4
votes
1answer
258 views

how is the plasma membrane repaired after endocytosis?

When the vesicle is swallowed of course the lipid layer internalizes. My question is how will the top segment of membrane will bind back together when that vesicle took the membrane with it inside ...
2
votes
1answer
60 views

H O N C alternatives for organic life?

Most organic structures built from hydrogen, oxygen, nitrogen and carbon. They are represent 1-,2-,3-,4- bond relations (chemical valence) which allow to build variety of chain structures. Are there ...
1
vote
1answer
51 views

What does “developmentally programmed” mean?

What does the term "developmentally programmed" mean? I can't seem to find a definition anywhere. What would the alternative (i.e. not developmentally programmed) imply?
7
votes
1answer
3k views

Why aren't organelles considered alive?

I'm taking a 3-week Bio I summer course, and my textbook says the cell is the smallest/basic unit of life. I asked my professor why organelles aren't a living unit, and her reply was that they aren't ...
3
votes
1answer
328 views

Antihistamine's effect on insulin secretion and tiredness

Antihistamines are known to cause tiredness. The essential hormones of the body are insulin (glucose), parathyroid hormone (calcium) and aldosterone (Na-K ATPase, sodium). I am thinking how this ...
3
votes
1answer
388 views

Will the increase in atmospheric carbon dioxide lead to larger insects?

From my understanding, the increase in atmospheric carbon dioxide will also increase oxygen levels. That makes me wonder if in the near future insects will grow larger than they are today, since their ...
2
votes
1answer
1k views

What's the physical meaning of Svedberg unit?

Sedimentation coefficients, using a centrifuge, are expressed using Svedberg unit (symbol S, sometimes Sv). Wikipedia states that $S = 10^{-13}$ sec but I also saw in a book that actually $S = ...
2
votes
0answers
60 views

How well does the event-driven DVS sensor approximate the rods of the retina?

There is a neuromorphic vision sensor that is generating some interesting research these days that is called the Dynamic Vision Sensor. One of the claims of this sensor is good approximation of the ...
4
votes
1answer
82 views

Is this ventricular tachycardia?

I am investigating the public data of this. Its specification ...
0
votes
2answers
391 views

What makes us all different and similar to some extent? [closed]

It is said that genes define how we look physically and psychologically; so for example if a male human sperm carries a certain number of genes, say x, and a female carries y, then mathematically ...
0
votes
1answer
74 views

Tc and Th1 interaction and viral immune response

Tc is T cell which can give T killer cells and T helper cells. T helper cells (Th1) see the pathogen presented by antigen presenting cells (dendritic cells and macrophages). They then secrete antigens ...
1
vote
1answer
45 views

Why doesn't the avocado turn brown when it is kept with its seed?

Why doesn't the avocado turn brown when its kept with its seed? What does the seed release that slows down the oxidation process?
5
votes
1answer
90 views

Base Substitution Probabilities Derivation

In Felsenstein's 1981 Paper Evolutionary Trees from DNA Sequences: A Maximum Likelihood Approach, he describes (in equations (6) and (7)) a derivation of the equation of the probability of a ...
7
votes
1answer
500 views

On average how many genes / alleles do people share?

I am curious about how much more a child can be alike to one parent than the other. If a child were to inherit all the alleles that are shared between both parents from one parent, but inherit all ...
4
votes
1answer
702 views

Why Only DNA can Contain Hereditary Material?

Well I'm well aware that it is proven that DNA contains genetic material via transformation and Hershey-Chase Experiment of T2 bacteriophage. Still I was wondering what is the reason only DNA ...
2
votes
1answer
44 views

Effects of having too much vitamin D?

I saw there was another question about vitamin D; however, I do not believe this is a repeat. What are some of the effects/side effects of having too much vitamin D in your body?
1
vote
0answers
49 views

Vitamin D oral intake, transportation and absorption

Several factors affecting vitamin D and its active form absorption and storage acidity of stomach (not significant effect) cytopathic effects of viruses cytopathic effects of bacteria where the ...
4
votes
2answers
7k views

Why do ladybugs have a different number of points on their backs

Everytime I see a ladybug I ask myself this question. Why does every ladybug have a different amount of points on its back? Is it because of its age? Or because of its genes? Is it inheritable?
2
votes
3answers
855 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
2answers
446 views

Do immortal organisms exist?

Do organisms exist that are able to live indefinitely if they are not killed by external factors? Under external factors I would consider things like predators and natural disaster but not illness by ...
0
votes
0answers
26 views

Prenatal hyperkinetic dysfunction and its effect on endurace

Do people with an hyperkinetic dysfuntion have a better endurance? Are they fitter in cause of their Dopamine-overdose or any other reason? I have a case, where someone does not do any sports, but ...
3
votes
1answer
47 views

The use of proteins in memory creation

I have very limited knowledge of how the human memory works as I think, at this time, most people do. However, I have been reading and some articles which say, and I quote the article just linked ...
0
votes
1answer
114 views

Color van der waals bonds in swiss PdbViewer

I'm trying to color certain amino acid's van der waals bonds as in the following picture: can anybody please describe the steps to accomplish that?
1
vote
1answer
45 views

Detecting Calcified stones and cracks in tooth

I had a dental problem when my first molar broke some months ago and after some decay and pain I am undergoing a dental treatment. The doctor was performing a root canal and kept on talking about ...
1
vote
3answers
89 views

Definition of species - location of gene

I know that species have been classified on basis of reproduction , DNA similarity , niche, etc. Has there been a classification based on locus of genes ? What are the drawbacks/shortcomings of ...
1
vote
3answers
3k views

Why do our eyes close when we sleep?

Why do our eyes close when we sleep? Is it to relax our eye muscles? How can it be explained from an evolutionary point of view?
1
vote
2answers
131 views

Gene perturbation, what is it used for, explain to computer scientists? [closed]

I am trying to build a gene regulation network, and I need some basic knowledge of it. So, in gene research, we perturb genes. Such as knock down them? Can people tell 2 or 3 experiment methods to ...
6
votes
3answers
151 views

What is the potential function of ultra-conserved elements in the genome?

If selection pressure results in conservation of DNA sequences, what is the most plausible explanation for the existence of ultra-conserved elements (refs here and here) given that there hasn't been ...
3
votes
2answers
148 views

Is there an evolutionary explanation for the black spots around a pandas eyes?

I couldn't seem to find one elsewhere, at least not with a scientific source. It would seem as it's quite a striking feature there would be an advantage it would infer.
3
votes
1answer
145 views

dopamine paradox in Schizophrenia

If there is more dopamine action in the mesocortical pathway in Schizophrenia, then the patients should always be in euphoric state. But instead patient lacks motivation and don't want pleasure. Why?
6
votes
1answer
4k views

What causes adenosine build up in the brain when awake?

Adenosine is an important hormone in sleep regulation. It is postulated that when a person is awake, there is a build up of adenosine in the brain, which inhibits the neurons in the brain, and ...
2
votes
1answer
48 views

Drosophila grey / yellow

I am studying biology by myself via distance-learning. I have been trying to solve the following problem for a while now and hoped you could help me. As this is "homework" I would appreciate hints ...
4
votes
2answers
2k views

No bands show up in gel electrophoresis, not even marker

I haven't seen any gel lanes in neither my PCR samples nor the marker itself when photographing them. This is not my first time performing 1.2% agarose gel electrophoresis. I see gel lanes when I ...
2
votes
1answer
131 views

“selective pressure” or “selection pressure”?

Editing a manuscript of mine, a co-author changes "selection pressure" to "selective pressure". Are those two terms interchangeable? Or are there subtle differences that I'm not aware of? The ...
3
votes
1answer
114 views

Is there a hormone combination that makes humans grumpy?

Imagine a typical situation that is likely to give rise to a bad temper within an individual: a person is awoken very early in the morning by a sound of a lawn being mowed next door. Unlike expected ...
0
votes
1answer
57 views

How many chemical species are on average in a typical plant and animal cell?

I want to know what sort of range there is on the number of different chemical species in a typical plant and animal cell. Failing that, some specific examples (with sources please). Thanks
3
votes
1answer
5k views

What is a suicide plasmid?

What is a suicide plasmid? Example: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2737453/ mentions a "suicide vector". See also ...
1
vote
0answers
37 views

Study case of the inheritance system of Oenothera

I've been told some interesting facts about oenothera. Apparently in this species some lineages have been through some translocations and in results to these translocations and in consequence, some ...
2
votes
2answers
67 views

In genome research, what is the problem in Mapping that may be caused by reads being too short?

In the following scenario: You were given short sequence reads of plant RNA obtained from a next-generation sequencing machine (fragments of 20–30 nucleotides in length). You attempt to map them back ...
0
votes
1answer
38 views

What information do microarray image convey?

OK I have read that a cell generates 4 kinds of digital (to be precise discrete) data namely DNA, RNA, Protein (sequences that can be encoded as string sequences of nucleotides/ amino acids) and micro ...
0
votes
0answers
55 views

What is the current scientific position on the issue of human race? [duplicate]

Race is perhaps one of the most controversial and sensitive issues in anthropology, biology, and other related fields. As a non-scientist, I've used google to probe the disparity between the positions ...
2
votes
1answer
306 views

Are Bovine serum albumin, Avidin, Ficoll-70 and Dextran-70 positively charged or negatively charged? [closed]

Bovine serum albumin, Avidin, Ficoll-70 and Dextran-70,are they positively charged or negatively charged ? And which other solvents can be used as a substitute to water for preparing solutions in each ...
1
vote
1answer
55 views

To diagnose osteomyelitis of vertebral column in chronic kidney failure

Assume you suspect amyloidosis because of the history of the patient: problem with vertebral column and "purulent" (serous, fibrous, or hemorrhagic) inflammation when patient very young. Now, the ...
3
votes
1answer
87 views

Is there a molecular basis to intelligence?

Is there any explanation, gene(s) or whatever detected, that are co-related or explicitly related via mechanical bio-molecular (or at any other level) models that explain the higher or lower ...
0
votes
0answers
17 views

How is the nasal secretion system of local immunity coupled with lymphatic circulation?

I started a thread about Nasal chronic Inflammation after influenza virus here. However, I do not understand enough well the structure of the nose to answer the questions there. I know that the lysed ...
2
votes
1answer
2k views

Why does hemoglobin's affinity for oxygen increase if an organism lives at a higher elevation where oxygen is lower?

Wouldn't its affinity for oxygen decrease because the acidity of the body would increase with the lack of oxygen? The textbook said otherwise though and I don't understand.
4
votes
2answers
230 views

Do miRNA and antisense RNA do essentially the same thing?

Don't they both just disrupt RNA so it can't make a protein? If so, then what is the difference between the 2?
1
vote
1answer
73 views

Fastest and slowest action potential

When our instructor asked us about the speed of action potentials in cells, I told him that action potentials and two-wheelers travels at similar speeds. He thought that this is an 'interesting' way ...
0
votes
1answer
62 views

Enzyme kinetics [closed]

I can't understand how to study enzyme kinetics. Say I have a lipase and want to study the kinetics of this lipase using a fluorogenic substrate, how would I do this? From what I understand I would ...
1
vote
1answer
38 views

To determine no beating cardiomyocytes from ECG or video recording

I am trying to find data and some method by which I can see and say that there are some cardiomyocytes not working. I have reviewed many arrythmia data where I think I can see much cardiomyocetes ...

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