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.
Rod cells are far more numerous than cone cell. Cones cells are far fewer than rod cells. Usually located around the periphery of retina. Usually located in the centre of retina. All rod cells are alike, and do not give colour vision. Cones are of three types: blue, green and red, and give colour vision.
Determine the type of scales. Female cones have two types of scales: bract and seed or ovuliferous scales. Bract scales are modified leaves and develop first, earlier on in spring or summer; seed scales develop later and cover the bract scales to protect the ovules, which will develop into pine seeds.