The researcher measures the concentration of the polypeptides from different regions in the early embryo and finds the following pattern (darker shading = greater concentration):
Which of the following would be his most logical assumption?
A)The substance has moved quickly from region 5 to region 1.
B)Some other material in the embryo is causing accumulation in region 1 due to differential binding.
C)The cytosol is in constant movement, dispersing the polypeptide.
D)The substance is produced in region 1 and diffuses toward region 5.
E)The substance must have entered the embryo from the environment near region 1.

Question

The researcher measures the concentration of the polypeptides from different regions in the early embryo and finds the following pattern (darker shading = greater concentration): 
Which of the following would be his most logical assumption?
A)The substance has moved quickly from region 5 to region 1. 
B)Some other material in the embryo is causing accumulation in region 1 due to differential binding. 
C)The cytosol is in constant movement, dispersing the polypeptide. 
D)The substance is produced in region 1 and diffuses toward region 5. 
E)The substance must have entered the embryo from the environment near region 1.

Quizplus · Accepted Answer

The pattern of increasing concentration suggests that the polypeptide is being produced in region 1 and then diffusing towards region 5. If the substance had entered from the environment near region 1 (option E), the concentration would not decrease towards region 5. Options A, B, and C are unlikely because they do not fit the observed pattern of concentration.

The Researcher Measures the Concentration of the Polypeptides from Different