Who coined the term $zymase$ for enzymes in yeast?

The following graph shows the effect of substrate concentration on enzyme activity. What does the $Y$-axis represent?

Which enzyme catalyzes the breaking of bonds without the use of water or oxidation?

Which of the following statements is correct?

Regarding the catalytic cycle of an enzyme action,select the correct sequential steps:
$A$. Substrate-enzyme complex formation.
$B$. Free enzyme ready to bind with another substrate.
$C$. Release of products.
$D$. Chemical bonds of the substrate broken.
$E$. Substrate binding to active site.
Choose the correct answer from the options given below:

Which enzyme catalyzes the reaction shown below?
Lactose $\xrightarrow{\text{Hydrolysis}}$ Glucose + Galactose