**Experiment 1** Yeast suspensions were incubated in flasks containing 10\% solutions of t… — ACT

Experiment 1
Yeast suspensions were incubated in flasks containing $10\%$ solutions of three different sugars (glucose, sucrose, and lactose) at a constant temperature of $35^\circ\text{C}$ . The volume of carbon dioxide ( $\text{CO}_2$ ) gas produced was measured every $5$ minutes for a total of $30$ minutes.

Experiment 2
Yeast suspensions were incubated in flasks containing a $10\%$ glucose solution at four different temperatures ( $15^\circ\text{C}$ , $25^\circ\text{C}$ , $35^\circ\text{C}$ , and $45^\circ\text{C}$ ). The volume of $\text{CO}_2$ gas produced was measured only once, exactly $30$ minutes after incubation began.

Statement to evaluate:
The two experiments differed in their independent variables (sugar type vs. temperature) and also in how the dependent variable ( $\text{CO}_2$ production) was monitored over time.

Answer: Answer

Answer

True

The statement is correct because Experiment 1 manipulates sugar type (independent variable) and collects data dynamically at

5

-minute intervals, while Experiment 2 manipulates temperature (independent variable) and collects a single endpoint data point at

30

minutes.

Step-by-Step Solution

Identify and compare the independent variables of both experiments.

In Experiment 1, the sugar type (glucose, sucrose, lactose) is varied, while in Experiment 2, the temperature (

15^\circ\text{C}

25^\circ\text{C}

35^\circ\text{C}

45^\circ\text{C}

) is varied. These independent variables are different.

To determine if the independent variables differ between the experimental designs.

Identify and compare the methods of monitoring the dependent variable.

In Experiment 1, the volume of

\text{CO}_2

is measured repeatedly (every

5

minutes for

30

minutes) to observe the rate of reaction. In Experiment 2, the volume is measured only once at the end (

30

minutes). These monitoring intervals/methods are different.

To determine if the method of tracking the dependent variable differs between the experimental designs.

Evaluate the statement based on the findings from steps 1 and 2.

Since both the independent variables and the monitoring protocols differ, the statement is correct.

To arrive at the final true/false evaluation.

Key Concept

Comparing and Contrasting Multiple Experimental Designs

Question

Answer

Step-by-Step Solution

Key Concept

Common Mistakes

Topics

More questions from this topic