2
votes
3answers
96 views

How to define “evolution”?

The standard answer to: what is evolution? is: It is a change in allele frequency over time! I believe a complete definition should encompass the following concepts: mutations copy ...
2
votes
1answer
69 views

What is one Botulinum toxin medical unit?

How many Botulinum toxin molecules or grams are contained in one medical unit of Botox?
1
vote
1answer
125 views

Standardized Selection Ratio (SSR)

In this article the athors used the Standardized Selection Ratio (SSR) in order to infer what is the preferred host (anemone) of anemonefish. Here is a quotation coming from their methods: ...
3
votes
1answer
85 views

Why does hypertension occur in obstructive sleep apnea?

What is the physiological mechanism behind systemic hypertension resulting from obstructive sleep apnea?
1
vote
1answer
260 views

Microarray gene expression matrix format

After scanning the microarray chip we get RAW data with different formats depending on the type of microarray used. However, these RAW data files can be normalized and processed to generate gene ...
1
vote
0answers
88 views

Workflow for batch analysis of ROI in histology samples

This is a pretty big task, and I have several work-arounds, but I am looking for an efficient way to go from PAS stained slides of lung tissue to defined ROI's over the whole slide (presumably via ...
3
votes
1answer
65 views

mRNA with Pseudouridine and 5-methylcytidine?

I am making mRNA by in vitro transcription for transfection purposes. There is a lot of literature about how protein expression is increased and innate immune activation is decreased by substituting ...
5
votes
1answer
175 views

Definitions and examples of some math-releated ecology branches

I would like to have an example of application and a brief description/definition (two or three lines) of the following fields. I would like to understand the exact differences between them. Other ...
3
votes
1answer
683 views

Index of ecological niche overlap

For this question I am interested in the Pianka's Index of ecological niche overlap. What is the Pianka's Index? How does it work? How can one calculate this index? How often is it used? In what ...
4
votes
0answers
99 views

At which step apply a detection filter when preprocessing microarray data? (Before/After normalization, batch effects removal)

I am trying to understand what is the best practice when preprocessing microarray data using a detection filter (on scanner p-value). Suppose I have a microarray dataset that I have to normalize with ...
1
vote
0answers
106 views

Which is the best way to fix and preserve comet assay slides before staining with Ethidium Bromide?

I want to use the method of Single Cell Gel Electrophoresis (comet assay). I have many samples, but I don't have the appropriate microscope. So I have to preserve my slides until the time comes for ...
3
votes
2answers
3k views

Difference between CDS and cDNA

What is the difference between Coding Sequences (CDS) and cDNA? Are Coding sequences the sequences that is transcribed to mRNA and cDNA in contrast DNA obtained by reverse polymerization of matured ...
5
votes
1answer
336 views

Do ants within a colony ever fight or come to conflict?

I'm investigating how hierarchical groups of a larger organization with a common goal tend to come to conflict with one another over time. As you decompose a large group (for example a corporation), ...
3
votes
1answer
82 views

Transposons and the net amount of DNA

The retrotransposons and certain DNA-transposons, are "jumping" sequences which may be incorporated elsewhere in the genomic DNA of an organism, through varying mechanisms. This insertion is almost ...
5
votes
1answer
171 views

Measuring algae growth or death

My daughter (10th grade) is doing a science fair project on the toxicity of triclosan for the algae Selenastrum capricornutum. She is wondering the best way to measure the effect, given the limited ...
2
votes
0answers
226 views

Image Processing Suite for bacterial microscopy: Schnitzcells or MicrobeTracker?

I am looking to start doing some work tracking the size and growth of individual bacterial cells in the microscope. In order to analyze the images I need software that can segment the cells, ...
4
votes
1answer
281 views

Are wild cats the same species as house cats?

I thought that the definition of species is "can interbreed" From Wikipedia: The wildcat (Felis silvestris) is a small cat found throughout most of Africa, Europe, and southwest and central ...
1
vote
2answers
148 views

Which statement about phenotypic plasticity is false?

This was a test question, and I'm not too sure about the answer. Which statement about phenotypic plasticity is false? a. Because the plasticity of a phenotypic trait may be costly to maintain, it ...
4
votes
1answer
60 views

Generalism - specialism index in microbial ecology

I am doing research in Lipid metabolism in different yeast species and I would like to look into ecology of them. I would like to classify them to a Generalist/specialist based on different ...
5
votes
2answers
131 views

Measuring fitness / lifetime reproductive success (LRS) in Drosophila

I am planning a fitness assay of Drosophila melanogaster. I'd like to get a good measure of lifetime reproductive success (lrs) but I don't want to count all the offspring produced over a lifetime by ...
1
vote
1answer
331 views

How to determine if a plant is autotrophic or heterotrophic?

How do you determine if a plant is autotrophic or heterotrophic, and are there any traits in particular that can be used to classify species? As two examples, how should Melampyrum pratense and ...
0
votes
0answers
44 views

Is there a limit to how much concise information a human can learn adequately? [duplicate]

Like, I am trying to learn more chemistry, but also computer programming from the higher-level programming methodologies, frameworks, languages, APIs, XML, web development, and I'm also hoping to ...
2
votes
0answers
44 views

Shortest route for a Nitrogen atom from fossil fuel to a protein in your body? [closed]

Millions of years ago fossil fuels originated from plants. A nitrogen atom from fossil fuel is now inside in a protein molecule in your body. What is the shortest path that the nitrogen atom ...
2
votes
0answers
25 views

How closely correlated is the level of an snRNA with the level of its corresponding snRNP?

Let's say I am growing cells under two conditions, and let's say I measure U1 snRNA levels in both using digital PCR. If the U1 snRNA level is reduced in one sample, how safe is it to say that U1 ...
5
votes
1answer
141 views

Strange looking mushroom found in a dead tree

I'm trying to identify this mushroom my sister found at her campus' lawn. It is brown, looks somewhat like a turtle or a brain and is growing inside of a dead tree trunk. Geographically the campus is ...
1
vote
1answer
136 views

Energy flow in an ecosystem

What are the mistakes in here? The image below shows a part of the energy flow diagram in an ecosystem. 1. Part P of the biomass of the primary producers does not get consumed. Give a concrete ...
3
votes
3answers
189 views

How to learn molecular biology through pubmed research articles?

Instead of using a textbook, is there an alternative curriculum, that simply lists a set of pubmed research articles for each topic covered in a typical undergrad molecular biology course? I am ...
1
vote
1answer
272 views

Genetic variation and sensitivity of wild cabbage

1: Is it true that the genetic variation of kale plants is smaller than wild cabbage? I think so, because of human selection of the kale plants. 2: Are broccoli and cauliflower more ...
0
votes
1answer
93 views

Which mountain range was formed first (historically) and which the pedigree is correct?

Source 1: Source 1 shows a map of a particular area. In this map you will find the mountain ranges 1 and 2, the species P, Q and R. Two possible pedigrees of the ancestral history of the species ...
2
votes
1answer
71 views

What happens during a Raynauds episode?

Raynaud's phenomenon can be a serious health issue, as the blood flow to the extremities, mainly the fingers is compromised, causing fingers to blanche, and then turn blue. Severe Raynaud's can cause ...
7
votes
1answer
2k views

Difference in length of Okazaki fragments

The length of Okazaki fragments in the lagging strand is about 100-200 nucleotides in eukaryotes and about 1000-2000 nucleotides in prokaryotes. What (molecular mechanism, enzyme type ) ...
1
vote
1answer
168 views

At what temperature does DNA re-anneal?

If primers weren't present in PCR at what temperature would DNA re-anneal? I am wondering how primers manage to bind on DNA strands before DNA manages to anneal back together.
2
votes
1answer
167 views

Growing crops on the Moon

The short version of my question is this: It's some time in the future. I go into my back garden and focus my telescope on the Moon. The surface is virtually covered with giant greenhouses, ...
2
votes
2answers
124 views

Image analysis of GFP-tagged protein localization bursts

I'm reading an article (full text here) that analyze the dynamics of localization of a GFP-tagged transcription factor (Crz1) over the time at the single-cell level, by taking movies in a fluorescent ...
1
vote
1answer
109 views

Why does ice reduce swelling?

It is common practice to use ice packs on injuries that cause bruising and swelling. It seems to be an effective method to assist in reducing swelling. Why does ice reduce welling?
2
votes
1answer
66 views

Is the book “Bioinformatics for Geneticists” outdated?

I am going to be working with genetics data in my organization's data warehouse next year and helping our biotechnology department. I work in academic research, but I have very little genomics ...
2
votes
1answer
955 views

Do bigger animals have more testosterone?

I was wondering the other day outside, thinking about varieties of species and their aggression levels, etc. I had a theory that since these highly aggressive, powerful, and viciously advantageous ...
3
votes
1answer
57 views

Common Ancestry of ETCs and ATP Synthase complexes

Rickettsiales are widely regarded as the ancestor of eukaryotic mitochondria through endosymbiosis. Cyanobacteria are widely regarded as the ancestor of eukaryotic chloroplasts through endosymbiosis. ...
0
votes
1answer
438 views

Which surfaces contain no epithelial tissues and which epithelial tissues are vascular?

Epithelial tissues are found on all the surfaces of the body; including external surfaces and surfaces of organs etc. Are there any surfaces which do not have epithelial? I have read in my book that ...
0
votes
2answers
87 views

Is the poly(A) tail added while transcription is still underway?

I read in Campbell that ....splicing and poly A tail addition may also occur while transcription is still under way. How can the poly(A) tail be added while transcription is still going on?
1
vote
1answer
2k views

Why is the function of lacA (encoding thiogalactoside transacetylase) not clearly understood?

It's almost half a century since the lac operon was discovered but isn't it weird that the precise role of transacetylase isn't clearly understood ? Here a wikipedia article with a link to a journal ...
7
votes
1answer
4k views

Why is ATP the preferred choice for energy carriers?

Why is ATP the most prevalent form of chemical energy storage and utilization in most cells?
0
votes
1answer
81 views

Are there any enzymes in cytoplasm to help the newly-synthesized polypeptide to form tertiary structure?

Polypeptides made by ribosomes which attach to rER will go into the rER to form the tertiary structure. Those polypeptides made by free ribosomes usually stay in cytoplasm. So are there any enzymes in ...
1
vote
1answer
90 views

Attaching suspension cells to coverslip duing mycoplasma contamination detection

I am planing to screen my cell cultures for mycoplasma contamination using the Hoechst 33258 DNA staining method. This method is suitable for adherent cultures. Is this method suitable for ...
1
vote
1answer
92 views

What in neurons and their connections changes during the process of learning?

I'm not sure if this question belongs more in physics or biology (or maybe even computer science)... but biology seemed to fit more. What changes in the state of our brains when we learn things? ...
3
votes
1answer
951 views

How does blue white screening work in selecting E coli that have taken up a plasmid vector?

The plasmid vector I am referring to is pCR 2.1 - TOPO. I added the vector to the E coli and plated them up onto LB+amp+X-gal plate, then incubated. After incubation the plates had two types of ...
1
vote
0answers
63 views

Why did the yeast rise?

Here are the notes I made for an experiment I was doing (I didn't put it here as it is too long) (please ignore the numbers at the end of the pdf file) The graph looks like this: As you see on ...
2
votes
0answers
51 views

Is an antivenom venomous?

What happens when someone takes an anti-venom for an animal they weren't bit by, either for incorrect identification of the animal they were bit by or if they weren't bit at all? I am looking for the ...
6
votes
2answers
7k views

What is the difference between local and global sequence alignments?

Obviously there are a bunch of different alignment tools out there, and I don't want to get bogged down in the maths behind them as this differs from software version to version. I am aware that ...
2
votes
1answer
36 views

Function of an VEGF inhibitor in the treatment of macular degeneration

I'm working on a short presentation of treatments of macular degeneration for a biomedical optics seminar on macular degeneration. Since I don't have any relevant medical or biological background ...

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