Weak peristalic waves pass along stomach wall every

Options

A. 20 seconds
B. 30 seconds
C. 15 seconds
D. 10 seconds

Explanation

To solve the question regarding the frequency of weak peristaltic waves passing along the stomach wall, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Peristaltic Waves**:
- Peristaltic waves are the rhythmic contractions of the muscles in the gastrointestinal tract that help move food along the digestive system.

2. **Identify the Frequency of Peristalsis in the Stomach**:
- The frequency of peristalsis varies in different parts of the digestive system. For the stomach, it is known that there are approximately 3 peristaltic movements per minute.

3. **Convert Frequency to Time**:
- Since we need to find out how often these waves occur in seconds, we can convert the frequency from per minute to per second.
- There are 60 seconds in a minute, so we can calculate the time interval for each peristaltic wave by dividing the total seconds in a minute by the number of movements per minute.

4. **Calculate the Time Interval**:
- Using the formula:
\[ \text{Time interval (in seconds)} = \frac{60 \text{ seconds}}{\text{Number of movements per minute}} \]
- Plugging in the values:
\[ \text{Time interval} = \frac{60 \text{ seconds}}{3 \text{ movements per minute}} = 20 \text{ seconds} \]

5. **Final Answer**:
- Therefore, weak peristaltic waves pass along the stomach wall every **20 seconds**.