Urinary excretion =

Options

A. `GF-SR+TS`
B. `GF+SR+TS`
C. `GF+SR-TS`
D. `GF-SR-TS`

Answer

**Step-by-Step Solution:**

1. **Understanding Urinary Excretion:**
- Urinary excretion refers to the process through which waste products are eliminated from the body in the form of urine. It is a primary route for the excretion of metabolic waste.

2. **Normal Urinary Excretion Rate:**
- A normal urinary excretion rate for a healthy individual is approximately 60 milliliters per hour or more.

3. **Key Components of Urinary Excretion:**
- The process of urinary excretion involves three main components:
- **Glomerular Filtration (GF):** This is the rate at which blood is filtered through the glomeruli in the kidneys. It indicates how much blood passes through the glomeruli per minute.
- **Secretion Rate (SR):** This refers to the process occurring mainly in the proximal convoluted tubule (PCT) where excess solutes and ions are secreted into the filtrate.
- **Reabsorption Rate (TS):** This is the process where certain substances (like water and important ions) are reabsorbed back into the bloodstream from the filtrate.

4. **Equation for Urinary Excretion:**
- The urinary excretion can be calculated using the following equation:
\[ \text{Urinary Excretion} = GF - (SR + TS) \]
- Here, GF is the glomerular filtration rate, SR is the secretion rate, and TS is the reabsorption rate.

5. **Conclusion:**
- By applying this equation, we can determine the actual amount of urine formed, which represents the urinary excretion from the body.

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