Reabsorption of Glucose via Carrier Proteins

10/27/2020 PhysioEx Exercise 9 Activity 5 PhysioEx Lab Report Exercise 9: Renal System Physiology Activity 5: Reabsorption of Glucose via Carrier Proteins Name: Date: 27 October 2020 Pre-lab Quiz Results You scored 75% by answering 3 out of 4 questions correctly. 1 Renal processing of plasma glucose does not normally include You correctly answered: secretion. 2 How does antidiuretic hormone (ADH) affect the renal processing of plasma glucose? Your answer: ADH increases the amount of plasma glucose that is filtered out of the glomerular capillaries. Correct answer: ADH has no direct effects on renal processing of plasma glucose. 3 Glucose reabsorption in the nephron includes You correctly answered: secondary active transport along the apical membrane of proximal tubule cells. 4 Because carrier proteins are required to move glucose from the lumen of the nephron into the interstitial spaces, which of the following statements is false ? You correctly answered: The number of glucose carriers in a nephron can be altered as needed by the body. Experiment Results Predict Question 1 Predict Question: What will happen to the glucose concentration in the urinary bladder as glucose carriers are added to the proximal tubule? Your answer: The glucose concentration will increase. Stop & Think Questions 1 Why is the glucose concentration the same in both Bowman's capsule and the urinary bladder? i 1/3 10/27/2020 PhysioEx Exercise 9 Activity 5 You correctly answered: Glucose cannot be reabsorbed in the absence of carriers. 2 Is a transport maximum reached in these experiments? You correctly answered: yes. Experiment Data Glucose Conc. Capsule Glucose Conc. Distal Glucose Conc. Bladder Total Glucose Carriers Conc. Grad. 6.00 6.00 6.00 0 1200 6.00 4.29 4.29 100 1200 6.00 2.57 2.57 200 1200 6.00 0.86 0.86 300 1200 6.00 0.00 0.00 400 1200 Post-lab Quiz Results You scored 100% by answering 3 out of 3 questions correctly. 1 Glucose carrier proteins are located in which region of the nephron? You correctly answered: the proximal convoluted tubule. 2 If the concentration of glucose in the filtrate exceeds the transport capacity of the carrier proteins, then You correctly answered: a transport maximum has been reached. 3 Why does glucose appear in the urine of untreated diabetic patients? You correctly answered: An excessive amount of glucose is present in their filtrate. Review Sheet Results 1 What happens to the concentration of glucose in the urinary bladder as the number of glucose carriers increases? Your answer: My prediction was wrong. The glucose concentration actually decreased in the urinary bladder as more glucose carriers were added. This is due to reabsorption. 2 What types of transport are utilized during glucose reabsorption and where do they occur? Your answer: i 2/3 10/27/2020 PhysioEx Exercise 9 Activity 5 Secondary active transport happens when the glucose is entering the apical membrane and facilitated diffusion happens when glucose is leaving through the basolateral membrane. 3 Why does the glucose concentration in the urinary bladder become zero in these experiments? Your answer: There are more available transport proteins than there is glucose. The transport proteins become filled up with glucose and the additional glucose is secreted in urine. 4 A person with type I diabetes cannot make insulin in the pancreas, and a person with untreated type II diabetes does not respond to the insulin that is made in the pancreas. In either case, why would you expect to find glucose in the person's urine? Your answer: Type 1 diabetes has an elevated level of glucose in the blood because the person cannot make insulin in the pancreas. This leads to an increased level of glucose in the filtration system and glucose transport proteins completely fill up, making the extra glucose being secreted in the urine. A person with diabetes type 2 does not respond to the insulin being made. It makes it's glucose in the system, increasing the levels of glucose making more glucose being secreted. i 3/3