Case 2 : the biological process involved in the removal of harmful metabolic wastes from the bosy is called excertion .Different organisms use varied strategies to do this Many unicellular organisms remove these wastes by simple diffusion from the body surface into the surrounding water while complex multicellular organisms use specialised organs to perform the same function .
the excretory system of humna beings include :

Options

A. a pair of kidney , a pair of urinary bladders , a urinary bladders , a ureter , and a urethra.
B. a kidney , a ureter , a urinary bladder and a urethra .
C. a pair of kidney , a pair of ureters , a pair of urinary bladders and a urethra .
D. a pair of kidney , a pair of ureters , a urinary bladder and a urethra .

Explanation

**Step-by-Step Solution:**

1. **Understanding Excretion**: Excretion is the biological process of removing harmful metabolic wastes from the body. This process is vital for maintaining homeostasis and preventing toxicity from waste accumulation.

2. **Different Strategies of Excretion**: Various organisms have different methods of excretion. Unicellular organisms typically utilize simple diffusion to expel waste directly into their surrounding environment, while multicellular organisms have developed specialized organs for this purpose.

3. **Excretory System in Humans**: In humans, the excretory system is composed of several key components that work together to remove waste from the body.

4. **Components of the Human Excretory System**:
- **Kidneys**: There are two kidneys, which are bean-shaped organs responsible for filtering blood and producing urine.
- **Ureters**: These are tube-like structures that transport urine from the kidneys to the urinary bladder.
- **Urinary Bladder**: This is a muscular sac that stores urine until it is ready to be expelled from the body.
- **Urethra**: This is the tube through which urine is discharged from the body.

5. **Conclusion**: The complete excretory system in humans includes a pair of kidneys, a pair of ureters, a urinary bladder, and a urethra.

6. **Final Answer**: Therefore, the correct answer to the question regarding the components of the human excretory system is: A pair of kidneys, a pair of ureters, a urinary bladder, and a urethra.

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