Renal Replacement Therapy (RRT) Overview. Overview of RRT. Renal replacement therapy (RRT) is required when the kidneys are functioning at less than 10â15 percent. Dialysis. People with advanced chronic renal failure (CRF), kidney failure, who have progressed to end-stage renal disease (ESRD) usually require dialysis.
Rods are maximally sensitive to wavelengths near 500 nm, and play little, if any, role in colour vision. In brighter light, such as daylight, vision is photopic: light is detected by cone cells which are responsible for colour vision.
Pine cones are the reproductive organs of pine trees. The cones are either male or female. Most pine tree species have both sexes of cones on each tree. The male cones produce pollen and the female cones produce ovules.The pollen and ovules must come into contact to fertilize and produce the next generation of pine trees.he cones are either male or female. Most pine tree species have both sexes of cones on each tree. The male cones produce pollen and the female cones produce ovules.