial roots above soil level?
1
vote
1answer
96 views

Terms related to megasporogenesis

Well, I am not able to understand the exact difference between megasporocyte and archesporium. Also I'm not quite able to get, how or precisely from where do these arise? Please help.
1
vote
1answer
82 views

Alpha wave frequency variance in EEG of single subject over period of a few hours?

I have an Emotiv EPOC (EEG headset: 128 SPS, notch filter @60 Hz, felt saline contacts) I've been playing around with. Over the course of two or three hours using CCA to plot an SNR contour against ...
3
votes
0answers
71 views

What metabolic processes do dormant and ungerminated seeds carry out?

What metabolic processes does a dormant embryo in a seed carry out? Seeds will not germinate, either because of a lack of favourable conditions, seed hibernation, or because of a genetically ...
6
votes
1answer
927 views

Regulation in plants bearing cleistogamous and chasmogamous flowers

In most plants bearing cleistogamous flowers, chasmogamous flowers are also borne by the plants. For example, Viola, Oxalis and Commelina contain both these kinds of flowers.( I am unaware of a ...
6
votes
2answers
1k views

How would constantly growing nails have aided early human?

Nails grow rapidly and constantly, such that without constant artificial trimming they would reach lengths difficult to manage. How did this benefit early humans, say 200kya? Were they used like ...
1
vote
1answer
109 views

Artificial Propagation and it's relation to asexual reproduction

I know that asexual reproduction is also called vegetative reproduction. However I do not understand it's relation to artificial propagation. Is it a technique used for asexual reproduction (the ...
0
votes
1answer
66 views

Seed Germination

Is my understand of how seed germination comes to be and what it entails correct? Seed germination: As the seed matures it loses water and enters dormancy (a state in which it’s metabolic processes ...

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