Question

What are the functions of Bowman’S capsule and Glomerulus?
A. Filtration blood.
B. Reabsorption of ions from the blood.
C. Reabsorption of hormones from the blood
D. Reabsorption of water from the blood

Answer 1

Hint: The Bowman’S capsule is a cup-like structure at the beginning of the nephron in the kidney of mammals. The glomerulus is the network of capillaries present within the Bowman capsule.

Complete answer:
Each human kidney has about one million nephrons. So the total number of nephrons in the two kidneys is two million. The nephron is the functional unit of each kidney.

The nephron has two parts: The renal tubule and the glomerulus. Together the renal tubule and the glomerulus constitute a unit called the renal corpuscle or the Malpighian body.

The renal tubule begins as the Bowman’S capsule which is a doubled walled cup-like structure. The outer layer is called the parietal layer and is made of simple squamous epithelium. The inner or the visceral layer is made up of podocytes or cells with foot like processes. The podocytes leave some minute spaces called the filtration slits or the slit pores. The space between the parietal and visceral layers is the Bowman space.

The glomerulus or the tuft of capillaries formed by the renal artery in the Bowman’S capsule enter the capsule as the afferent arteriole and leave as the efferent arteriole.

The two layers of the Bowman’S capsule along with the glomerular basement membrane form the filtration membrane through which blood is filtered under the influence of capillary blood pressure by a process called ultrafiltration.

The process of ultrafiltration is accompanied by the reabsorption of various substances like amino acids and glucose actively and passive absorption of water into the tubules. Reabsorption is mainly the function of the parts of the nephron present distally like the Proximal and Distal convoluted tubules and the Loop of Henle while The Bowman’S capsule and Glomerulus are chiefly concerned with filtration of blood to form the ultrafiltrate.

Hence, The correct answer is option (A).

Note: The kidneys filter around $1100-1200ml$ of blood per minute which is roughly $(\dfrac{1}{5})^{th}$ that of the blood pumped by the ventricles in a minute. This is done by Bowman's capsule that surrounds the glomerular capillary loops and participates in the filtration of blood from the glomerular capillaries. Bowman's capsule also performs a structural function by creating a urinary space through which filtrate enters the nephron and passes to the proximal convoluted tubule.