Question

Where does the Ultrafiltration process take place?

Answer 1

Hint: In general, Ultrafiltration is a purification process which is pressure driven that separates particulate matter from soluble compounds using an ultrafine membrane.

Complete Answer:
- Ultrafiltration occurs in the Bowman’s capsule of the kidney. Bowman’s capsule is also called the capsula glomeruli or glomerular capsule. It is a part of the nephron ( functional unit of kidneys ).
- Bowman’s capsule is a double walled cup like structure . It contains a dense capillaries network called glomerulus.
- Blood flows in these capillaries through the afferent arterioles and leaves through the efferent arterioles.

Ultrafiltration: It is a pressure driven process.
- In this process, the high hydrostatic pressure forces small molecules such as water, glucose , amino acids, NaCl and urea in a tubular fluid through the filter across the basement membrane of Bowman’s capsule. This process is called the Ultrafiltration.
- The resulting fluid will be virtually free of large proteins and blood cells and is called an ultrafiltrate of glomerular filtrate.
- Glomerular pressure is about 75mm of mercury.
- The components of filtrate such as sodium ions, potassium ions, etc. are then reabsorbed in the renal; tubule.

Selectivity of ions by glomerulus layers:
- The structure of layers of glomerulus are selectively permeable.
 For example – small ions such as potassium ion, sodium ion pass freely while larger proteins such as hemoglobin and albumin cannot pass through it.
- Also negatively charged molecules will pass through in less number than that of positively charged ions.

Note: Ultrafiltration is a very specific process. It is a process by which metabolic wastes are separated from the blood and urine is formed.