Question

A plant researcher wants to construct a synthetic cellulose fiber from 20 glucose molecules. How many molecules of CO2 and glyceraldehyde-3-phosphate are needed to construct the fiber?

A. 20, 40
B. 120, 60
C. 120, 40
D. 20, 60
E. 120, 120

Answer 1

For constructing a synthetic cellulose fiber from 20 glucose molecules, a plant researcher would need 120 molecules of CO2 and 40 molecules of glyceraldehyde-3-phosphate.

Step-by-step explanation:

A plant researcher constructing a synthetic cellulose fiber from 20 glucose molecules would need to know the input molecules required for this synthesis. Each glucose molecule is formed from 6 molecules of carbon dioxide in the Calvin cycle during photosynthesis. Additionally, each glucose molecule is created from two molecules of glyceraldehyde-3-phosphate (G3P), which further implies that a total of 40 G3Ps are needed to create 20 glucose molecules since two G3Ps combine to form one glucose.

For 20 glucose molecules, the researcher would therefore require:

• 20 glucose x 6 CO2/glucose = 120 CO2
• 20 glucose x 2 G3P/glucose = 40 G3P

So the correct answer is C. 120 molecules of CO2 and 40 molecules of glyceraldehyde-3-phosphate (G3P) are needed to construct the fiber.