A volcano is a vent or fissure in Earth's crust through which lava, ash, rock and gases erupt. A volcano is also a mountain formed by the accumulation of these eruptive products.Let's take a look at how volcanoes form: Earth's crust is 40 to 250 miles (64 to 402 kilometers) thick.irborne fragments of lava, called tephra, are ejected from a single vent. The lava cools rapidly and builds up around the vent, forming a crater at the summit. Cinder cone volcanoes are fairly small, generally only about 300 feet (91 meters) tall and not rising more than 1,200 feet (366 meters).
10 hilariously insightful foreign words. The glossopharyngeal nerve is also called the ninth cranial nerve. Cranial nerves are vital nerves that arise from the brain that help the brain control muscles, process the five senses, and control glands in the body.
The neurons system is divided into the central nervous system (CNS- the brain and spinal cord) and the peripheral nervous system (PNS), which connects to CNS to the rest of the body by means of nerves. The PNS has two main divisions. The somatic nervous system enables voluntary control of the skeletal muscles. The autonomic nervous system, through its sympathetic and parasympathetic divisions, controls involuntary muscles and glands. Neurons are the basic building blocks of the nervous system. Sensory neurons carry incoming information from sense receptors to the brain and spinal cord, and motor neurons carry information from the brain and spinal cord out to the muscles and glands. Interneurons communicate within the brain and spinal cord and between sensory and motor neurons.