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.
The Fruits of Conifers. Conifers have two types of cones: pollen cones and seed cones. Depending on the tree species, you may find both types of cones on the same tree or on different trees. When seed and pollen cones are found on different trees, the species is called dioecious.