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This section includes 9 Mcqs, each offering curated multiple-choice questions to sharpen your Chemistry knowledge and support exam preparation. Choose a topic below to get started.
1. |
Antagonists do not allow the transfer of message through receptors. |
A. | True |
B. | False |
Answer» B. False | |
2. |
The drugs that are used when there is a lack of natural chemical messenger is called ______ |
A. | antagonists |
B. | agonists |
C. | analgesics |
D. | narcotics |
Answer» C. analgesics | |
3. |
Which of the following is not a reason for the selectivity of receptors towards messengers? |
A. | Shape of binding site |
B. | Structure |
C. | Amino acid composition |
D. | Location in the membrane |
Answer» E. | |
4. |
Which of the following is incorrect regarding receptors? |
A. | They have constant shape |
B. | They are proteins |
C. | The shape of receptors binding site changes to fit the messenger |
D. | They are present in the cell membrane |
Answer» B. They are proteins | |
5. |
If the bond between the enzyme and inhibiting drug is very strong, which of the following takes place? |
A. | The active site slowly regains its original shape |
B. | The enzyme develops a new active site |
C. | The enzyme is blocked temporarily |
D. | The body synthesizes a new enzyme |
Answer» E. | |
6. |
A certain compound occupied a site Y of an enzyme near to the active site. This immediately resulted in the change of shape of the active site. Y is called a/an ______ |
A. | inactive site |
B. | binding site |
C. | non-competitive site |
D. | allosteric site |
Answer» E. | |
7. |
A certain compound X occupied a site of an enzyme exactly opposite to that of the active site. This immediately resulted in the change of shape of the active site. X is called a ______ |
A. | competitive inhibitor |
B. | non-competitive inhibitor |
C. | competitive messenger |
D. | receptor |
Answer» C. competitive messenger | |
8. |
All drugs block enzyme activity by occupying the active site before the substrate. |
A. | True |
B. | False |
Answer» C. | |
9. |
Drugs that block the binding site of an enzyme form a substrate are called ______ |
A. | inhibitors |
B. | poisons |
C. | messengers |
D. | receptors |
Answer» B. poisons | |