Question

Diagram represents a nephron and its blood supply. Study the diagram and answer the following question.

i) Label parts 1,2,3 and 4

(ii) State the reason for the high hydrostatic pressure in the glomerulus.

(iii)Name the blood vessel which contains the least amount of urea in the diagram.

(iv)Name the two main stages of urine formation.

(v)Name the part of the nephron which lies in the renal medulla.

Answer 1

(i) A nephron is the structural and functional unit of the kidney.

Here are the different parts of the nephron

1. Collecting duct: The filtered urine is stored temporarily in the collecting duct. It is the extreme end of the nephron.
2. Distal convoluted tubule: It is a short segment between the Loop of Henle and the collecting duct. It regulated the water and salts from the urine
3. Loop of Henle: The U-shaped structure in the nephron is referred to as the loop of Henle. It helps with the recovery of sodium chloride.
4. Bowman’s capsule: The C-shaped cup-like structure at the extreme up of the nephron is the Bowman’s capsule It is continuous with the convoluted tubule.

(ii)

1. The afferent arteriole when entering the Bowman’s capsule forms a complex knot-like structure called the glomerulus.
2. A pressure is created because the efferent arteriole is slightly narrower in diameter than the afferent arteriole called hydrostatic pressure.

(iii)

Efferent arteriole

1. Efferent arteriole that has the lower diameter then afferent arteriole contains the least amount of urea.

(iv) The two main stages of Urine formation are

a. Ultrafiltration

1. This is the stage where the blood is filtered.
2. It takes place in the Bowman’s capsule.
3. The filtration of salts, glucose, and urea takes place here.

b. Reabsorption

1. This process takes place at 3 stages where water, salts, and glucose are reabsorbed.
2. The reabsorption happens at the proximal and distal convoluted tubule and the loop of Henle.

(v) Part of the nephron which lies in the renal medulla.

1. It is the innermost region of the kidney and contains triangular-shaped segments called renal pyramids.
2. The loop of Henle found in the innermost region which is the renal medulla of the kidney.