Question

7. During the course of normal human development, the muscle myosin protein becomes expressed in muscle cells but not in non-muscle cells, such as liver cells. Based on this information and your knowledge about biology, select true or false for each of the following statements.
   
   a) T/F This expression pattern could result from the muscle myosin gene being present in muscle cells but not in liver cells.
   b) T/F This expression pattern could result from the regulatory sequence of the muscle myosin gene being different in muscle cells compared to liver cells.
   c) T/F This expression pattern could result from epigenetic modifications, such as DNA methylation, being present on the myosin gene in liver cells but not in muscle cells.
   d) T/F This expression pattern could result from a transcription factor that activates expression of the muscle myosin gene being present in muscle cells but not in liver cells.

The EOT1 gene is required to promote toe development in normal mice. A mutation in this gene results in a paw with two extra toes. Based on this information and your knowledge about biology, select true or false for each of the following statements.

a) T/F The mutation could be located in a regulatory region of the EOT1 gene where an inhibitor protein normally binds.
b) T/F The two extra toes could result from a mutation in the EOT1 gene that causes the EOT1 protein to be nonfunctional.
c) T/F The mutation could result in the mouse having lower than average fitness.
d) T/F If the extra toes result in the mouse having increased fitness, the mutation could increase in frequency in a population of mice over time.
e) T/F If the extra toes do not cause any change in the fitness of the mouse, the mutation could increase in frequency in a population of mice over time.

Answer 1

1. A. This expression pattern could result from the muscle myosin gene being present in muscle cells but not in liver cells = False
b) This expression pattern could result from the regulatory sequence of the muscle myosin gene being different in muscle cells compared to liver cells = False
c) This expression pattern could result from epigenetic modifications, such as DNA methylation, being present on the myosin gene in liver cells but not in muscle cells = true
d) This expression pattern could result from a transcription factor that activates expression of the muscle myosin gene being present in muscle cells but not in liver cells = True