​Identify the correct sequential order of the excretory system in human beings.​

Correct option is C

​The correct answer is (c)  Kidney → Ureters → Urinary Bladder → Urethra

The excretory system in humans is responsible for removing metabolic waste from the body. The correct sequence follows this pathway:

1. Kidney

   • The kidneys filter blood to remove waste, toxins, and excess fluids, forming urine.
   • Each kidney contains around one million nephrons, which are the functional units of filtration.

2. Ureters

   • The urine travels from each kidney through two muscular tubes called ureters to the urinary bladder.
   • These tubes prevent the backflow of urine using peristaltic movements.

3. Urinary Bladder

   • The urinary bladder is a hollow, muscular organ that stores urine temporarily.
   • It expands as urine collects and contracts when urine is ready to be expelled.

4. Urethra

   • The urine is expelled from the bladder through the urethra, the final passageway of the excretory system.
   • In males, the urethra also serves as a passage for semen, whereas in females, it functions solely for urination.

Information Booster:

• The right kidney is slightly lower than the left to accommodate the liver.
• The nephrons in the kidney perform ultrafiltration, reabsorption, and secretion.
• The average adult bladder can store about 400-600 ml of urine.
• The internal urethral sphincter is involuntary, while the external urethral sphincter is under voluntary control.
• Urinary tract infections (UTIs) are more common in females due to their shorter urethra.
• The medical term for painful urination is dysuria.