Lactose Transporter How Does it Work

The video explains the lactose transporter, a type of secondary active transport, which requires a proton pump to function. The pump creates a proton concentration gradient, enabling lactose to be transported into the cell. The mechanism involves protonation of a carboxyl group, leading to a conformational change in the transporter protein. Inhibition of the proton pump disrupts this process. The video concludes with a preview of primary active transport.

What is the role of the proton pump in the lactose transporter mechanism?

• To directly transport lactose into the cell

• To create a high concentration of protons outside the cell

• To synthesize ATP for energy

• To break down lactose into simpler sugars

How does the lactose transporter utilize the proton gradient?

• By moving lactose and protons in opposite directions

• By using the energy from ATP hydrolysis

• By moving lactose and protons in the same direction

• By converting lactose into glucose

What happens to the carboxyl group during lactose transport?

• It becomes deprotonated, allowing lactose to bind

• It is converted into a hydroxyl group

• It becomes protonated, allowing lactose to bind

• It is removed from the protein

What is the effect of protein conformation change in lactose transport?

• It allows lactose to move out of the protein into the cell

• It prevents lactose from entering the cell

• It causes the protein to degrade

• It stops the transport of protons

What would happen if the proton pump is inhibited?

• Lactose transport would continue unaffected

• Proton concentration outside the cell would increase

• Lactose transport would be inhibited

• Proton concentration inside the cell would decrease

Why is lactose transport considered secondary active transport?

• It does not require any energy input

• It relies on a concentration gradient created by another enzyme

• It directly uses ATP to transport lactose

• It uses light energy to transport lactose

What is the primary fuel source for the proton pump in this mechanism?

• ATP

• Glucose

• An unspecified fuel source

• Lactose