GLUT2 have a lower affinity for glucose and is essential for the liver and the pancreas to regulate the blood glucose level. With a lower affinity transporter, glucose will not be taken up immediately by the liver/pancreas while reserving for the high glucose demanding organs (e.g brain, neurons, red blood cells). Therefore, if one were to inherit such disease, extreme hypoglycemia may occur.   

GLUT1 and GLUT3 have the highest affinity for glucose. The Michaelis constant,  is the concentration of the substrate required to reach . The lower the , the higher the affinity is for the substrate.  

The enzyme in this question is said to be saturated with substrate. That means that at any given moment, all of the enzyme in solution is bound to a substrate so that adding more substrate will have no effect. This is referred to as the maximal velocity because the enzymes are working as fast as possible and will not respond to the addition of more substrate. By adding more enzyme, you a providing more active site to bind to more substrate molecules, effectively increasing the velocity of the overall reaction.

In enzyme kinetics,  is the concentration of substrate which allows the enzyme to reach  (maximum reaction velocity). A small  indicates that only a small amount of substrate is needed for the enzyme to become saturated and thus for the reaction to reach maximum velocity. This also indicates that the enzyme and substrate have high affinity for one another. A large  indicates that a large amount of substrate is needed for the enzyme to become saturated and thus for the reaction to reach maximum velocity.

The Michaelis constant, , is a frequently used value in enzyme kinetics used to essentially describe how much substrate is needed to speed up a reaction. More specifically, it is the substrate concentration required to get a reaction to half of its  (the correct answer is ). The  itself is given as a specific substrate concentration, and in order to find it, one would draw a straight line across on an enzyme kinetics graph at  until reaching the curve. The substrate concentration that is found at that point is the .

 can be defined as  or as _.

However, on a Lineweaver-Burk plot, the Y-intercept actually represents . It is the X-intercept that  can be derived from. The X-intercept is equivalent to .

Competitive inhibitors will block the active site of the enzyme. The presence of the competitive inhibitor increases the amount of substrate required to get the enzyme to half of its maximum velocity. As a result, the  of the enzyme will increase. Note that a competitive inhibitor will not affect the maximum velocity of the enzyme.