The correct Answer is A-3, B-4, C-2, D-1
Explanation
The human excretory system is responsible for filtering waste products from the blood and expelling them from the body. This system comprises several organs, each with a specific function in the process of urine formation, storage, and elimination.
Statement-wise Analysis
- A. Kidney - 3. Forms urine by filtration
- Correct: The kidneys are the primary excretory organs. They contain millions of nephrons, which are the functional units responsible for filtering blood to form urine through processes like glomerular filtration, tubular reabsorption, and tubular secretion.
- B. Ureter - 4. Conveys urine from kidney to bladder
- Correct: Ureters are muscular tubes that transport urine from the renal pelvis of each kidney to the urinary bladder. Peristaltic contractions of the ureter walls propel urine downwards.
- C. Urinary bladder - 2. Stores urine
- Correct: The urinary bladder is a muscular sac that temporarily stores urine received from the ureters until it is voluntarily released from the body.
- D. Urethra - 1. Conducts urine to the exterior
- Correct: The urethra is a tube that carries urine from the urinary bladder to the outside of the body. In males, it also serves as a passageway for semen.
Key Takeaway
The human excretory system involves a sequential process where kidneys filter blood to form urine, ureters transport it, the bladder stores it, and the urethra expels it.