444 Answered Questions for the topic biochemistry
What are the sources of molecular hydrogen in human breath?
In the BBC News article [CES 2019: Tech preview of the expo's hottest new gadgets](https://www.bbc.com/news/technology-46715334) there is a new product that one can use to measure the hydrogen in... more
Why is it often the case that an enzyme is favorable only towards one direction of a reaction and not both directions?
In class when we're studying enzymes like amylase or protease it only works well when you're using it to break down compounds like polysaccharides. I'm just curious but why is it not possible for... more
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
Is there an enzyme for the transformation of the hydroxyl group?
I would like to know, is there any enzyme which does the transformation of hydroxyl group to any other functional group using the enzyme. The substrate is aromatic hydroxyl group. Product should... more
In biosynthesis of cysteine and methionine, where does the sulfur come from?
Methionine and Cysteine are the two amino acids containing sulfur. [According to wikipedia, cysteine](https://en.wikipedia.org/wiki/Cysteine) is built from methionine. However, the wikipedia also... more
Why does a "cascade" of events happen during signal transduction?
I've been watching some videos on signal transduction and it says that because there are enzymes being activated by the signal, then there is a "cascade" which happens afterwards...I don't... more
How do centrioles auto-locate to opposite sides of cell during mitosis?
I realize that centrioles are made of 9 triplets of microtubulin wound together with a hollow core, and that they are responsible for the configuration of the spindle during mitosis. The spindle... more
What is the difference between "Bisphosphate" and "Diphosphate" in biochemistry?
I have often found bisphosphate compounds ( e.g. RuBP, RuBisCO, 2,3-BPGA etc.) and diphosphate compounds (e.g. ADP, GDP etc.) in biochemistry. They are commonly seen and are important compounds in... more
Simple diffusion of lipid-soluble molecules through phospholipid bilayer -- does anything get "stuck" in transit?
It's a pretty elementary concept, and when I first learned of it I don't think I had the foundations to even think of such a question, but I found myself the other day thinking about the... more
What do sphingolipids do in humans?
I want to know the significance of sphingolipids in human. I have learnt that sphingomyelin is the most significant type of sphingolipid in human. Also that the sphingomyelin serves as a structural... more
Using ion-exchange chromatography to purify DNA from a cell extract - Is DNA more negatively charged then RNA?
When applying this method we have a glass or plastic column of resin which is positively charged. Then we pour cell extract into the column in order to capture the negatively charged particles... more
Significance of lipids in biological membranes...?
Membranes are specifically designed by lipids to maintain internal hydrophilic environment in narrow range.There are hydrophobic amino acids among naturally occurring 20 amino acids and as well as... more
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
Is ATP Synthase a channel or an enzymatic protein?
Today in a biology lecture about plasma membranes and functions of proteins, we learned about channel and enzymatic proteins along other kinds of proteins. ATP synthase is considered an enzyme that... more
Why are proteins always made in N to C direction??
Why are proteins always synthesized from the *N*-terminus to the *C*-terminus? Can there be any “reverse” peptide-bond formation to synthesize proteins in the *C*-terminal to the *N*-terminal... more
What is the biochemistry of love?
How is love induced between humans? (e.g. between mother and child,couples,etc)?Does the phenomenon of love exist in other mammals, too?
Role of calcium chloride during competent cell preparation?
I am aware of the fact that $CaCl_2$ settles down on the cell wall making it less negative may be by forming bond with Teichoic acid. Also due to the positive charge it attracts DNA (DNA is... more
How does water buffer a sudden drop in temperature?
A property of water is that it is slow to heat and cool. According to my biology book, some energy from an increase in temperature would spent breaking hydrogen bonds, so that temperature does not... more
How does hypochlorous acid inactivate viruses?
I was reading how bleach was used very widely as a disinfecting agent during the 2014 West Africa ebola outbreak and am interested in the mechanisms with which hypochlorous acid inactivates... more
Why does the ring finger not move independently?
Why is it that we need to move little finger in order to move ring finger with it? For example, put your palm on a table and fold your middle finger inside. You won't be able to move your ring... more
Are Gram negative bacteria classified as such because of their negative membrane potential?
Does the membrane potential usually quoted for Gram negative bacteria (*e.g.*, *E. coli*) refer to the potential across both membranes? - If yes, then does the potential fall more over the inner or... more