2
votes
0answers
25 views

Time lapse between fresh blood's exposure to air and that same blood turning darker red-brown [closed]

Sorry that my question is confusing to some and I certainly didn't intend to insult anyone's intelligence, so I'll attempt to clarify: For investigative purposes, I'm searching for a tool that can ...
2
votes
0answers
11 views

Fixation rate at neutral loci

It is a classical result that the expected time for a neutral mutation to occur and to get fixed is $2 N \mu \frac{1}{2N} = \mu$, where $N$ is the population size and $\mu$ is the neutral mutation ...
0
votes
0answers
4 views

What mechanisms exist for the excision of specific sequences from DNA?

I already know about recombinases (specifically excisionases), but was wondering if there were other mechanisms present.
0
votes
0answers
16 views

Can life forms exist from simple structures not made of the four bases?

I understand that all life forms on the planet are made from adenine, gauatine, cytosine and thymine, which chemically joined together to form RNA or DNA (correct me if I'm wrong). This goes on to ...
2
votes
1answer
11 views

What are the total number of action potentials in the human brain?

Is there an approximate figure of the total number of action potentials in the human brain? It's my understanding that there are ~ 60 billion neurons in the brain with ~ 100 trillion connections ...
5
votes
1answer
197 views

How Do White Blood Cells Learn? Or Do They?

So I get the concept that a vaccine is a weakened form of a virus so that the body can "learn" to fight it and make a person immune to that disease, but how exactly does this learning take place? What ...
1
vote
0answers
13 views

Do our ears or brains gradually adapt to noise pollution?

Having lived in various places all over the world for the past 9 years of my life, one thing stood out to me throughout this time, and now in particular. From a quiet place on the countryside in ...
27
votes
4answers
12k views

Why do eukaryotic organisms have introns in their DNA?

We touched on introns and exons in my bio class, but unfortunately we didn't really talk about why Eukaryotes have introns. It would seem they would have to have some purpose since prokaryotes do not ...
0
votes
0answers
13 views

Does malaria have a reservoir host?

Can warm blooded vertebrates other than humans act as reservoir hosts for malaria parasites? I'm mainly interested in plasmodium vivax and possible reservoir hosts in the wider area of Europe/ ...
0
votes
0answers
12 views

Find the probability of Filium (child) that are dark (and) heterozygote

Two mice are crossed and both are dark and heterozygote. Find the probability of their filium(children) dark (and) heterozygote in F1. Here's what our teacher explained: I don't understand. I ...
2
votes
0answers
16 views

What makes substances allergenic?

Is it possible to tell or rule out (potentially a priori) whether any given substance or compound is likely and how likely to cause allergies with high confidence, without the need to conduct ...
5
votes
3answers
175 views

Why do human ears have a lower boundary for the lowest energy perceivable signal than eyes?

I am currently hearing a lecture about human machine interaction. The lecturer is not a biologist (neither am I, we are both computer scientists), but he makes some statements about biology which I ...
3
votes
0answers
43 views

Why do most organisms have negative supercoiled DNA?

It has been observed that in nature most organisms have negative supercoiled DNA and that few organisms have positive supercoiled DNA. Some of the organisms that have the positive supercoiled DNA live ...
3
votes
0answers
47 views

How to tell if a beverage will hydrate or dehydrate?

Beverages of any type generally contain some measure of water. However, in the case of some liquids, the non-water components take more water from the human body to filter out than the water contained ...
6
votes
2answers
315 views

Why deoxyribose for DNA and ribose for RNA?

Why is DNA made out of deoxyribose and RNA made of ribose? Why can't they both use ribose or deoxyribose? I think that the deoxyribose gives an advantage in storing genes, the job of DNA and ribose is ...
0
votes
0answers
8 views

Boiling and melting points of Trans- and Cis- isomers of but-2-ene [on hold]

The boiling boing point of Trans-But-2-ene is lesser than that of Cis-But-2-ene but again the melting point of trans-but-2-ene is higher than that of cis-but-2-ene. Why ?
1
vote
3answers
54 views

What is the relationship between protein-protein interaction networks and metabolic networks? [closed]

I am trying to find out how these networks can be linked together. I know that Protein-protein interaction networks and metabolic networks both fall under the Intra-cellular type of biological ...
3
votes
3answers
97 views

Book recommendations for evolutionary models

I was recently working on getting a statistical model of a DNA sequence. To do this I found that understanding evolution quantitatively seems to be quite important. I would really appreciate any book ...
0
votes
0answers
17 views

Size of the Drosophila melangoaster genome components

How large are: one X chromosome one of each of the major autosome (chromosomes 2 and 3) for Drosophila melanogaster in the following measures? Length of DNA expressed in base pairs e.g. Mega ...
2
votes
0answers
17 views

Degree of dosage compensation in Drosophila melanogaster

In this paper the authors state that the dosage compensation seen in Drosophila is approximately twofold, but they do not provide any source or numbers (as far as I can see) for this. What is the mean ...
4
votes
0answers
25 views

(Why) are polar bears more common in Labrador than in southern Greenland?

The Labrador Sea is between Greenland, Labrador, and Qikiqtaaluk: Map source. A Greenlandic source on polar bears states: In Greenland the polar bear lives and breeds in the northernmost parts ...
0
votes
0answers
61 views

Is there any truth to at-will pregnancy rejection? [on hold]

First and foremost, if you feel intense anger that this question is being asked, I share your anger. The fact is, I just don't know. But I've seen this alleged phenomena used in discussions ...
0
votes
0answers
22 views

Is it safe to refill a PET water bottle? [on hold]

At work, I drink quite a lot of water by refilling a PET water bottle such as this one and it could happen that I use the same bottle for at least two weeks. I know that the plastic might dissolve ...
4
votes
1answer
649 views

Are all dinosaur bones radioactive?

I watching some TV program some time ago and a guy in it mentioned that when-ever museums display real dinosaur bones (as opposed to a replica) the bones are painted over with a lead paint, because ...
2
votes
0answers
42 views

How do I identify the protein with the highest Disulfide bond density? i.e protein with highest ratio of Disulphide bonds per Peptide bond? [on hold]

I want to list all proteins in the protein database and list them by the ratio of number of disulphide bonds per peptide bond. I am not particular about the reliability of identification of ...
3
votes
0answers
34 views

How can E. coli proliferate so rapidly?

The E. coli has a genome with approximately 5×106 bp. The main DNA polymerase involved in its chromosome duplication (DNA pol III , the one with highest processivity) can polymerize ~103 nucleotides ...
1
vote
1answer
19 views

Electroporation of one-cell embryo?

Would electroporation be successful on a one/two-celled mouse embryo? If it would, what buffer could be used and what percentage of cells would be viable? Thank you.
1
vote
2answers
34 views

The Ancient Kingdom of Monera

Why exactly were bacteria and archaea kingdoms separated from the now unused kingdom of Monera? Aren't they the same? They are both prokaryotes, so what is the difference?
1
vote
1answer
73 views

How are 23 chromosomes in human sperm chosen?

I'm not biologist and I have just a basic knowledge. I've been thinking for a long time about the following question: How does the body choose which 23 chromosomes should be active in human sperm and ...
1
vote
3answers
28 views

What is the basic structure of the nuclear lamina

What gives the nucleus its shape is a mesh of intermediate filaments called the nuclear lamina. It forms an interface between the chromosomes and the inside of the nuclear envelope. If these ...
2
votes
1answer
21 views

Are there multiple meanings to “clone” as in “clone a gene”?

I originally thought that cloning a gene meant to put it into bacteria and have them express it. But sometimes I see it used and it seems like it's just a synonym for "identify the sequence and/or ...
3
votes
1answer
15 views

Can virus resistance be acquired through generational exposure?

If I have a squash plant that has a mosaic virus of some kind, and I breed its descendants (via seed) for generations, each with exposure to the same virus, will future generations be likely to ...
0
votes
0answers
20 views

Why proteins are building blocks of life? [on hold]

I like to think that normally C and H are oxidized in the nature. Yet, plants, using sun energy, break the oxigen away and build carbohydrates, like sugar/glucose. Basically, any plant is just bunch ...
1
vote
0answers
38 views

Nutritious protein substance for vitamin enhanced crop?

I am not a bio or science major, but we have a subject, like an elective on biotechnology and we were tasked to think of a product that hasn't been invented yet. My groupmates and I thought of a ...
2
votes
1answer
48 views

How do you determine if donated, stored blood is viable?

Think about stored donated blood; What should we check before transfusing it to a patient, to see if blood is still viable? What methods to use? What components should it have in what levels, to be ...
2
votes
1answer
39 views

Why do haemophillic females $X^hX^h$ die before birth?

I just came across a statement in my book , while reading genetics, that haemophiliac females do not survive till birth (the reason not mentioned here why) . Before posting this question here I ...
0
votes
0answers
22 views

What is considered to be human? [on hold]

Perhaps this isnt the correct forum but ill try none the less. I have two parts to this: 1- What is Human? I struggle to grasp this concept, we are a species but what seperates us from the likes of ...
0
votes
0answers
23 views

What is the probe that absorbs at 450nm in the presence of NADH in this assay?

The colorimetric assays by Biovision and Sigma Aldrich seem to utilise a probe that binds to or reacts with NADH in order to cause absorbance at 450nm which can then be quantified by a ...
1
vote
1answer
64 views

Enzyme Assay - pectinase

During assaying an enzyme at high temperature, the substrate (Pectin) is degraded by the high temperature rather than by enzyme, so, how can I minimize degradation of the substrate by the temperature? ...
-1
votes
0answers
20 views

What is serological profiling

I read an abstract, but couldn't understand many things. These are the follows: 1. What does serological profiling mean? 2. What does stage specific responses mean? 3. "The antibody response from the ...
4
votes
0answers
38 views

Mechanisms of genotype*sex interactions

I'm looking for suggestions of the mechanistic level at which genotype*sex interactions can occur. These give different phenotypes from the same genotype dependent on the sex they are expressed in. ...
4
votes
1answer
98 views

Chaos theory and population cycles of odd periodicity

I have just begun to read about Chaos theory and have come across the statement that "Period three implies chaos." My question: Does any odd period imply chaos or only 3? If so, how can populations ...
3
votes
2answers
30 views

Biochemical coupling between two enzymatic reactions - Enzymes physically associated?

I am wondering what the exact definition of biochemical coupling between two enzymatic reactions is. I know that these two enzymatic reactions have to share the same intermediate(s) one is ...
-2
votes
0answers
15 views

Relation between double helix CGTA and dominant / recessive genes [on hold]

How could I understand the relation BB ~ 25%, Bb ~ 50%, bb ~ 25% of being bald versus CGTA? What has one thing to do with the other?
0
votes
1answer
9 views

Primer design for HLA locus

i have designed primers for HLA locus DPA1(exon 2 region) based on Real-Time PCR (qPCR) Primer Design guidelines. primer will start from intron regions to cover full exonic region. ...
44
votes
5answers
3k views

Life without DNA?

I'm by no means an expert in the field, merely a curious visitor, but I've been thinking about this and Google isn't of much help. Do we know of any lifeforms that don't have the conventional ...
1
vote
1answer
22 views

How would i describe a Cladogram as paragraph? [on hold]

I have this paragraph that i have halfway finished, but i do not know what to put in the spaces. A Cladogram is a branching diagram that represents the proposed phylogeny or evolution of a species ...
4
votes
1answer
197 views

Why AZT is selective towards HIV and doesn't impair human DNA replication?

I've found this article, which is a very old one (from the time when nucleoside analogs where researched as a possible way to prevent replication of virus genetic material, before the HIV epidemics). ...
0
votes
1answer
44 views

if the load is removed from an eccentrically contracting muscle, will it start contracting concentrically?

Geometrically speaking, a muscle contraction should exert a force between the two attachment sites. However, the actual effect of the force on the overall geometry of the body near the point of ...
3
votes
0answers
38 views

How we share pain?

When somebody else tells me about his or her itching or pain in some specific body part I sometimes begin to feel similar feelings. I can think of about three explanations: I feel pain all over my ...

15 30 50 per page