2
votes
1answer
127 views

How does alternative splicing work?

I am trying to find out what controls what exons are spliced out, and I keep coming across the term cis regulator, but I cannot seem to find a clear explanation of what happens... Thank you in ...
2
votes
1answer
776 views

What are microRNA, siRNA and antisense RNA?

From what I understand, microRNA binds to proteins which can cut certain mRNA strands do that this protein is not synthesised. This seems like gene silencing to me, however I have also come across the ...
1
vote
1answer
30 views

RNA-Polymerase III transcribed genes

I have a list of differentially regulated genes from a high-throughput experiment of the human genome. I would like to find out which of these genes are transcribed by a RNA polymerase III and which ...
4
votes
2answers
2k views

What's a protein pulldown assay?

I'm reading a paper and the authors mention a "protein pulldown" assay. I've never done this before, and googling doesn't bring up much. Could I get a rundown of the basic theory behind it? Also ...
1
vote
1answer
46 views

What are the roles of cadherins in epithelial mesenchymal transitions? [closed]

I know that cadherins control the expression of cancer cells involved in the epithelial-mesenchymal transitions, but I was wondering exactly how the process worked.
2
votes
1answer
266 views

Relationship between leaf structure and Photosynthesis rate

We can see numerous leaf structures in plant kingdom. As the leaves are designed for photosynthesis, their structure must be a factor for any optimization in photosynthesis or chlorophyll ...
4
votes
1answer
180 views

Nomenclature of genes and proteins

With respect to this paper: Identification of Host Proteins Required for HIV Infection Through a Functional Genomic Screen In the abstract, I found names such as Rab6 and Vps35 and TNPO3. So Rab6 ...
3
votes
1answer
54 views

Introducing novel genes to an adult multicellular organism?

Is it possible to introduce a novel gene into the genome of every cell (or at least most cells) of an adult multicellular organism? How would this be done? Thanks, CDB
1
vote
1answer
114 views

What, if any, diseases do larder beetles carry?

I found one of these beetles on my bed as I was attempting to get in. I'm 80% sure my cat carried it in (I found it in the exact same space he had been sitting ten minutes previously). My question is ...
2
votes
1answer
48 views

Can anyone identify this mystery caterpillar?

I found this caterpillar in in El Cerrito, CA and was wondering what kind it is?
1
vote
1answer
40 views

Enzyme\Protein amounts in cancer

I am searching for source, that providing information about enzymes\proteins, in different types of cancers, that their amount in cell is significantly higher - comparing to normal, healthy cell. ...
7
votes
1answer
944 views

Why are there no known photosynthetic archaea?

I'm taking a microbial physiology course and we noted that, while some archaea are phototrophic, there are no known photosynethetic archaea. Are there any physiological characteristics that make ...
2
votes
2answers
296 views

Is it possible to train allergic resistance by exposing yourself to allergens?

My hypothesis is that one can decrease the allergic reactions over time by continuously exposing yourself to slowly increasing doses of allergens. Is there any scientific evidence pointing this right ...
23
votes
3answers
4k views

Do all organisms have to die?

I understand (a little) that there are biological clocks and reason that after a certain amount of time organisms die. I'm wondering if that is something inherent in our DNA or in biology/chemistry in ...
2
votes
1answer
90 views

Is Norway spruce (Picea abies (L.) Karst.) isohydric or anisohydric species?

Question from a thesis defense list ask me this. But I can't find the exact answer on the internet or in books. In my thesis, I described isohydric plants, for example maize, lupin, pea, poplar. This ...
6
votes
1answer
807 views

Are gene variants at different loci also called alleles?

I think the title says it. I always read that alleles are gene variants at a given locus, which confuses me. Thanks!
2
votes
1answer
90 views

Monochromator in fluorescence microscopy [closed]

I'd like to ask why are there no fluorescence microscopes that use a monochromator instead of filters? If there are any, then I should change my question as, which ones use it and why are they so ...
1
vote
1answer
65 views

What is the minimum functional biological light sensor? [closed]

As a follow up to this question regarding the evolution of the eye, it was suggested that primitive eyes only needed to evolve a light sensor and could perhaps use the existing biochemical cascade ...
5
votes
1answer
65 views

Is it possible to isolate and analyse intermediates of protein folding?

I would like to know if there is an assay which could allow us to analyse a protein before it has assumed its 3D functional form. While studying structural biology, I only came to know the forces that ...
6
votes
1answer
213 views

Why do some bacteria have most genes on the leading strand of the genome?

Genes in the (+) strand are black and genes in the (-)strand are red. The gene distribution in E. coli genome is somewhat expected: transcribed regions would tend to alternate with non transcribed ...
1
vote
2answers
170 views

Why do insects avoid being on their back?

I have noticed that when insects are placed on their backs, they tend to turn themselves over quickly or else appear to be in distress. Is there a physiologic, anatomic, or adaptive reason why supine ...
1
vote
0answers
42 views

Why do restriction-modification systems work?

Some RM systems (restriction-modification systems) are plasmid-borne and are transferred through bacterial conjugation. As you all know, there are two genes in an RM system, the gene that codes for ...
8
votes
1answer
123 views

Genotype to phenotype map and the G-matrix

Suppose I have a genotype-phenotype map defined by the matrix $\mathbf{Z}$:         The scalars $G,P$ represent the number of genotypes and traits, respectively. ...
1
vote
0answers
258 views

Reason for different color perception in left/right eyes?

What could be the reason for a difference in color perception between the two eyes of an adult individual without any known eye conditions? In particular, a difference in the perceived color ...
11
votes
3answers
587 views

Do other animals have different blood types?

Humans have the ABO and Rhesus blood typing systems. I have two questions about it: Why have we evolved these blood types? Do other animals have different blood types as well?
2
votes
1answer
54 views

Why is an increase in the amount of oxygen in the atmosphere favorable for life?

I have followed the David Attenborough series on 'First life' and heard, that an increase in the amount of oxygen in the atmosphere, as it took place just before the Cambrium, is generally favorable ...
4
votes
1answer
342 views

What do trans-fats do when in human body?

Trans fats cause health problems, especially to the heart. https://en.wikipedia.org/wiki/Trans_fat#Health_risks My guess is that all effects happen because trans-fats are inherently toxic as the ...
8
votes
2answers
561 views

Reasons why living fossils exist?

A living fossil is a living species (or clade) that appears to be similar to another species otherwise known only from fossils, typically with no close living relatives. A living fossil is ...
2
votes
0answers
57 views

What is NK-cell compartments?

with respect to the paper: Adaptive reconfiguration of the human NK-cell compartment in response to cytomegalovirus: A different perspective of the host-pathogen interaction What is meant by ...
3
votes
2answers
200 views

What proves that speciation is a pairwise process? [duplicate]

I have been asked this questions by many biology students and even non-biologist without a pretty straightforward answer to give. We are quite accustomed to phylogenetic trees where a common ancestor ...
1
vote
0answers
65 views

Why is amyloplast produced by some plant cells but not other cells?

For example I know it is produced in Potato's and fruits and its purpose is to synthesize glucose in to starch through polymerization. But why is it only present in some cells? Is it only present in ...
5
votes
1answer
75 views

How does de-myelination occur in multiple sclerosis?

From what I understand, only the oligodendrocytes are affected in multiple sclerosis, and they are attacked by T cells which cross the blood-brain barrier. This leads me to two questions: How is the ...
3
votes
2answers
46 views

enhancers in cell-type-specific signatures

I was reading an article in nature : Epigenomics: Roadmap for regulation and was confused by the definition or/and interpretation of enhancers. Enhancers are activated through interactions with ...
6
votes
3answers
265 views

Proteins folding

Some of us are involved in the folding@home project, spending time, money and resources. I would like to know an answer to two main questions: how do we know we fold it right? I mean these models ...
2
votes
1answer
82 views

Protein PTM site prediction

Is there any in silico analysis method to predict post-translational modification sites on a given protein?
2
votes
0answers
55 views

How do parrots stabilize their field of view without moving their necks while walking?

Based on my search online, I have found some theories which try to validate the activity of some birds (like pigeons) which involves moving their heads and neck while walking. These theories include - ...
1
vote
0answers
38 views

Which data format for mRNA expression matrix is necessary to run pathway analysis with Paradigm?

I am running Paradigm on a matrix of mRNA expression. I read Vaske, Charles J., et al. "Inference of patient-specific pathway activities from multi-dimensional cancer genomics data using ...
1
vote
0answers
22 views

Can medications or drugs damage oocytes? [closed]

Some drugs are teratogens, but can any drugs cause DNA damage to oocytes before ovulation or conception (eg chemotherapy drugs)?
8
votes
1answer
225 views

What is the mechanism behind tinnitus?

I seem to have come across two contrasting explanations for tinnitus induced by loud noises- i.e. damage to the hair cells in the cochlea. On the one hand, I have read that damage to the hair cells ...
2
votes
2answers
116 views

Can all biological processes be understood as computations and studied as such? [closed]

Can we understand a cell as an organic computational device? In that case the whole organism can be considered an ensemble of a large number of interacting computational devices? If this is the ...
1
vote
1answer
52 views

Mitochondria variability per tissue in humans?

I would like to know the distribution of mitochondrial content per tissue type in humans. I understand the simple metric that energetically active or energy requiring tissues will have more ...
3
votes
1answer
420 views

Retina Transplant Difficulties

Why is retina transplant not as easy as the normal eye donation and transplant (I think the latter involves the cornea ) ? This says that a new method has come up but why isnt the process similar and ...
4
votes
2answers
134 views

Name two reasons why it is impossible to determine a gene's nucleotide sequence from the amino acid sequence of the polypeptide

I can only think of one reason, which is because different codons can specify the same amino acids. However I am having trouble thinking of another reason.
2
votes
1answer
40 views

MTHFR recessive alleles and B-vitamins

I know that being heterozygous or homozygous recessive for the MTHFR gene prevents that person from being able to process and use folate and B-12. It causes an unhealthy level of homocysteine to ...
5
votes
2answers
217 views

The meaning of RNA-seq data

many papers I read mentioned "RNA-seq data". While searching for the meaning of this word, I could not find any layman's definition. As far as I understand, RNA-seq data is the complete RNA ...
2
votes
2answers
42 views

Possible to remove accumulated haze on fluorescence interference filters?

I have a few different fluorescent microscopes, the two that use Mercury lamps are older than 7 years. I notice on those that the thin film filters in the filter cubes (green, red, blue) have ...
3
votes
1answer
145 views

Divalent cation binding to calmodulin

I have carried out a native PAGE with 4 reaction mixtures. To each I had added an equal volume of EDTA (1 µl/1mM) to sequester any divalent ions and an equal volume of calmodulin (5 µl/0.5 mg/ml). I ...
3
votes
2answers
210 views

What is the minimum eye?

What is the minimum eye which confers some evolutionary advantage? By minimum I mean anything less than this has no advantage whatsoever and therefore is not favored by natural selection. By eye, I ...
4
votes
1answer
2k views

Why does cucumber skin kill ants?

I recently read that cucumber skin is an effective repellent for some ants: Set out cucumber peels or slices in the kitchen or at the ants' point of entry. Many ants have a natural aversion to ...
1
vote
1answer
43 views

Two mice heterozygote and black are reproduced. Find the probability of getting the filium dark and heterozygote [closed]

Well, here's what I did: P: Aa*Aa F1: 1/4 AA, 1/2 Aa, 1/4 aa, SO the answer is 1/2, but out teacher did this: AA(1) Aa(2) aa(1) and she said we divide the number of filium for the phenotypes ...

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