Mercury is a heavy metal that occurs naturally in minerals and rocks. Release of mercury from natural sources has been relativel
y constant over time. However, anthropogenic release of mercury has increased significantly in recent years primarily due to increased fossil fuel mining and combustion. Mercury that is released into the air eventually ends up in soils or surface water. Once in water, microbes convert mercury into methyl mercury, which is absorbed quickly and concentrated in the tissues of predatory fish such as shark and swordfish. Large fish typically concentrate more mercury than small fish. People who eat fish with high methyl mercury concentrations can show tremors, deafness, muscle dysfunction, and attention deficits. Pregnant women and children are especially sensitive to methyl mercury's toxic effects. Learning disabilities and developmental delays are common in children who have been exposed to significant levels of methyl mercury. Based upon the specific health effects described above, mercury would be best classified as a ________.
The neurotoxin is a substance which alters the function as well as the structure of the nervous system. Mercury is a type of neurotoxin. This is caused by the exposure to the mercury. The long term exposure to mercury affects the functioning of the brain. This affects the motor and muscular coordination as an effect of mercury poisoning.
The spinal cord has numerous groups of nerve fibers going towards and coming from the brain
These have been collectively called the ascending and descending tracts of the spinal cord, respectively, these tracts are responsible for carrying sensory and motor stimuli to and from the periphery (respectively)
The ascending tracts transmit sensory information from the sensory receptors to higher levels of the CNS
The descending tracts originate from different cortical areas and from brain stem nuclei
The descending pathway carry information associated with maintenance of motor activities such as posture, balance, muscle tone, and visceral and somatic reflex activity
