You label the developing corticospinal neurons of a cat with a fluorescent compound that permits axon visualization. You see that in the spinal cord, fluorescence is found on only one side of the spinal cord. This finding suggests that the age of the animal is most likely

Question

Quizplus · Accepted Answer

The presence of fluorescence on only one side of the spinal cord suggests that the corticospinal tract axons have already crossed the midline (decussated) and are descending on the contralateral side. This decussation occurs around the time of birth in cats, which is approximately 25 days of gestation. Therefore, the animal is most likely at least 25 days old.

You Label the Developing Corticospinal Neurons of a Cat with a Fluorescent