Question

Many organisms can use carbohydrates other than glucose as a source of carbon and energy. For example, lactose is a disaccharide that is converted to the two monosaccharides glucose and galactose by the enzyme lactase. This reaction is shown below:

Answer 1

a) The reaction above is spontaneous from left to right.
Will the reaction from left to right occur to a significant degree in the absence of enzyme?

Yes
No
Cannot tell from the information given

Will the reaction from right to left occur to a significant degree in the absence of enzyme?

Yes
No
Cannot tell from the information given

b) Indicate whether each of the following statements are true or false:

Lactase provides the energy to make the reaction proceed faster.

True
False

Lactase reduces the free energy change for the reaction shown above.

True
False

c) Suppose you have a reaction where the initial rate of conversion of lactose into glucose and galactose is 1000 molecules per second. The reaction is repeated but the concentration of substrate is increased 10-fold while the concentration of enzyme remains the same. The initial rate of conversion of lactose into glucose and galactose in the new reaction will be…

Greater than 1000 per second
1000 per second
Less than 1000 per second
Cannot tell from the information given