Activity:Cellular Respiration in Yeasts

Problem

• Which of the substances – bleach, honey, ketchup, maple syrup, mouthwash, salt, sugar, water, and vinegar – will cause the yeast to undergo cellular respiration?

Hypothesis

I think that…will promote cellular respiration in yeasts because…

Procedure1. Measure 8 mL of each substance

you are testing and pour it into the test tubes with your yeast.

2. Stir.3. Place each test tube into a

beaker of warm water for 10 minutes.

4. Measure the height of the foam in the test tube.

DataSubstance Height

(in cm)

Did cellular respiration occur?

Bleach 1 cm Yes

Honey 4 cm Yes

Ketchup 3 cm Yes

Maple syrup 2.75 cm Yes

Mouthwash 1 cm Yes

Salt 0 cm No

Sugar 2.5 cm Yes

Vinegar 0 cm No

Water 0 cm No

Key Terms• Yeasts – a type of unicellular fungi• Cellular respiration – process in which

mitochondria use glucose and oxygen to produce energy

• Oxygen – one of the substances required for cellular respiration to occur

• Glucose – one of the substances required for cellular respiration to occur – it is a type of sugar that stores energy

• Carbon dioxide – one of the substances produced at the end of cellular respiration

• Water – one of the substances produced at the end of cellular respiration

Data Analysis1. What substances were the best for

promoting cellular respiration in the yeasts?

2. What does a cell have to have in order to do cellular respiration?

3. Why did the substances that promote cellular respiration work better than those that did not?

4. What substances were produced at the end of cellular respiration?