83 Answered Questions for the topic molecular biology

Molecular Biology Biochemistry Gel Electrophoresis


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... more
Molecular Biology Microbiology Cell Biology


True or False. The gene is the basic unit of genetic information.


How do antioxidants affect human metabolism?

I'd like to know how antioxidants affect human metabolism and which ones are essential for metabolic processes.
Molecular Biology Microbiology Cell Biology


How do RNA cells differ from DNA?

Molecular Biology Biochemistry Respiration


How does the body switch between aerobic and anaerobic respiration?

Lets take the case of a person doing heavy exercise. Aerobic respiration is taking place, but oxygen is about to be finished up. Glycolysis occurs, Krebs cycle finishes. Now NADH and... more
Molecular Biology Biochemistry Botany Photosynthesis


What is the relationship between the light and dark reactions of photosynthesis?

My main concern is why are the dark reactions (those that produce hexose) needed? As far as I understand, the sole purpose of photosynthesis is to synthesize carbohydrates, which are only used for... more
Molecular Biology Biology Genetics Cell Biology


A photosynthesizing mouse?

N. Shubin's *Your Inner Fish* makes the point several times that there is a lot of functional similarity between some seemingly remote gene cousins. If that needed reinforcing we have the... more
Molecular Biology Biochemistry Zoology Human Biology


Why do we have no enzyme to digest cellulose?

As we know, cellulose is the most abundant polysaccharide in nature. Why don't we have an enzyme to digest cellulose?
Molecular Biology Biology Biochemistry Genetics


Is HSV-vector-mediated miRNA expression in dorsal root ganglia stable?

My question is on the following article: "*[Reduction of voltage gated sodium channel protein in DRG by vector mediated miRNA reduces pain in rats with painful diabetic... more
Molecular Biology Genetics Rna


Is there a double helix RNA?

I wonder what is its function and if it can be the genetic material for a living organism. If not, why?
Molecular Biology Biochemistry Cell Membrane


How do ion channels transport only specific ions?

Ion channels, such as $Na^+$ channels and $K^+$ channels, are higly specific for ion permeability. But how do these channels achieve and maintain this specificity? Like how does a $K^+$ channel... more


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... more
Molecular Biology Biology Biochemistry Cell Biology


In mitochondria, what is the mechanism by which electrons are transferred between different cytochromes?

And how is the energy gained from the lowering of the "energy level" of the electron used to generate the chemiosmotic gradient?


Does any molecule other than DNA have a double-helical structure?

DNA is known to have a double-helical structure. Do any other molecules have this structure?
Molecular Biology Biochemistry Ribosome


Why do 60S & 40S ribosomal subunits make an 80S ribosome (not 100S)?

Why do 60S & 40S subunits make an 80S (not 100S) ribosome and, similarly, 50S & 30S make 70S? 60+40 is not equal to 80, nor is 50+30 equal to 70, so why are the subunits of the 80S and 70S... more
Molecular Biology Biology Biochemistry Photosynthesis


Photosynthesis: What Powers the Splitting of Water?

The splitting of water is an endergonic (non-spontaneous) reaction, and thus would require energy (chemical work to be done) in order to happen. In Photosystem II, an enzyme catalyzes this... more
Molecular Biology Biology Cell Biology Proteins


What happens to the precursor protein's signal sequence after it is cleaved?

Where does this signal sequence "go" after it has been cleaved by signal peptidase and what is its next function?
Molecular Biology Biochemistry Biophysics


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** ... more
Molecular Biology Biology Biochemistry Cell Membrane


What is the purpose of the outer mitochondrial membrane?

The purpose of mitochondria is to generate ATP, utilising a chemiosmotic gradient across the inner mitochondrial membrane. Protons are pumped out of the mitochondria into the intermembrane space,... more

Still looking for help? Get the right answer, fast.

Ask a question for free

Get a free answer to a quick problem.
Most questions answered within 4 hours.


Find an Online Tutor Now

Choose an expert and meet online. No packages or subscriptions, pay only for the time you need.