Question

Explain in biochemical terms, the relationship between glucose and lactose in the body, and how many NADH are made after the cycle

Answer 1

Glucose, fructose, sucrose and lactose are the important carbohydrates and source of energy for our body. They all provide the same amount of the energy (4 kcal) per gram, but they qre processed and used differently in body. Glucose and fructose are monosaccharides (one sugar unit) and are building blocks of the sucrose, a disaccharide (2 monosacharides joined together by dehydration reaction). Lactose is a disaccharide formed from the glucose and galactose.

Glucose- The blood sugar (released after digestion of the food carbohydrates)- circulates in blood, to be used for the immediate energy, or if in the excess, to be stored as glycogen in liver as the energy reserve. The hormone insulin is secreted primarily in the response to elevated the blood concentrations of glucose, and the insulin is the key which facilitates the entry of glucose into the cells. Diabetics, who have the deficiency or lack of insulin in the body.

In other hand ,the Lactose the disachharide formed by the glucose and galactose, is found in the milk and is an important source of ready energy for infants which have breast milk. Lactose is broken down into glucose and the galactose by enzyme lactase, which reduces naturally in body with age. Some people have lactose intolerance and they cannot digest milk due to the lactase deficiency. They can also have curd, soy milk, paneer, cheese (which has less lactose).

The net gain of the high-energy compounds from one cycle is 3 NADH, 1 FADH₂, and 1 GTP, the GTP may subsequently be the used to produce ATP. Thus, the total yield from 1 glucose molecule (2 pyruvate molecules) is the 6 NADH, 2 FADH₂, and 2 ATP.