Problem 1 – Alcoholic fermentation

At intervals of 20, 40, and 60 minutes, the tubes are removed. Record the volume of gas produced in each fermentation tube. Each tube is graduated in tenths of a milliliter. (HINT: Look at the amount of gas, not the level of the liquid.)

What gas accumulated in the calibrated portion of the fermentation tube?·

What metabolic pathway is utilized by yeast cells?

Why was amylase added to the third test tube?

Did respiration occur in the beaker containing yeast and starch? Why?

Problem 2 – Carbon dioxide production in germinating seeds

Record the experimental results below.

What color is the phenol red solution in the stock bottle?

What does this indicate about the pH of the phenol red solution in the stock bottle?

What color was the solution in the beaker after exhaling into the solution?

Explain the color change.

Which laboratory setup produced carbon dioxide?

Problem 3 – Measuring metabolic rate
Record the time measurement for the soap film to travel 2 ml of the pipette.

Does this indicate the rodent’s metabolic rate is faster or slower than humans?

The rodents metobolic rate is faster

How does your metabolic rate compare with that of the rodent? Suggest explanations for the similarity or the difference.

Problem 4 – Estimate basal metabolic rate

Record your height, age, weight, and sex. Answers shown are for example – your figures will be different.

Use the Dubois Body Surface Chart to determine the surface area of your body. Follow the directions given above the chart. Record your body surface area.

Estimate your basal metabolic rate for one minute, one hour, and one day. To do this, multiply the heat loss for your age and sex in calories per minute times your body surface area.

Summary Questions:
1. Compare aerobic respiration, anaerobic electron transport, and fermentation using the following table. Refer to your textbook for anaerobic electron transport and lactate fermentation.

2. What human foods are products of fermentation?

3. Explain why the sun is the ultimate source of energy for living organisms.

4. Describe the relationship between photosynthesis and respiration. Include an equation that demonstrates this relationship.

5. In what organelle is pyruvate converted into ATP?

6. Define metabolism.

7. What is the connection between Calories and cellular respiration? Why is human metabolism measured in Calories?

8. Explain how the metabolic rate of an animal can be determined by measuring its rate of oxygen consumption.

9. How does the BMR for a person of your age and sex compare with a rodent’s metabolic rate?

10. What factors other than Basal Metabolic Rate influence the total number of Calories needed in a given amount of time?