Which part of the renal tubule is lined with cuboidal epithelial cells bordered by dense microvilli?

Surrounded by microtubules, located near the nucleus. (don't try to google it) (give answer only if u know)

What was dr. willem johan kolff’s first step in using the scientific process to invent the hemodialysis machine? he built the machine and tried it with various patients, collecting data about its effectiveness. when a patient’s kidneys failed, he wondered if it would be possible to perform kidney functions with an external machine. he researched and collected data about numerous patients who exhibited symptoms of kidney failure. he drew conclusions from studies of various symptoms of kidney failure, and drew a design for the ideal external blood-processing machine.

With regard to enzymes, key is to lock as a) substrate is to activation energy eliminate b) product is to substrate. c) enzyme is to active site. d) substrate is to active site.