Search found 27 matches

by dae
Mon May 20, 2013 6:10 pm
Forum: Human Biology
Topic: Late night metabolic second wind
Replies: 0
Views: 2607

Late night metabolic second wind

A question I've never gotten a fully satisfying answer to: what mechanisms are kicking in to give me a 'second wind' late at night? Basically I go through my day (usually up around 7, in lab by 9) and am fairly exhausted by 8 or 9pm every night. But by 11pm/12am, my energy picks up again and I can e...
by dae
Thu Oct 15, 2009 4:05 pm
Forum: Botany Discussion
Topic: Does all photosynthesis use CO2?
Replies: 3
Views: 3046

Does all photosynthesis use CO2?

I can't find an easy answer to this online, so does all photosynthesizing life use carbon dioxide (or carbonic acid/bicarbonate/carbonate) as the source of carbon?

Thanks!
by dae
Thu Oct 15, 2009 2:08 am
Forum: General Discussion
Topic: Nit-picking dilutions
Replies: 5
Views: 2360

Re: Nit-picking dilutions

Thanks, I corrected the 5X above :oops: I realize that for a 1X buffer of TAE this is silly nuance but what I'm asking is if, for some reason, accuracy is paramount, what is the definitional way to make a working solution from a 50X stock?

Thanks for your patience :-)
by dae
Thu Oct 15, 2009 1:20 am
Forum: General Discussion
Topic: Nit-picking dilutions
Replies: 5
Views: 2360

Re: Nit-picking dilutions

Thanks, I guess I should clarify: is there a type of dilution that is defined by the addition of specific amounts rather than final volume?
by dae
Wed Oct 14, 2009 9:15 pm
Forum: General Discussion
Topic: Nit-picking dilutions
Replies: 5
Views: 2360

Nit-picking dilutions

This is not important for most biological applications but... I know that for making most simple solutions you dilute things up to a desired volume with solvent. E.g. a 20% w/v solution of glycine is 20g glycine with diH2O added until the final volume is 100mL. Same story with molarities. But is it ...
by dae
Sat Oct 03, 2009 2:26 pm
Forum: Molecular Biology
Topic: Biochemical Buffers Confusion
Replies: 3
Views: 3125

Re:

JackBean wrote:Are you adding the buffer to solution or solution to the buffer?


I'm adding sodium bicarbonate as a solid to diH20. Thanks, I should have specified that.
by dae
Sat Oct 03, 2009 7:22 am
Forum: Molecular Biology
Topic: Biochemical Buffers Confusion
Replies: 3
Views: 3125

Biochemical Buffers Confusion

Is it correct to to think that a buffer will always shift a solution toward the buffer's pKa? For instance, if I have an aqueous solution of pH 3 and I add acetic acid (pKa = 4.76), the pH of the solution should rise, right? But I sure I'm missing something because by that logic adding neural water ...
by dae
Wed Mar 18, 2009 5:11 am
Forum: Molecular Biology
Topic: Why does DNA fluoresce under UV light?
Replies: 2
Views: 5562

Why does DNA fluoresce under UV light?

I read that it is the DNA in body fluids that make them fluoresce under UV light but I'm not sure why. If that's true, why do we need to add ethidium bromide to visualize DNA gels, wouldn't the DNA be visible by itself? Is it just a mater of intensity? I also heard that body fluids have to be dry in...
by dae
Wed Mar 18, 2009 5:04 am
Forum: Molecular Biology
Topic: DNA extraction
Replies: 1
Views: 2926

DNA extraction

My class did a simple DNA extraction from cheek epithelial cells. The protocol involved lysing the cells with 4% detergent, 1% NaCl and vortexing, centrifuging at 11krpm to form a cell pellet, and adding cold ethanol to the supernatant to precipitate the DNA. Afterwards we were asked the following t...
by dae
Tue Mar 10, 2009 4:07 am
Forum: Cell Biology
Topic: Basic meiosis question
Replies: 3
Views: 2432

Re: Basic meiosis question

Thanks! that makes way more sense :-)
by dae
Mon Mar 09, 2009 8:48 pm
Forum: Cell Biology
Topic: Basic meiosis question
Replies: 3
Views: 2432

Basic meiosis question

In metaphase I can both of the chromatids of a double chromosome crossover? In textbooks the tetrad complex is always shown laid flat (it looks like XX ) so it makes since that only one chromatid from each double chromosome would be able to recombine in that geometry. But if this is a simplification...
by dae
Sat Aug 09, 2008 9:37 pm
Forum: Botany Discussion
Topic: carbon fixation of conifers
Replies: 2
Views: 4527

carbon fixation of conifers

What carbon fixation pathway do conifers use? Is it CAM? I haven't found an explicit answer yet.

Thanks!