September 27, 2018

Fatty acids are types of lipids that can be found in many different roles in our body including energy storage. Fatty acids consist of hydrocarbon chain with carboxylic acid at the end. Thus fatty acids are called amphiphilic (they have both hydrophobic and hydrophilic parts). Fatty acids can be saturated (all single bonds) or unsaturated (have double bonds).

September 22, 2018

In organic chemistry students will learn both Jones (CrO3/ aq H2SO4) and PCC reagents and will need to know how to differentiate between the two. Both reagents oxidize alcohols. Only secondary and primary alcohols can be oxidized, since oxidizing tertiary alcohol will lead to a carbon with five bonds which is impossible. Both Jones reagent and PCC turn a secondary alcohol into a ketone, going from C-OH to C=O. The diffe...

September 18, 2018

What does bond order mean? Bond order is directly proportional to the strength of the bond. Thus, the higher the bond order the strong the bond and the more energy it takes to break it. Bond order is also indirectly proportional to the length of the bond. The higher the bond order, the shorter the bond is.

September 16, 2018

Prion is a misfolded version (wrong secondary and tertiary structure) of prion protein that is transformed to an infectious particle that leads to disease. How does prion come about? Generally, when proteins get misfolded in our body, they are either sent to be repaired or get degraded by protease (an enzyme that breaks down proteins). Prions, however, are resistant to the protease and remain misfolded and undegraded. T...

September 14, 2018

Enzymes are biological catalysts that help to speed up the rate of reactions. All enzymes have two very important factors, Km and Vmax. V max is the maximum speed of the enzyme. Km is the concentration of substrate needed for the enzyme to work at half of its maximum speed. The lower the km, the better the enzyme is and the higher it's affinity for substrate is.

Inhibitors are molecules that inhibit or diminish the produ...

September 13, 2018

ATCase exhibits cooperatively, which means that as one substrate molecule binds the active sites become more and more likely to bind more substrate molecules. ATCase, therefore, can be in the  R- relaxed(as the substrate binds, the structure changes so that affinity for the substrate increases) and T - tense state (without the substrate --> low catalytic activity).  Allosteric effectors of ATCase are : CTP and ATP. All...

September 12, 2018

DeltaG tells us whether a reaction is spontaneous or not. If delta G is negative, the reaction is spontaneous, and if delta G is positive, the reaction is not spontaneous. There is a relationship between deltaG and equilibrium constant, K. It is given by the formula deltaG=-RTlnK, where R is the gas constant (8.314J K−1 mol−1), T is the temperature in Kelvin, and K is the equilibrium constant.

September 10, 2018

If the question is asking for a pH, the first thing we need to recognize is whether we are dealing with acid or base and whether it is strong or weak?

Strong acids are the following: HCl - hydrochloric acid, HNO3 - nitric acid, H2SO4 - sulfuric acid, HBr - hydrobromic acid,HI - hydroiodic acid, HClO4 - perchloric acid, HClO3 - chloric acid. If an acid is not one of these, it is a weak acid. Moreover, if ka value is given...

September 6, 2018

First ionization energy is the amount of energy needed to take first electron from an atom. The trend for ionization energy is that it increases from the bottom to the top and from the left to the right.

Why? The bigger an atom's radius is, the further away outer electrons from the pulling of the nucleus are and the less energy is needed to take them away. Thus, ionization energy trend is opposite of that of radius. 

Ther...

September 2, 2018

Isoelectric point or pI is a ph at which an amino acid or protein has a net charge of zero.

Biochemistry classes always ask students to find pI for an amino acid and here is the short and sweet way to do it.

For neutral amino acids, two pka's will be given, and pI = (pKa1 + pKa2)/2

For acidic amino acids ( aspartic acid and glutamic acid), we average out the two lowest pka, so we do not take into account the amino terminal...

Please reload

Featured Posts
Recent Posts
Please reload

Archive