Fun Science Projects & Experiments
More Lessons for Science Projects
A collection of science projects, videos and experiments for various grades and topics.
Science Projects or Science Experiments: Grades 5 & 6
Nerves and Neurons
How the Body Works : Anatomy of a Nerve
More than ten thousand million nerve cells and their fibers, or axons, make up the nervous system. The axons are grouped together in nerve trunks containing sensory fibers, which conduct information from the sensory organs to the central nervous system, and motor fibers, which carry information to the central nervous system of the body. The nerve fibers which carry information quickly are enclosed in a thick sheath made of the fatty substance myelin. They are called myelinated nerve fibers. The myelinated sheath has regular indentations along its length called the nodes of Ranvier. The nonmyelinated nerve fibers, which carry information slowly, are grouped together and enclosed in a single sheath.
The anatomy of a nerve includes: the cell body, which is composed of cytoplasm and contains the cell nucleus; the nucleus, which contains the information needed to control the activity of the neuron; the dendrites, outgrowths of the cell body to which and from which they conduct impulses; the epineurium, a fibrous sheath that surrounds the whole nerve; the perineurium, the connective tissue sheath that surrounds bundles of nerve fibers; the endoneurium, the fine sheath of connective tissue around each nerve bundle; the axon, the extended fiber of the nerve cell which carries impulses to and from the cell body; the fatty myelin sheath, the insulating coat that separates the axon in a nerve bundle; the Schwann cell nucleus, the mechanism responsible for the production and maintenance of the myelin sheath and the Nodes of Ranvier, constrictions in the myelin sheath.
How the Body Works: Anatomy of the Brain Stem
The brain stem , which is only two and a half inches long, is seen here cut from top to bottom and laid open, in a similar way to which a book is opened. The central dark area is the reticular formation. The left side shows the motor nuclei of the cranial nerves and the right side illustrates their sensory nuclei. The anatomy of the brain includes: the motor nuclei of cranial nerves, this one represents the oculomotor nucleus; the choroid plexus, which secretes a clear, watery fluid--the cerebrospinal fluid; a sensory nucleus of the fifth cranial nerve; the thalamus, which receives both motor and sensory nerve fibers as they pass into and out of the brain; the trigeminal nerve, which is comprised of single fibers which unite to form a nerve bundle; the pituitary stalk, which is part of the forebrain and lies above the pons; the optic nerve, which splits to enter the chiasma and lies in front of the brain stem; the pons, which is made up of transverse nerve fibers interwoven with longitudinal nerve fibers; the medulla oblongata, which is the lower part of the brain stem; the spinal cord, a cord of central gray matter surrounded by white matter; motor nerve bundles, which emerge from the right side of the brain and cross to supply the body's left side; the sensory nerve bundles, which arise from the left side of the body and pass to the right side of the brain after crossing in the medulla; and the motor and sensory nerve fibers, which pass through the brain stem on their way into and out of the spinal cord, and cross in the medulla to serve and supply areas on the opposite sides of the body.
Anatomy of a Neuron
This video discusses the basic features of neurons and how they communicate with one another.
Anatomy and Physiology, The Nerve Cell
The Nerve Cell is the functional unit of the peripheral nervous system. This presentation details the anatomical structures involved in nerve conduction; the dendrite, the axon, the pre-/post synaptic juncture, and the role of neurotransmitters in normal, and abnormal states of the nervous system.
Try the free Mathway calculator and
problem solver below to practice various math topics. Try the given examples, or type in your own
problem and check your answer with the step-by-step explanations.