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VOLUNTEERS ARE WANTED. WE NEED FOLLOWING:
- Media Spokesperson
- Creative Writer
- Graphic Designer
- Marketing Specialist
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 All
living creatures are made up of cells. Groups of cells, similar in appearance and with the same function, form tissue. The brain is a soft, spongy mass of nerve and supportive tissue connected to the spinal cord. There are two types of brain cells - neurons and neuroglia. Nerves in the brain and spinal cord transmit messages throughout the body.
The human brain is the center of the central nervous system in humans, as well as the primary control center for the peripheral nervous system. The brain controls "lower", or involuntary, autonomic activities such as heart rate, respiration, and digestion. The brain also controls "higher" order, conscious activities, such as thought, reasoning, and abstraction.[18] The human brain is generally regarded as more capable of these higher order activities, and more "intelligent" in general, than any other species. While other animals are capable of creating structures and using simple tools — mostly as a result of instinct and learning through mimicry — human technology is vastly more complex, constantly evolving and improving with time. Even the most ancient human tools and structures are far more advanced than any structure or tool created by any other animal.
The human ability to think abstractly may be unparalleled in the animal kingdom. Human beings are one of only six species to pass the mirror test — which tests whether an animal recognizes its reflection as an image of itself — along with chimpanzees, bonobos, orangutans, dolphins and pigeons. Human beings under the age of 2 typically fail this
test.
The brain perceives the external world through the senses, and each individual human is influenced greatly by his or her experiences, leading to subjective views of existence and the passage of time.
 
The Cranium
A sensible place to start, the cranium, or skull, provides many functions. The primary function of the skull is of course to protect the brain. We immediately begin to see evidence of this function when we look at how the skull is formed.
As you can see, the skull is made up of interconnecting plates. What is so fascinating is the way that the structure and position of these plates closely mirrors the structure of the brain.
Compare the diagram on the left with the next diagram down the page, and one can see distinct
similarities. Click here for pop-up version of the diagram to study.
Cerebrum/Cerebral Hemispheres
Moving inside the skull, we find the largest area of the brain is the cerebrum, which consists of the right and left hemispheres (halves). In general, the right cerebral hemisphere controls the left side of the body and the left cerebral hemisphere controls the right side of the body.
Each hemisphere is comprised of four sections called lobes: frontal, parietal, temporal, and occipital. Each lobe controls a specific group of activities. The outer layer of the cerebrum is made up of gray matter- the bodies of nerve cells. Nerve cells control brain activity. The inner portion of the cerebrum is mostly 'white matter' - nerve fibres called axons. White matter carries information between nerve cells (neurons) by conducting electrical impulses.
The Cranial Nerves
Twelve pairs of cranial nerves arise symmetrically from the base of the brain and are numbered, from front to back, in the order in which they arise. They connect mainly with structures of the head and neck, such as the eyes, ears, nose, mouth, tongue, and throat. Some are motor nerves, controlling muscle movement; some are sensory nerves, conveying information from the sense organs; and others contain fibres for both sensory and motor impulses.
 The Pons
Continuous with and below the midbrain and directly in front of the cerebellum is a prominent bulge in the brain stem called the pons (see diagram). The pons consists of large bundles of nerve fibres that connect the two halves of the cerebellum and also connect each side of the cerebellum with the opposite-side cerebral hemisphere. The pons serves mainly as a relay station linking the cerebral cortex and the medulla oblongata.
Reticular Formation
Running up the brain stem from the medulla oblongata through the pons and the midbrain is a netlike formation of nuclei known as the reticular formation. Is effectively connected to all adjacent parts of the brain.
The Ventricles
We find that four connected cavities called ventricles contain choroid plexus which produces spinal fluid. The fluid flows through the ventricles and the around the meninges.
There are two lateral ventricles, one in each cerebral hemisphere. The third ventricle is beneath the corpus callosum and surrounded by the thalamus. The fourth ventricle is an expansion of the central canal of the medulla oblongata.
 The Tentorium
The tentorium is a flap of meninges separating the cerebral hemispheres from the structures in the posterior fossa. The supratentorium is the name given to the area above the tentorium containing the cerebral hemispheres. Below the tentorium, the Posterior Fossa (infratentorium) is the area within the skull that contains the cerebellum and the brain stem.
Pineal Gland
The pineal gland lies below the corpus callosum. It produces the hormone melatonin. This hormone is believed to control the biological rhythms of the body.
The Pituitary Gland
The pituitary gland is attached to, and receives messages from, the hypothalamus. The pituitary gland is composed of two lobes, the anterior and the posterior. Several hormones are produced by the pituitary including prolactin, corticotropin, and human growth hormone.
 Brain Cells
There are two main types of brain cells: neurons and neuroglia. Neurons are responsible for the transmission and analysis of all electrochemical communication within the brain and other parts of the nervous system. Each neuron is composed of a cell body called a soma, a major fiber called an axon, and a system of branches called dendrites. Axons, also called nerve fibres, convey electrical signals away from the soma and can be up to 1 m (3.3 ft) in length. Most axons are covered with a protective sheath of myelin, a substance made of fats and protein, which insulates the axon.
Myelinated axons conduct neuronal signals faster than do unmyelinated axons. Dendrites convey electrical signals toward the soma, are shorter than axons, and are usually multiple and branching.
Neuroglial cells are twice as numerous as neurons and account for half of the brain's weight. Neuroglia (from glia, Greek for "glue") provide structural support to the neurons. Neuroglial cells also form myelin, guide developing neurons, take up chemicals involved in cell-to-cell communication, and contribute to the maintenance of the environment around neurons.
Cerebrospinal Fluid
CSF is a clear colourless fluid contained in the subarachnoid space and ventricular system of the brain and spinal cord. Its appears to act as a cushion, protecting the brain from sudden movements which may otherwise cause contact between cortex and skull. In addition it has a nutrient and immunological (protection against infection, disease, etc) function.
CSF is a secretion product mainly of the choroid plexus on the ventricles but also of the ependymal linig of the ventricles of the brain and possibly of the cerebral subarachnoid space. It assumes its final composition as a result of material exchange between with the blood and adjacent brain tissue. A flow of CSF (see diagram) is produced from the ventricles into the space. CSF circulates through the Foramen of Monro from the lateral to the third ventricle, down the Aqueduct of Sylvius to the fourth ventricle and into the subarchnoid space via the posterior Foramen of Magendie and the lateral Foramina of Luschka. Some of the CSF travels down the central canal of the spinal cord.
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