: 3) What is fold purification? A) Specific activity of purified fraction/relative activity of purified fraction B) Specific activity of crude sample/specific activity of purified fraction C) Specific activity of purified fraction/specific activity of crude sample D) Relative activity of purified fraction/specific activity of purified sample 4) Too much of high temperature, causes too much vibration within the enzyme, thus disrupting its 3D structure (True/False) 5) At optimal pH, the enzyme pH is not maximal (True/False)
The Correct Answer and Explanation is :
Let’s go through each question one by one.
3) What is fold purification?
Correct answer: C) Specific activity of purified fraction / Specific activity of crude sample
Explanation:
Fold purification is a measure of how much an enzyme or protein sample has been purified relative to the initial crude extract. It is calculated by comparing the specific activity of the purified fraction to the specific activity of the crude sample. The specific activity refers to the amount of substrate converted per unit of protein. By comparing these values, you can quantify how much more pure the enzyme is after the purification process.
Mathematically:
[
\text{Fold purification} = \frac{\text{Specific activity of purified fraction}}{\text{Specific activity of crude sample}}
]
A fold purification value of 1 means there has been no purification, while higher values indicate greater purification. For example, if the specific activity of the purified fraction is 10 times higher than the crude sample, the fold purification is 10. This is important in biochemistry to determine the efficiency and effectiveness of the purification methods.
4) Too much of high temperature causes too much vibration within the enzyme, thus disrupting its 3D structure. (True/False)
Correct answer: True
Explanation:
Enzymes are proteins, and their function is dependent on their 3D structure, which is stabilized by various bonds and interactions such as hydrogen bonds, ionic bonds, and hydrophobic interactions. When the temperature is too high, the kinetic energy of the molecules increases, causing more vibration within the enzyme. This excessive vibration can break the weak bonds that hold the enzyme in its specific shape, leading to denaturation.
Denaturation refers to the process where the enzyme loses its functional structure, and as a result, it becomes inactive. This is why enzymes have optimal temperature ranges where they work best. Beyond this range, especially at high temperatures, the enzyme’s active site may change shape, preventing the enzyme from binding to its substrate, thus reducing or stopping its catalytic activity.
5) At optimal pH, the enzyme pH is not maximal. (True/False)
Correct answer: False
Explanation:
Enzymes have an optimal pH range in which their activity is maximal. At this pH, the enzyme’s active site is in the best possible shape for binding to the substrate, and the enzyme can catalyze reactions at its highest rate.
When the pH is too low or too high, the enzyme’s 3D structure can be disrupted, particularly at the active site, which can reduce or stop the enzyme’s activity. For example, in the case of digestive enzymes, pepsin has an optimal pH of around 2, while enzymes like amylase have an optimal pH closer to 7.
Thus, at optimal pH, the enzyme’s activity is at its maximum, not at a suboptimal level, making the statement false.