11.3 The Kidney and Nephron (Glomerulus and PCT) Compare the composition of the blood entering and leaving the kidney Label and annotate the ultrastructure of the glomerulus Describe the process of ultrafiltration Describe the role of the proximal convoluted tubule in selective reabsorption

Drawing a Kidney

Use page 487 – 488 to describe the differences between the composition of blood in the renal artery and renal vein

Data Q page 488

The Glomerulus What does not pass from the blood into the glomerolus? Why?

The Glomerulus The blood vessel leaving the glomerulus is narrower than the vessel entering. This creates high pressure for ultrafiltration. Particles less than 65,000 atomic mass units can pass through. Proteins and cells are bigger than this.

Fenestrations Basement membrane Podocytes

Qs

Glomerular Filtrate Urine 180 dm-3 per day Contains 1.5 kg salt and 5.5 kg glucose Urine 1.5 dm-3 per day Contains no glucose and far less than 1.5 kg salt. WHERE DOES IT GO????!!!

Proximal Convoluted Tubule Draw a simple cross section of the PCT Describe the methods used to reabsorb substances in the PCT. Show these on your diagram. Explain how a tubule cell is adapted for its function

How are these cells adapted for their function? Microvilli to increase SA Mitochondria to produce ATP. energy

Qs PCT How does the video contradict the textbook? Which is correct? Do some further research.

Selective Reabsorption Sodium ions – active transport from PCT to outside tubule. Then pass to peritubular capillaries. Chloride ions – attracted to the area outside of the tubule by the electrical gradient set up by the sodium ions. Salts are therefore said to be actively transported out of the PCT Glucose and amino acids – co transported out of the tubule by proteins in the outer membrane of the tubule cells. Sodium ions move down conc gradient from outside tubule cells to inside. The provides energy for glucose to move at the same time into the fluid outside the tubule. Water – pumping solutes out creates a solute conc gradient. Water follows by osmosis