Write one specific function each of the following organs in relation with excretion in human beings :
(i) Renal Artery
(ii) Urethra
(iii) Glomerulus
(iv) Tubular part of nephron Urethra
Generated by claude-sonnet-4-6 · 2026-06-11 09:50 · grounding rag
Model Answer
(i) Renal Artery: It supplies oxygenated blood (containing nitrogenous wastes) to the kidneys for filtration.
(ii) Urethra: It carries urine from the urinary bladder to the outside of the body for expulsion.
(iii) Glomerulus: It is a cluster of capillaries where filtration of blood takes place — waste products, water, glucose, salts are filtered out of the blood into the Bowman's capsule.
(iv) Tubular part of nephron: It selectively re-absorbs useful substances such as glucose, amino acids, salts and a major amount of water from the filtrate back into the blood.
Source: Chapter 5, Section 5.5.1 – Excretion in Human Beings
---
Explanation
- Examiners expect one specific function per organ — do not describe structure.
- Key terms to use: filtration (glomerulus), reabsorption (tubule), expulsion/release (urethra), blood supply with wastes (renal artery).
- The tubule's role in selective reabsorption is a frequently tested point — mention at least two substances reabsorbed.
- Keep each point to one sentence; these are likely 1-mark each.