Tagged Questions

2
votes
2answers
81 views

Why do neurones use chemical signalling at synaptic junctions?

Problem. When a neurone fires, it sends an electrical signal that jumps down the axon via the nodes of Ranvier very rapidly. At a synaptic junction, chemical brownian diffusion signalling with ...
3
votes
1answer
37 views

What molecular processes are involved in pseudopodial extension?

I am curious as to the processes and mechanisms involved in the extension of pseudopodia in amoeba. How does the cell know and control the direction and extent of pseudopodia formation at a molecular ...
5
votes
1answer
186 views

Very high 260/230 absorbance ratio of an RNA sample

After my most recent RNA extraction, the RNA samples had very high 260/230 absorbance ratios, (ranging from 5 to 25). I've never gotten numbers like this and I know the ratio is supposed to be ~2 in ...
1
vote
0answers
42 views

Solid phase use in HIV rapid tests

I have another question in regards to my HIV test research. The rapid tests like Orasures Oraquick contains a strip of synthetic peptides that are used to represent proteins found in the envelope ...
7
votes
2answers
141 views

Bacterial cell lysis - what solution to use?

I am trying to determine how quickly detergents act on bacterial cells (cell lysis). I would like to compare some detergents at difference concentrations for bacteriolytic activity. I don’t care about ...
10
votes
1answer
72 views

When running a gel, what could cause a standard to run “faster” than usual?

We are running a gel on the products of a restriction digest to determine the size of an insert. We know the vector backbone size should be ~2.9kb; however, the standard appears to be running too ...
4
votes
2answers
183 views

DNA as an acid? [duplicate]

Possible Duplicate: Does DNA react in all of the ways most other acids do? Even if DNA is made up of nucleotide bases, it is said to be an acid. Why is this?
3
votes
3answers
74 views

Is DNA mutation locally energetically stabilizing the DNA molecule

I am no biologist, but as a physicist, a spontaneous mutation (seen as a chemical transformation) should lower the energy of the system, at least locally. So I wonder if any research has been done ...
7
votes
1answer
92 views

How Antioxidants affects Human Metabolism?

I'd like to know how antioxidants affects the human metabolism and which ones are essential for metabolism processes.
9
votes
2answers
1k views

Why is PEG important for efficient yeast transformation?

One way to do an yeast transformation is by using lithium acetate, a single-stranded carrier DNA, and PEG (1). I was wondering why is the polyethylene glycol important for the efficient ...
16
votes
1answer
343 views

ATP cost for gene expression

How would you estimate the number of ATPs required to transcribe, export and translate a single eukariotic protein?
17
votes
1answer
314 views

How, on a physical level, does ATP confer energy?

When ATP is used as the energy currency to make, say, reaction X + Y → Z happen, is what happens on a physical level down at the molecular scale that during the reaction ATP + H2O → ADP + Pi ...
10
votes
1answer
157 views

What is the functional and structural distinction between core (H2A, H2B, H3,H4) and linker(H1/H5) histones?

Many explanations of histone biochemistry isn't quite elucidating for the undergraduate student. How does histone structure (dimers, octomers) relate to their specific functions as core or linker ...
9
votes
4answers
166 views

How can I avoid digesting protein-bound DNA?

I'm interested in sequencing and analyzing the bound DNA, and minimizing the amount of unbound DNA that gets sequenced through digestion. When digesting protein-bound DNA, is all of the unbound DNA ...