2
votes
1answer
41 views

Very introductory online source of information in evolutionary biology

We receive quite a lot of questions from layman in evolutionary biology in this site that are sometimes difficult to answer just because there is way too much to say. Why don't human keep evolving? is ...
1
vote
2answers
62 views

Why don't we keep evolving until we are super-human? [duplicate]

Humans (homo sapiens) have been on the earth for thousands of generations, and we have kept evolving throughout that time. Why don't we just keep evolving so that, let's say, we live for an average of ...
8
votes
0answers
62 views

Evolutionarily, why do male rats and horses lack nipples?

Developmentally male rats don't have nipples because (reddit) Testosterone release in the fetal male rat happens before the stage of mammogenesis where the teat is formed whereas other species ...
2
votes
1answer
27 views

How does myopia actually work?

This is potentially more or less a question about optics, but I've never been truly satisfied with any explanation that I've been given about Myopia. In fact, I almost can't even believe it. There are ...
2
votes
1answer
33 views

Mitochondrial D-Loop

I know that the D-loop is a DNA complex in which the strands of double helix DNA molecule are separated for a stretch and held apart by a third strand of DNA. Usually, this third strand has a base ...
0
votes
0answers
8 views

Concerning rDNA in cloning, and how to determine the coding strand.

When you create a cDNA library from eukaryotic mRNA, the original mRNA would become the coding strand for the bacterial transcripts. My question is how is RNA Poly correctly oriented one the ...
3
votes
0answers
23 views

Infrared emitting diode eye safety

I'm thinking of creating my own laser tag system and am a bit concerned about the eye safety aspect. Most of the homebrew system I've seen use the TSAL 6100 ...
3
votes
0answers
34 views

E. coli not growing in liquid medium

We are regularly doing bacterial transformation and subculture from plate to liquid media to extract DNA. This usually goes very well and is straightforward, but occasionally, the colonies that grew ...
-1
votes
0answers
10 views

did pteranodons live in colonies?

In one book I read that pteranodons lived in huge colonies. But pteranodon's family in "Dinosaur Train" ( https://en.wikipedia.org/wiki/Dinosaur_Train ) does not seem to be a part of any colony. So, ...
0
votes
1answer
42 views

Why do teeth decay of sugar?

Sugars is a common component in diet of mammals. Why then their teeth did not develop resistence to sugar decay?
3
votes
1answer
27 views

Why MHC class I antigen presentation exist in normal cells?

The book "Kuby Immunology" states that normal infected cells might present antigenic peptides on their surface via MHC class I, but these can't activate naive CD8 cells. Only infected professional ...
3
votes
2answers
211 views

Why are some housekeeping genes considered better?

Whenever a PCR is done, we have to use housekeeping genes like GAPDH, to self normalise the values to account for different starting cDNA/DNA. Now there are many different genes like GAPDH, ubiquitin, ...
2
votes
0answers
19 views

Storing Taqman plates with polymerase in fridge before running

I'm going to be running some Taqman assays on cDNA generated from RNA collected from various samples, and will end up running a bunch of plates (right now the setup is 1/2 a plate per sample, ...
1
vote
1answer
38 views

An example for N50? Why do we need it?

I'm trying to understand N50 on the wikipedia. But I was unable to get a sense of the definition: Given a set of contigs, each with its own length, the N50 length is defined as the length for ...
1
vote
1answer
21 views

specific numbers of neucleotides in okazaki fragments

Why there is specific number of nucleotides in okazaki fragments...? Okazaki fragments are form in lagging strand during the process of DNA replication.
0
votes
1answer
24 views

Without help of Insects, can plants & trees bear fruits & flowers? [closed]

Without help of Insects, can plants & trees bear fruits & flowers?
0
votes
0answers
5 views

Why low variant frequency in exomeseq data (ANNOVAR)?

I've got an annotated ANNOVAR file with 300.000 nucleotide variants of 4 genomes. There's one thing I don't understand when looking at the data: Why are the variant frequencies so low in comparison to ...
1
vote
1answer
61 views

History: Building a “Phylogenetic network” of famous evolutionary biologists [closed]

Seems like many of the famous evolutionary biologists are somehow related to each others. For example (and I might be mistaken), Ronald A. Fisher was mentored by a descendent of Charles Darwin. Joe ...
2
votes
1answer
20 views

What are the units of Phylogenetic Independent Contrasts (PICs)

PICs are a popular phylogenetic comparative method and I was wondering what units the actual contrasts are in. I want to say they are unitless but I am not entirely sure.
3
votes
1answer
30 views

How could I identify whether given RNA-seq data is paired end or single end

I need to have a RNA-Seq dataset and therefore, I've visited the following site NCBI-geo C. Elegans In the Supplemantary file part, I clicked the SRP/SRP051/SRP051702 ftp and downloaded sra file. ...
2
votes
2answers
41 views

How to compute the regression of individual fitness on individual phenotype

Consider a population structured in groups of two individuals. Individuals' interactions follow an additive prisoner's dilemma: \begin{array}{c |c |c|} & C & D \\ \hline \text{Cooperate (} C ...
3
votes
1answer
35 views

Mechanism behind negative conductance of ion-channels

I am struggling to understand negative conductance shown on I-V curves on ion channels. Mechanistically negative conductance means that inward (or outward) current increases when voltage across ...
0
votes
1answer
18 views

What does this mutation notation mean: MAP2K41161fs*12

I received a report that had a mutation notated as: "MAP2K41161fs*12". I'm used to seeing this sort of thing: BRAF(V600E) or BRAF(T1799TA). Can someone tell me how to interpret "MAP2K41161fs*12" ?? Is ...
5
votes
1answer
66 views

Influence of eating at late night on sleep

I have often heard the saying that one shouldn't eat a mountain of food because blood will go to the stomach and it'll be difficult to sleep well because the stomach can't rest at night. I see that ...
2
votes
2answers
32 views

How to conceptualize the action potential?

In my AP Biology class, we were taught that action potentials are not electrical impulses in the same way current travels through a wire. Rather, we were taught that action potentials are changing ...
3
votes
0answers
36 views

Colored water uptake by plants [Rainbow Roses]

We all know cut flowers in a vase with water will drink the water. The water is transported by the xylem and by passing through the cellular walls reaches every plant cell and hydrates it or it ...
1
vote
2answers
59 views

Trying to understand the big picture behind DNA sequencing, alignment and searching

I'm about to start a bioinformatics research project but I haven't any biological background. I know my project is in regards to a performance analysis of DNA sequencing and searching "weapons" like ...
1
vote
1answer
23 views

Are there fish with a double circulatory system?

Our courseware materials say there are such fish, but the internet suggests fish only have a single circulatory system. Thanks!
1
vote
1answer
30 views

Identifying the origin of replication of an unknown *E. coli* plasmid

I have attempted a few searches for a list of origins of replication for plasmids in E. coli, but I was only able to find a list of origins, but not their individual sequences. The available plasmid ...
0
votes
0answers
13 views

Linkage Repulsion

"Segregation distorters such as meiotic drivers, involve two loci—a killer (drive) locus and a sensitivity (target) locus—being in strong linkage repulsion to ensure that the drive and ...
9
votes
1answer
64 views

Why some parts of the human body have immune privilege?

Why have the eye and CNS have immune privilege? Why does the body not develop tolerance against their tissue and instead risk their damage in case an accidental immune cell infiltration? Wiki: ...
0
votes
1answer
31 views

Genetic notations

Genetic testing revealed these two mutations (hypothetically): IVS11+6G>A and IVS11-4G>A Could you please explain every part of this notation, especially "+" and "-" signs.
1
vote
0answers
26 views

What will happen to transcription if histone acetyltransferases are removed from a eukaryotic cell?

If HATs are destroyed in a eukaryotic cell, how will gene expression level be affected? Will all gene expression be affected or just be slowed down and most gene will still be expressed?
3
votes
2answers
56 views

Antibodies stored in freezer instead of fridge

Someone from my lab put the box of antibodies in the freezer instead the fridge. Can I hope that they will still work?
0
votes
3answers
82 views

How does frame-shift mutation not absolutely ruin the organism?

I'm a bit curious as to how frame-shift mutation works. If you shift one amino acid towards another. How does this not affect the entire chromosome? Wouldn't this mean that the organism would be ...
1
vote
0answers
15 views

Linkage Disequilibrium in GWAS

I see a lot of studies on GWAS not filter out for linkage disequilibrium or even make the slightest mention of it. Why is this the case? I would imagine that you want to keep SNPs that are only in ...
0
votes
0answers
28 views

Some kind of better oxygen-transport protein or something… Can you help me find it?

I remember reading about artificial or man-made, oxygen-transport protein that is somehow an improvement on hemoglobin, and that it is possibly immune to sickle-cell anemia, or something... But I ...
1
vote
0answers
47 views

Consuming animals by slaughtering vs injecting barbiturates?

In "Least painful way to die" we get an answer ... Companion animals (e.g., dogs and cats): injected barbiturates are recommended Laboratory animals (e.g., mice and rats): injected ...
7
votes
0answers
66 views

Biopython - Big Discrepancy Calculating RNA melting Temperature over Literature

I experience big discrepancies when calculating melting temperature of RNA 7-mers with Biopython over values generated by a popular algorithm. I tried the nearest neighbour algorithm with RNA and ...
0
votes
1answer
31 views

(Genetics) Is a silencer the same as gene silencing (heterochromatin)?

Is silencer the same as gene silencing? I know that gene silencing refers to those heterochromatin concentrated at the telomeres or centromere. It is also related to methylation. But what about a ...
0
votes
1answer
17 views

Can the Staph streak method be used for culturing Neisseria on blood agar?

What I learned in class: Normally chocolate agar is needed to grow Haemophilus and Neisseria. The Staph streak technique can be used for culturing Haemophilus on blood agar by allowing the Staph to ...
0
votes
0answers
22 views

What is a “NuMA protein”?

I just got out of a lecture on mitosis and this part was incredibly confusing. After searching my textbook it doesn't cover it that well either. The professor mentioned a NUMA protein that is ...
1
vote
0answers
35 views

Importance of organic chemistry in biochemistry/molecular biology? [closed]

I'm halfway through my biochemistry and molecular biology degree in Australia and i'm concerned about a lack of organic chemistry. My friends studying biochemistry back home in Canada take units upon ...
3
votes
0answers
40 views

Neural coupling between Pinsky-Rinzel (reduced Traub) neuron with a Wang-Buzsaki neuron?

I have read two papers related to modeling neurons. The first one is the paper by Pinsky and Rinzel and the second one by Wang and Buzsaki. The first mentioned neuron model is a excitatory neuron ...
1
vote
1answer
39 views

Limited space for animals - how is that bad?

I am writing an English paper wherein I have to appeal for change in the way humans treat wildlife. I was initially given a situation wherein I took a ferry in a certain area and saw a dead baby ...
3
votes
0answers
29 views

Is the number of stamens always 9 for geranium?

We are studing in class the reproduction of plants. We start the lesson by observing some components of flowers, it was the Géranium. First of all we start counting the number of sepals , petals and ...
0
votes
0answers
25 views

Determining the percentage of the query of an alignment from a BLAST output

Given this BLAST output, how can I determine the percentage of the query sequence in the alignment? I know that it's also referred to as 'query cover' but I can't seem to find anything online that ...
0
votes
0answers
14 views

Over what range do Thyroid Stimulating Hormone (TSH) levels tend to fluctuate over the course of a day?

I understand that the majority of doctors consider the TSH test "the gold standard" for measuring thyroid function (examples stating that literally are here and here). The reference range for what is ...
1
vote
1answer
25 views

How does inbreeding depression cause infertility?

My textbook states that repetitive self-pollination in the plants cause inbreeding depression which causes infertility thus plants develop techniques called outbreeding devices to encourage ...
2
votes
1answer
57 views

Are there any examples of how to apply evolutionary models?

Apologies if this question it too open-ended; evolutionary biology is not my primary field. I have been reading a lot about the use of statistical mechanics in analyzing evolutionary dynamics. As an ...

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