Final answer:
The ascending limb of the loop of Henle is impermeable to water and actively transports sodium, potassium, and chloride ions out of the filtrate through ion channels.
Step-by-step explanation:
The ascending limb of the loop of Henle is impermeable to water. It actively transports sodium, potassium, and chloride ions out of the filtrate through ion channels present in the cell membrane. This helps maintain a high osmolarity in the renal medulla.