On Fig. 5.1, add label lines and letters to identify the kidney regions where the following are found: L - loop of Henlé; D - distal convoluted tubule; P - podocyte cells.
In a cold environment, people pass urine more often. This is called cold diuresis. When it is cold, homeostatic control limits heat loss as much as possible. Blood is redirected away from the skin so that a larger proportion of blood flows around the main body organs, including the kidney. Suggest and explain why cold diuresis occurs.
The water potential of the blood is kept at a constant level by a process called negative feedback. With reference to the maintenance of the water potential of the blood, explain what is meant by negative feedback.
ADH changes the number of water channel proteins, aquaporins, in the cell surface membranes of the cells of the distal convoluted tubule. State what happens to the water potential and volume of the urine if cells in the distal convoluted tubule have more aquaporins in their cell surface membranes. water potential ............................................................. volume of urine .............................................................