Are you going to fight or flee?

Gatlin period 1

Group 2

Cerebral Cortex & Somatic pathways

Motor & Sensory

-layer of the brain often referred to as gray matter.

-Pathways that transport nerves to and from the brain.

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The cerebral ______ is divided into right and left hemispheres. It encompasses about ______ of the brain mass and lies over and around most of the structures of the brain. It is the most highly developed part of the human _______and is responsible for thinking, perceiving, producing and understanding language. It is also the most recent structure in the history of brain ______.

Cortex Sensory Evolution

Motor Brain Two-Thirds

Afferent pathways: Sensory information coming from the _________ receptors through peripheral nerves to the spinal cord and on to the brain. Efferent pathways. _______commands coming from the brain and spinal cord, through peripheral nerves to effecter organs.

Phrase Word Match

Mytosomes Puzzle!

Answer: skeletal muscles innervated by one or more given spinal nerves (8)

Dermatomes Puzzle!Answer: skin surface areas supplied by a single spinal nerve (8)

Nerve Plexuses Puzzle!Answer: intersecting and communicating spinal nerves (8)

Meninges

� meninges, three membranous envelopes—pia mater, arachnoid, and dura mater—that surround the brain and spinal cord. Cerebrospinal fluid fills the ventricles of the brain and the space between the pia mater and the arachnoid. The primary function of the meninges and of the cerebrospinal fluid is to protect the central nervous system. (10)

Pia Mater

� The pia mater is the meningeal envelope that firmly adheres to the surface of the brain and spinal cord. It is a very thin membrane composed of fibrous tissue covered on its outer surface by a sheet of flat cells thought to be impermeable to fluid. The pia mater is pierced by blood vessels that travel to the brain and spinal cord. (10)

Arachnoid� Over the pia mater and separated from it by a space called the subarachnoid space is the arachnoid, a thin, transparent membrane. It is composed of fibrous tissue and, like the pia mater, is covered by flat cells also thought to be impermeable to fluid. In the region of the brain, particularly, a large number of fine filaments called arachnoid trabeculae pass from the arachnoid through the subarachnoid space to blend with the tissue of the pia mater. The arachnoid trabeculae are embryologic remnants of the common origin of the arachnoid and pia mater, and they have the frail structure characteristic of these two of the meninges. The pia mater and arachnoid together are called the leptomeninges. (10)

Dura Mater� The outermost of the three meninges is the dura mater (or pachymeninx), a strong, thick, and dense membrane. It is composed of dense fibrous tissue, and its inner surface is covered by flattened cells like those present on the surfaces of the pia mater and arachnoid. The dura mater is a sac that envelops the arachnoid and has been modified to serve several functions. The duramater surrounds and supports the large venous channels (dural sinuses) carrying blood from the brain toward the heart.(10)

CSF

� Cerebrospinal fluid (CSF) is a clear, colorless liquid that bathes the brain and spinal cord. While the primary function of CSF is to cushion the brain within the skull and serve as a shock absorber for the central nervous system, CSF also circulates nutrients and chemicals filtered from the blood and removes waste products from the brain. Examining the fluid can be useful in diagnosing many diseases of the nervous system, including MS(11)

Spinal CordThe Spinal Cord is connected to the brain and is about the diameter of a human finger. From the brain the spinal cord descends down the middle of the back and is surrounded and protected by the bony vertebral column. The spinal cord is surrounded by a clear fluid called Cerebral Spinal Fluid (CSF), that acts as a cushion to protect the delicate nerve tissues against damage from banging against the inside of the vertebrae. The nerves which exit the spinal cord in the mid and lower section of the back, control the trunk and legs, as well as bladder, bowel and sexual function. The nerves which carry information from the brain to muscles are called Motor Neurones. The nerves which carry information from the body back to the brain are called Sensory Neurones. Sensory Neurones carry information to the brain about skin temperature, touch, pain and joint position.The brain and spinal cord are referred to as the Central Nervous System, whilst the nerves connecting the spinal cord to the body are referred to as the Peripheral Nervous System.(12)

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Across2. purpose includes slowing down your heartbeat, lowering your blood pressure, and increasing blood flow to your skin.Down1. function is the mobilization of the body’s nervous system due to fight or flight response.3. Functions to regulate the basic visceral (organ) processes needed for the maintenance of normal bodily functions.

Peripheral Nervous System