0
votes
2answers
59 views

What is the frequency distribution of each base in a DNA sequence? [on hold]

Can we say that the frequency distribution of each base in a DNA sequence is equiprobable? After the negative answer; i rephrase: Is there a use case in which the frequency distribution of the ...
1
vote
2answers
32 views

How do prions transmit their conformation to other proteins?

I was reading about prions and many sources say something to this effect: "Prions may propagate by transmitting their misfolded protein state: When a prion enters a healthy organism, it induces ...
-1
votes
1answer
43 views

Does drinking alcohol having UTI may help to kill the bacteria?

It's well known that ethyl alcohol kills bacteria. And amount of alcohol in urine may be detected by EtG tests (as long as 3-4 days after intake). Does drinking alcohol in reasonable amount by ...
3
votes
1answer
41 views

What is a regulable promoter? And how does one regulate it?

I'm reading a patent where they (in S. cerevisae YNP5 strain): downregulate the ERG9 gene by replacing the native ERG9 promoter with the regulable MET3 promoter What's a regulable promoter and ...
4
votes
3answers
83 views

Do transcripts always start and end with exons?

I realized that in all cases of "RefSeq Genes" annotations of hg19 I looked at spliced transcripts start (and end) with an exon. From the annotation there is no evidence of any sequence upstream or ...
0
votes
1answer
38 views

A state model of sodium channels

I am studying by myself Human Physiology. I have encountered the following question: In the following given model of sodium channel with 3 states open closed blocked (which I assume means ...
1
vote
0answers
30 views

How is bilateral asymmetry determined in embryonic development?

What are the mechanisms that ensure consistent left-right asymmetric placement of various internal organs (heart, liver, etc) or consistent left-right asymmetric development of paired organs (brain, ...
0
votes
0answers
8 views

Column chromatography protocol for Alternanthera sessilis to fraction phytochemicals [migrated]

I'm in need to find a column chromatography protocol to fraction phytochemical compounds particularly polyphenols in Alternanthera sessilis Red. I can't seem to find one. Plus this is slightly out of ...
0
votes
0answers
10 views

Is It Feasible to Make Biogas to Run a Fuel Cell as a Science Museum Exhibit? [closed]

I am a volunteer at a local science museum. I want to build a new exhibit wherein biogas is produced and used to operate a fuel cell. Is this a feasible demonstration? If so, can someone please ...
0
votes
0answers
32 views

Wasps a few days after bees? [closed]

It was several weeks ago that I noticed this but I saw wasps(I think they were yellow jackets or hornets since I saw them flying alone and with reddish wings very spread out(more than that of a fly or ...
0
votes
1answer
17 views

Why use RRBS (reduced representation bisulfite sequencing) instead of general BiSeq?

My understanding is that RRBS is used for certain cases. For example, WGBS (whole genome bisulfite sequencing) is limited by repeated sequences. However, many papers seem to use both techniques. ...
-1
votes
0answers
39 views

Why females evolved to be physically weaker than males? [duplicate]

Why have male-female diverged in relationship to strength? What is the evolutionary advantage for this?
0
votes
0answers
18 views

What is the highest number of genes expressed under one T7 promoter?

What is the highest number of genes expressed under one T7 promoter? Also, what is the longest polycistronic mRNA? I am interested in the context of heterologously expressing biosynthetic gene ...
0
votes
1answer
31 views

Why does pETDuet-1 only have one T7 terminator but two T7 promoters?

Why does pETDuet-1 only have one T7 terminator but two T7 promoters (vector map below)? Is there any advantage of having only one terminator? There are going to be two mRNAs transcribed from this ...
0
votes
0answers
9 views

Effective population size of a continuously spread population

Is there any model to calculate (theoretical predictions) the effective population size of a continuously spread population? Imagine for example a population spread over an infinite 2D landscape. ...
0
votes
0answers
22 views

Which proteins cross the blood brain barrier?

Are there any known globular proteins which naturally cross the blood brain barrier as part of their function, i.e., without modification? I'm thinking not just human proteins, but also viral ...
0
votes
0answers
10 views

Effective population size of a metapopulation structured on a grid

Scenario Consider a rectangular metapopulation consisting of $x \cdot y$ demes, where $x$ is the number of deme horizontally and $y$ is the number of demes vertically. The population size per deme is ...
1
vote
0answers
34 views

What happens to the human brain when unconscious?

What part of the brain gets affected and does it harm the brain? Thank you I just needed some extra info for a video I'm making.
3
votes
2answers
73 views

Is “A” inhibiting “B” and vice-versa, a positive feedback loop?

If product A inhibits the expression of product B, and product B inhibits the expression of product A, is this a positive feedback loop? My thinking was to consider the scenario that A starts off ...
0
votes
0answers
9 views

Bacterial Flagella P and L ring act as 'bushing'?

It is often stated that in bacterial flagella the P and L rings act as bushing (like in a motor). I have looked up bushing but can't seem to find a description that would fit in the case of bacterial ...
-1
votes
2answers
86 views

What makes something food?

From my (limited) understanding, animals get energy from food by breaking chemical bonds between molecules. There's a lot of water here [citation needed], so it seems like natural selection would ...
0
votes
1answer
14 views

What is the reason for 'microcytic' anaemia?

I know the causes for microcytic anaemia are Fe deficiency, prolonged inflammation, Thalessemia, Sideroblastic etc. All these logically point to a decrease in Haemoglobin synthesis - either Haeme or ...
-1
votes
0answers
9 views

Cell Lines in Cancer Biology [closed]

Where could I find information regarding cell lines such as A549, MDA-MB 468, MCF-7, Hela etc. with respect to their origin, usage, mechanism of action, specific receptors, advantages and ...
4
votes
3answers
51 views

B-cell antibody production

I've just learned about B cells in immunology lectures and some things are not clear to me. Here's what I know: 1) Apparently, each B cell produces a specific antibody, determined randomly at the ...
2
votes
1answer
64 views

Why cold water results in cough [closed]

I have a pretty simple question which always kept me intriguing since childhood and I couldn't find its precise answer yet. Why do we cough by cold water. Recently I had flu and found very strange ...
-1
votes
0answers
14 views

If spore possesses 10 chromosomes with 20 picogram DNA then calculate the amount of DNA in prophase II?

Options : a) 20 b) 10 c) 40 According to me, it should be 20 because a cell in prophase II is haploid after completing meiosis I reduction division. Also, spores are haploid, so amount of DNA should ...
0
votes
0answers
18 views

Production of energy in the form of ATP is concerned with?

Following are the options : a) Mitochondria b) Elaioplast c) Chloroplast d) Preoxisome e) Golgi Bodies Answer 1 - a) and b) Answer 2 - a) , c) and d) According to me , the answer is 2 because due ...
1
vote
2answers
48 views

Why is DNA Shuffling more efficient than Point Mutation?

In a related post on Biology-SE the following insightful comment was made: The advantage of DNA shuffling over introducing single mutations is that you have to screen fewer mutants and the ...
0
votes
1answer
19 views

Random Mutagenesis vs Directed Evolution as Strategies to boost expression

Do people use random mutagenesis (say using UV) to generate host variants that have high expression of a metabolite / enzyme? I've seen it mentioned as a strategy but it confuses me as to why. How ...
0
votes
0answers
4 views

How can eosin be acidic and negative at the same time? [migrated]

The broadest acid-base definition is done by Lewis and he states that a lewis acid is: "a compound or ionic species which can accept an electron pair from a donor compound." And all the sources say ...
0
votes
2answers
27 views

Spatial dimensions for an animal

I'm reading a review paper. They say: The position of an object in head-centered coordinates (that is, relative to an animal's head) can be defined along three axes: the medio-lateral (radial) ...
1
vote
0answers
34 views

What is the most stable globular protein?

What is the most thermodynamically stable globular protein? I am looking for a small (ideally less than 50kDa) soluble globular protein motif which folds easily/reliably and is known to be extremely ...
-1
votes
1answer
31 views

True or False: Dideoxynucleotide sequence analysis Question

Dideoxynucleotide sequence analysis is a template-directed method that makes use of chain terminators that stop DNA synthesis because they lack a 2'OH group. True or false? Apparently the answer is ...
0
votes
0answers
15 views

What information do bipolar cells encode?

Short version: I don't see what information on-centre bipolar cells are actually capturing. Longer: Actually, the question could be extended to on-centre retinal cells as well, but I'll focus on ...
-1
votes
0answers
11 views

Alkali Biuret Test [closed]

In a Biuret test, the reagent is Copper (II) Sulfate in Sodium Hydroxide Solution as the Alkali. What is the purpose of the Alkali?
-2
votes
0answers
15 views

Why do calluses appear most frequent on ring finger? [closed]

I'd like to make the question a little more specific and ask why do calluses appear largest/most frequently on the ring finger, or rather the palm where the ring finger is. I regularly go to the gym ...
3
votes
0answers
35 views

What happens to the brain during sleep versus unconsciousness?

How does being unconsciousness differ from being asleep and whether it causes breaks in consciousness?
-1
votes
1answer
38 views

How big advantage had a trait have to bring to evolve in the human evolution? [closed]

Yes, I've heard that we have evolved from the common ancestor with primates as intesively, as the chimpanzees. Sometimes I read about some enormously complex traits, evolutionary psychologists think ...
-1
votes
0answers
10 views

How to increase the shelf life of yogurt..?

I wonder though bacteria is still present in it and continue to convert lactose into lactic acid then why does not packed yogurt becomes sour? How these companies increase the shelf life of yogurt..?
1
vote
1answer
16 views

Voltage sensitive dyes technique: What is the underlying measure?

I just discovered voltage sensitive dyes technique: first of all what imaging techniques do we use? And I have seen that figures are labeled with ΔF/F0, what does it stands for?
0
votes
1answer
57 views

Why do many people seem to prefer unhealthy compared to healthy foods?

I don't have any concrete statistics on this but many of us seem to love the taste of food that is unhealthy for us. Over the centuries, wouldn't it have been a non negligible advantage to those who ...
3
votes
1answer
42 views

Why I cannot find dendritic cells in blood smear?

According to many sources including wikipedia, there are haematopoietic stem cell derived dendritic cells in the blood. figure 1 - haematopoietic cell lines - ref Despite of this, when I examine ...
1
vote
1answer
30 views

Deducing amino acid sequence from a DNA sequence

The suggested answer to the question is the following: "M L S C D K S D Stop". I do not understand how they get that result. The question is as follows: An RNA polymerase transcribes the following ...
0
votes
1answer
32 views

Link between NaCl and sulfide reducing bacteria

Could there be any link between the consumption of NaCl and sulfide-reducing bacteria? In my study on mice, sulfide-reducing bacteria (SRB) are more abundant, in high-salt-fed group compared to the ...
-1
votes
0answers
15 views

Has S.aureus ever been used against cancer?

Treating inoperable tumors with bacteria appears to be very effective, albeit being toxic to the patient as well. Has (live attenuated) Staphylococcus aureus ever been used against cancer? If the ...
3
votes
1answer
131 views

What is A in IgA? [duplicate]

What is the significance of letter A in immunoglobulinA? What are the significance of other letters D, M , G, E in diffeternt types of antibodies?
1
vote
0answers
36 views

Are there any studies that suggest an evolutionary advantage of dreaming? [migrated]

I've read the answers to this question. But I'd like to ask if, besides those suggested hypothesis, has anyone ever suggested that the advantage of sleeping could be to allow a profound state of rest ...
0
votes
0answers
13 views

How is the mitotic rate controlled? [closed]

I think by regulating the temperature and pH but im not sure exactly therefore please can anyone give me a detailed structured answer.
1
vote
1answer
33 views

How is excess semen removed if ejaculation does not occur?

There are some attempts to answer the question that I found via cursory Google search, but none of them were appropriately sourced. This site claims that they are "recycled like blood cells", but ...
0
votes
1answer
22 views

Why have multiple alleles for beta chains evolved in certain parts of the world? [closed]

I believe that this could be because individuals may have had interactions with a parasite, for example Malaria, that caused changes resulting in different beta chains. Can anyone explain this more ...

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