Welcome to our Webquest for Science enthusiasts ETC.. Did you know that our body is full of cells that transmit signal around the body? The system that is responsible for this operation is the NERVOUS SYSTEM. It lets people and animals respond to what is around them.
As you go through this webquest, you will find out the answers to these essential questions:
1. Which are the structures that are part of the nervous system?
2. Which are the main cells of the nervous system?
3. What are the functional differences between neurons and glial cells?
4. What are the three main parts into which a neuron can be divided? What are their respective function?
5. What are synapses?
6. According to the function of the transmitted neural impulse which are the types of neurons? How different are the concepts of afference and efference of the neural impulse transmission?
7. What are nerves?
8. What are the cells that produce the myelin sheath? Of which substance is the myelin sheath formed?
9. What is the difference between brain and cerebrum? What are the main parts of these structures?
10. Which is the brain region responsible for the coordination and equilibrium of the body?
Task
Thinking Cap
For grades 3-12
Display your brain on a "Thinking Cap." Thinking Caps are created from papier (or paper) mache.
Create the Form: First, create the brain form for the cap. You can create a form from wire (e.g., chicken wire) or a balloon or use a bowl to build your cap around. You could even ball up some newspaper and cover it will masking tape. The form should have the approximate size and shape of your head so you can wear it.
Create the Structure: Cut strips of newspaper and glue them to the form using papier mache paste. Pastes can be made from:
White glue and water (about 2 parts glue to 1 part water)
White flour, salt and water (about 1 part flour to 1 part water with a few tablespoons of salt)
Liquid starch
Coat the newspaper strips with the paste, and place them on the form. Let each newspaper layer dry before you add a new layer. Add enough layers to give you a strong structure. When the structure is dry, remove the underlying form. You may have to cut the edges of the structure and repair the sides for a good fit on your head.
Decorate the Thinking Cap: you can paint the Thinking Cap with the lobes of the brain (see photo) or with the different areas of the cerebral cortex.
SAMPLE PRODUCT
Process
HOW NERVOUS SYSTEM WORKS?
In the cellular-level, the stressed system is described by the existence of a special kind of cell, named the neuron, also referred to as a "nerve mobile". Neurons have unique constructions that let them send signs quickly and just to other cells. They deliver these signs in the kind of electrochemical waves touring along slender fibers called axons, which trigger chemicals called neuro-transmitters to be discharged at junctions called synapses. A mobile that gets a sign from a neuron could be thrilled, inhibited, or else modulated. The links between neurons type neural circuits that create a being's understanding of earth and determine its behaviour. Together with neurons, the stressed system includes other specific cells called glial cells (or only glia), which supply structural and metabolic assistance.
Nervous systems are observed in most multicellular creatures, but differ significantly in complexness.The single multicellular creatures without any nervous program at each one is sponges, placozoans and mesozoans, that have really uncomplicated body plans. How big is the body's nervous system ranges from a hundred or so cells in the worms, to around the purchase of 100 billion cells in persons. human nervous system, cns & pns, peripheral nervous system central nervous system, nervous system functions.
Here are some other FACTS that are significant for you to know:
1. The structures that form thenervous systemcan be divided into the centralnervous system(CNS) and theperipheral nervous system(PNS).
The organs of the CNS arethe brain(cerebrum, brainstem and cerebellum) and spinal cord. The PNS is made of nerves and neural ganglia. Besides these organs the meninges (dura-mater, arachnoid and pia-mater) are part of thenervous systemtoo since they cover and protect the encephalon and the spinal cord.
2. The main cells of the nervous system are the neurons. Besides the neurons the nervous system is also constituted of glial
3. Glial cells and neurons are the cells that form the nervous system. Neurons are cells that have the function of receiving and transmitting the neural impulses and glial cells (astrocytes, microgliacytes, ependymal cells and oligodendrocytes) are the cells that support, feed and insulate (electrically) the neurons. The Schwann cells that produce the myelin sheath of theperipheral nervous system can also be considered glial cells.
4. The three mains parts into which a neuron can be didactically divided are: dendrites, cell body and axon.
Dendrites are projections of the plasma membrane that receive the neural impulse from other neurons. The cell body is where the nucleus and the main cellular organelles are located. Axon is the long membrane projection that transmits the neural impulse at distance to other neurons, to muscle cells and to other effector cells.
5. Synapses are the structures that transmit the neural impulse between two neurons.
When the electric impulse arrives the presynaptic membrane of the axon releases neurotransmitters that bind to postsynaptic receptors of the dendrites of the next cell. The activated state of these receptors alters the permeability of the dendritic membrane and the electric depolarization propagates along the neuron plasma membrane to its axon.
6. There are three types of neurons: afferent neurons, efferent neurons and interneurons. Afferent neurons are those that only transmit sensory information from the tissues to neural nuclei and ganglia (where they make connection with interneurons or effector neurons). Efferent neurons are those that transmitcommands to tasks performed in several partsof the body. Interneurons, also known as association neurons or relay neurons, serve as connection between two other neurons.
Afference is the conduction of sensory impulses and efference is the conduction of effector impulses (impulses that command some body action).
7. Axons extend throughout the body inside nerves. Nerves are axon-containing structures presenting many axons and covered by connective tissue. The nerves connect neural nuclei and ganglia with the tissues.
8. Nerves may contain only sensory axons (sensory nerves), only motor axons (motor neurons) or both types of axons (mixed nerves).
9. In the central nervous system (CNS) the myelin sheath is made by apposition of oligodendrocyte membranes. Each oligodendrocyte can cover portions of axons of several different neurons. In the peripheral nervous system (PNS) the myelin sheath is made by consecutive Schwann cell membranes covering segments of a single axon. The Ranviers’ nodes appear in the intercellular space between these cells.
The myelin sheath is rich in lipids but it also contains proteins.
10. The concept of brain, or encephalon, comprehends the cerebrum (mostly referred to as the hemispheres, but actually the concept also includes thethalamus and the hypothalamus), the brainstem (m
idbrain, pons and medulla) and the cerebellum. Brain and spinal cord form the central nervous system(CNS).
In the central nervous system the cerebellum is the main controller of the motor coordination and equilibrium of the body. (Do not confuse this with muscle command, performed by the cerebral hemispheres).
You can also watch this PowerPoint Presentation for more knowledge intake !! FEED and NOURISH your brain !!
As the most complex system, the nervous system serves as the body control center and communications electrical-chemical wiring network. As a key homeostatic regulatory and coordinating system, it detects, interprets, and responds to changes in internal and external conditions. The nervous system integrates countless bits of information and generates appropriate reactions by sending electrochemical impulses through nerves to effector organs such as muscles and glands. The brain and spinal cord are the central nervous system (CNS); the connecting nerve processes to effectors and receptors serve as the peripheral nervous system (PNS). Special sense receptors provide for taste, smell, sight, hearing, and balance. Nerves carry all messages exchanged between the CNS and the rest of the body.
_20.jpg)
_32.jpg)
_8.jpg)