Let's break down the given data recorded during the investigation:
The table indicates the number of contractile vacuole contractions per minute for a paramecium placed in various concentrations of hypertonic salt solutions. Here's a detailed look at the data:
1. Salt concentration outside paramecium (Very high):
- Contractions per minute: 2
2. Salt concentration outside paramecium (High):
- Contractions per minute: 8
3. Salt concentration outside paramecium (Medium):
- Contractions per minute: 15
4. Salt concentration outside paramecium (Low):
- Contractions per minute: 22
5. Salt concentration outside paramecium (Very low):
- Contractions per minute: 30
Now, let’s analyze the statement: "The graph has five bars of equal height."
First, we will consider what it means for the bars on a bar graph to have equal height. If the bars were of equal height, it would indicate that the number of contractions per minute is the same across all salt concentrations.
However, when we look at the data:
- Very high salt concentration has 2 contractions per minute.
- High salt concentration has 8 contractions per minute.
- Medium salt concentration has 15 contractions per minute.
- Low salt concentration has 22 contractions per minute.
- Very low salt concentration has 30 contractions per minute.
It is clear from the data that the number of contractions per minute varies significantly across the different salt concentrations. Therefore, the bars on a bar graph would not be of equal height.
A correct statement that can be deduced from the data is:
- "The number of contractions per minute increases as the salt concentration decreases."
This is visible because, as the salt concentration decreases from very high to very low, the number of contractions per minute steadily increases from 2 to 30. This decreasing trend in salt concentration corresponds to an increasing trend in contractions per minute.
