0
votes
0answers
31 views

Why is alcohol purged from the body more slowly when we sleep?

It is a popular belief that when you get asleep after drinking alcohol, in the morning you have higher level in your blood than if you stayed awake the whole night. Is this true? If so, why? Is it ...
0
votes
2answers
227 views

Why even if all requirements for natural selection are met, it may not happen?

In the book written by John Endler Natural Selection in the Wild p. 4 it says that even if condition a, b and c are met, evolution by natural selection might occur, [...] , but not necessarily, ...
1
vote
0answers
47 views

In glycolysis, what is the source of the electron that makes NAD+ into NADH instead of NADH+? [closed]

I looked at the formula for the glycolysis reaction. The overall reaction seems balanced, however, I don't see anything on the left hand side of the equation that would provides the electron to ...
1
vote
0answers
8 views

Focusing on flowering plants, are there reasonable explanations why pentaploids would be more fertile than triploids?

For the genus Rhododendron, triploids are sometimes fertile but pentaploids appear to be often fertile. Once Rhododendron seedlings gets above the triploid level, aneuploids not near euploid appear to ...
4
votes
1answer
40 views

Can you knockout specific receptors in an adult?

Sorry I don't have a good understanding of this topic, but I'm guessing that "receptor knockout" is related to/a part of "gene knockout"? And If I understand correctly, gene knockout is currently ...
1
vote
0answers
26 views

Which is better adapted for global warming: deciduous or evergreen trees?

Evergreen photosynthesise for longer and don't lose their leaves all at once, whereas deciduous plants do and enter periods of hibernation during winter, among other differences (correct me if I am ...
1
vote
1answer
42 views

Stabilizing forces between the protein sequences?

we know that Protein structures from secondary to Quaternary are maintained by noncovalent or weak interactions including electrostatic interactions,van der Waals forces & hydrogen bonding. What ...
1
vote
1answer
37 views

Who and when was the first human diagnosed with hemophilia, or considered a carrier?

The earliest case I can find is Queen Victoria of England, who ruled from 1837-1901. Is this the first hemophilia case on record?
9
votes
1answer
139 views

Why aren't plants' roots as diverse as leaves?

I have been doing some gardening recently and I suddenly realised that all plants have superficially identical non-woody roots of the same size from gigantic trees to small fruiting plants and ...
-1
votes
1answer
96 views

Do any dogs have blue iris - not just sclera? [closed]

I was looking in to the question of whether any dogs in fact have "blue eyes"... A quick search gives plenty of information on and images of dogs with blue sclera and black iris. Every "blue-eyed" ...
2
votes
3answers
185 views

Why don't housekeeping genes have TATA Box regions in their promoter sequences?

Housekeeping genes are genes that are continuously transcribed. Like all other genes they have promoter sequences, but they don't have TATA box sequences that are used to specify from where ...
1
vote
1answer
60 views

How exactly are petri dishes used (e.g. in medicine)? [closed]

I know that petri dishes with a growth medium are used to grow micro organisms. I guess this works as follows: The petri dish has to be kept sterile. To make it easier, I guess one could cool it. ...
7
votes
1answer
353 views

What will happen if a foetus is Rh- and the mother is Rh+?

If a mother has Rh-negative blood and her foetus has Rh-positive blood it will result in rhesus incompatibility and lead to erythroblastosis fetalis. What will happen if the reverse occurs, when a ...
2
votes
1answer
93 views

How does waking up from an alarm clock work?

During sleep, one's brain is shut down. All it can do is to see some dreams from the semi-conscious mind. Then how does it hear when the alarm clock rings?
0
votes
1answer
78 views

BLAST(Basic Local Alignment Search Tool) is heuristic?

How can we say that BLAST is based on a heuristic algorithm, as after finding one common word in the query sequence and a database sequence it performs pairwise alignment by dynamic programming - ...
1
vote
1answer
49 views

what are examples of experimental designs on exposing materal for degradation

if one wanted to compare how sources of DNA would degradate in various conditions(environmental) how would they do this in an experimental fashion but also be best comparable to real world examples of ...
6
votes
1answer
121 views

Effect of sex-ratio on the effective population size

As stated on this wikipedia article, the effective population size $N_e$ when the sex ratio differs from $\frac{1}{2}$ is $$N_e = \frac{4N_mN_f}{N_m+N_f}$$ I understand the biased sex-ratio ...
2
votes
1answer
40 views

Are all tastes just a combination of sour, sweet, bitter, etc.?

For example, can the taste of pineapple be isolated to just a certain amount of "salty-taste-triggering-molecules" and "sweet-taste-triggering-molecules" etc.? Can our current understanding of the ...
1
vote
1answer
83 views

Why do we get sleeply after we eat?

After we have eaten, we feel cold and sleepy. I think it's because the maximum blood supply is transferred towards the digestive system so that digestion is done, and therefore the brain to does not ...
-1
votes
1answer
62 views

What are allogametes? please explain [closed]

Allo means different or unrelated I guess.Please clear me the meaning with some examples.
0
votes
0answers
22 views

What Helminth species has the simplest LABORATORY CONDITION for hatching?

I am very interested to hatch the eggs of a parasite in LABORATORY ! but for my first experience I need a species that is not so expensive or time consuming for experiment and can be done by an ...
0
votes
0answers
39 views

Is it possible to change grass colour?

I'm interested in growing grass in a color other than green, the grass can by any typical lawn species (couch, kikuyu, tall fescue, buffalo, etc..) and it'll be grown in a 300mm * 300mm container. ...
4
votes
1answer
46 views

Carl Sagan's ideas on the self-extermination of technological civilizations

I've read (though I can't remember the source) that Carl Sagan speculated that intelligent life forms tend to evolve on various worlds, then exterminate themselves. If true, then I'd like to learn ...
1
vote
0answers
42 views

What are the effects of non-ultraviolet light radiation on DNA?

I am trying better understand the effects of varying the frequency of light on DNA, however, most of what comes up is "UV light" and how it is damaging to DNA (presumably by ionization). Have there ...
5
votes
1answer
163 views

What is the origin of prions?

We know something about the origin of the first cell. But what do we know about prions? How did they originate?
6
votes
1answer
67 views

Is there a model perennial plant species?

Most of plant science is conducted on small annual species with short life cycles; predominantly Arabidopsis thaliana, but also a handful of others like Oryza sativa and Medicago truncatula etc. Is ...
3
votes
1answer
50 views

What are the hairs/spikes on the edges of these leaves for?

Windows 7 has a wallpaper/background which shows an attractive, leafy plant with fine hairs or spikes on the edges. What might these be for, and what sort of plant is it? My initial (uneducated) ...
4
votes
2answers
190 views

Basic Local Alignment Search Tool (BLAST)

Why would BLASTP (Basic Local Alignment Search Tool) be a poor tool to search for motifs in protein sequences?
10
votes
2answers
181 views

Understanding the brain: how are neurotransmitters released in the brain?

I have a basic knowledge of how neural networks work. A potential difference is created that forces sodium, potassium, chloride, and calcium ions to flow which carries an electrical signal to the end ...
0
votes
0answers
25 views

Immunotherapy for tumours which do not have TSA

Is immunotherapy possible for tumours which do not have Tumour Specific Antigens (TSA)? If so, doesn't targeting those tumour cells also target other healthy cells, thus causing autoimmunity ?
-2
votes
2answers
120 views

Why human skin colour disprove natural selection? [duplicate]

Amount of melanin decides the darkness and fairness of skin. The darker the skin is, larger the heat energy it will absorb from sunlight. The lighter the skin is, less will be the heat energy ...
2
votes
0answers
43 views

Is there any mechanical digestion that occurs once food/chyme enters the small intestine?

Does mechanical digestion occur in small intestines and, if so, how does it occur? I found some sources that say digestion happens mechanically and chemically in the small bowel, and others that say ...
0
votes
1answer
80 views

Why is the penicillin/ceftriaxone hypersensitivity test only done once?

I have had a severe bacterial infection. I was prescribed ceftriaxone, and when the time came for injecting it the nurse asked me whether I have an allergy to ceftriaxone. I answered that it's my ...
5
votes
1answer
95 views

Why are fifth order Markov Models, the ones most often used for gene prediction?

As far as we know that smallest polypeptide chain length is 60 amino acids - so if we found an Open Reading Frame (ORF) of about 60 codons without the interruption of stop codon we can consider it to ...
0
votes
1answer
140 views

Why do humans have 46 chromosomes? [duplicate]

Humans have approximately 25000 genes. Why are these genes on 46 chromosomes? Why not 40 or 50?
1
vote
1answer
27 views

Difference Between Gene Delivery and Gene Therapy

What is the specific difference between gene delivery and gene therapy? As far as I understand, gene delivery is the first step of gene therapy, but where does gene delivery end and gene therapy ...
1
vote
1answer
28 views

Do viruses linger/passively transport or attack the body at once?

Do viruses generally attack as soon as they can or do they lie dormant until they reach a cozy spot in the body? Like is it improbable I have inhaled a virus if I do not feel pain in my lungs?
3
votes
0answers
52 views

Diffusion approximation to genetic drift

I am reading from the classical textbook Principles of Population Genetics, Hartl and Clark (pdf here). Introduction Let $f(p,x,t)$ denote the distribution of allele frequency $x$ at time $t$ ...
2
votes
1answer
257 views

Why does the kidney of a cow have lobules, why the kidney of a human hasn't any?

The kidney of a cow has lobules, while the kidney of a human hasn't any. I can't think of any reason why it would be good for a kidney to have lobules. It would be good if the kidney needed to have a ...
4
votes
1answer
62 views

Can a reservoir host act as a vector?

Is it possible to get an infection by contact with a reservoir host ? Can a reservoir host act as a vector ? What is the distinction between these two concepts (reservoir host vs vector) ?
2
votes
1answer
53 views

Can galls be formed from mutualistic relationships?

According to Wikipedia, galls (cecidia) are formed by parasitic insects and mites like gall wasps (Neuroterus albipes). At some metamorphic stage, these organisms alter cell division processes in ...
3
votes
2answers
81 views

How can neuronal signals faithfully be reproduced by scalp electrodes?

There is a skull barrier (and possibly other layers too) between the brain and the scalp. I have seen people trying to extract EEG signals from the scalp by connecting electrodes and interface it to ...
0
votes
1answer
77 views

Does increasing the value of k in k-fold coverage requires more memory?

Study: Here is what is k-fold coverage which is know as sequence coverage. According to this, 2-fold coverage means the whole DNA is sequenced more twice in average. Question: If I have a genome ...
18
votes
2answers
2k views

Can Biologists identify all viruses?

I went to the doctor today with my girlfriend, and the doctor said that she had a virus but doesn't know which one and she should let the infection heal with some rest. The fact that the doctor ...
5
votes
1answer
85 views

Identification of an insect from midwest US

I have been seeing them more and more frequently indoors. I am currently in the Midwest United States, weather has been unusually warm for December, and there are many trees nearby. Can someone ...
5
votes
1answer
75 views

Are surface area or volume conserved during cell division?

I am a student of physics of mathematics with very little knowledge of biology. Nevertheless, I am very keen on biophysics and I'm trying to learn the biological concepts that I need on the way. I'm ...
1
vote
1answer
168 views

sodium chloride and amylase activity

So, I did an experiment on the effect of sodium chloride on amylase. and I found out the higher the concentration, the slower the activity. Therefore, is it valid to make the assumption that when we ...
3
votes
0answers
60 views

What is the advantage of using plant-derived antibacterials rather than bacteria-derived antibacterials?

So obviously we have a big problem with antibiotic resistance. Most of our antibiotics originate from bacteria themselves (or are synthetic variations on scaffolds which originate from bacteria). I ...
0
votes
1answer
46 views

How does the body survive Ebola? [duplicate]

Because Ebola takes over the immune system and uses it to replicate more and more of the virus, how does the body survive? Is it a case of the virus being self-limiting and eventually just getting ...
3
votes
0answers
51 views

Why do I get such a strong background in a detection of DIG-labeled DNA (Southern Blot)?

I have done a Southern Blot Analysis of DNAmt transferred to nylon membranes. The DNA was firstly loaded on a 2% agarose gel. An immunoassay was done to detect the bands using Anti-Digoxigenin ...

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