The reflex pathway consists of retinal ganglion cells, which convey information from the photoreceptors to the optic nerve which connects to the pretectal nucleus of the high midbrain. It bypasses the lateralgeniculate nucleus and the primary visual cortex.
The River Nile is about 6,670 km (4,160 miles) in length and is the longest river in Africa and in the world. Although it is generally associated with Egypt, only 22% of the Nileâs course runs through Egypt.
According to their new estimate, the Amazon is 6,800 kilometers (4,250 miles) long. The Nile is thought to be 6,695 kilometers (4,160 miles) long. As the BBC reported, assessing the exact length of a river can be difficult, and the calculation depends partly on identifying the riverâs source. Before the announcement, the Nile had been regarded as only slightly longer than the Amazon, so this new finding was not shocking, but the Amazonâs new primacy in river length could face future challenges as both rivers continue to be explored.