Chapter 5 - The nervous system. This chapter addresses the core of the nervous system, specifically the brain, the structures and systems within it, and the spinal cord. It begins with an overview of the structure and function of the brain itself, revealing anatomical features and physiological activity. | Chapter 5 The Nervous System Introduction The nervous system is truly remarkable. Every thought, feeling or action reveals its fascinating activity; consequently, malfunction of the nervous system can have a devastating effect on life. Compose a list of the conditions that you already know that affect the nervous system, add this to your portfolio The Nervous System The nervous system is divided into the central nervous system (CNS), comprising the brain itself and the spinal cord the peripheral nervous system (PNS), encompassing the cranial and spinal nerves. The CNS is an integrated command centre interpreting and responding to sensory impulses. The PNS is divided into sensory (afferent; carrying towards) and motor (efferent; carrying away) divisions. The Brain The brain has the consistency of a soft-boiled egg, the wrinkled appearance of a walnut and no moving parts. It is housed and protected by the skull, or cranium. The brain weighs approximately 1500g and contains more than 100 billion neurons, the fundamental functional unit of the nervous system. The meninges cover, surround and protect the brain, and the spinal cord. They have three layers: The Dura mater Arachnoid membrane Pia mater The Brain The brain is made up of visibly distinct regions the cerebrum the brain stem the cerebellum The cerebral hemispheres are made up of four pairs of lobes: frontal parietal temporal occipital In addition, the cerebrum also contains the diencephalon, which are composed of the thalamus, hypothalamus and epithalamus. Identify the Four Lobes of the Brain Applying Theory to Practice: Exercise What conditions have you heard of that are characterised by bleeding into the spaces between the meninges of the brain? What are the most likely causes of such bleeding? Cerebrospinal fluid (CSF), a clear, colourless, odourless liquid, surrounds the brain and the spinal cord. It acts as a shock absorber, floating and cushioning the brain and spinal cord from trauma. CSF is . | Chapter 5 The Nervous System Introduction The nervous system is truly remarkable. Every thought, feeling or action reveals its fascinating activity; consequently, malfunction of the nervous system can have a devastating effect on life. Compose a list of the conditions that you already know that affect the nervous system, add this to your portfolio The Nervous System The nervous system is divided into the central nervous system (CNS), comprising the brain itself and the spinal cord the peripheral nervous system (PNS), encompassing the cranial and spinal nerves. The CNS is an integrated command centre interpreting and responding to sensory impulses. The PNS is divided into sensory (afferent; carrying towards) and motor (efferent; carrying away) divisions. The Brain The brain has the consistency of a soft-boiled egg, the wrinkled appearance of a walnut and no moving parts. It is housed and protected by the skull, or cranium. The brain weighs approximately 1500g and contains more .
