What is a protein that acts as a catalyst to bring about a specific biochemical reaction, while its structure and functions do not change?

1.1.3 A protein that acts as a catalyst to bring about a specific biochemical reaction, while its structure and functions do not change is an enzyme. Enzymes speed up biochemical reactions without being consumed in the process.

• D) Enzyme

1.1.4 A regulatory substance produced and secreted directly into the blood to stimulate specific cells or tissues into action is a hormone. Hormones act as chemical messengers in the body.

• C) Hormone

1.1.5 An energy reserve that is produced from metabolism of glucose by the liver is glycogen. The liver converts excess glucose into glycogen for storage.

• C) Glycogen

1.1.6 The final usable form of energy inside the cell is adenosine triphosphate (ATP). Cells break down ATP to release energy for various cellular activities.

• Adenosine triphosphate (ATP)