{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

3 - structure of the nervous system

3 - structure of the nervous system - Basic Features of the...

Info icon This preview shows pages 1–5. Sign up to view the full content.

View Full Document Right Arrow Icon
Basic Features of the Nervous System 20:46 Neuraxis: An imaginary line drawn through the spinal cord up to the front of the  brain Anterior: The front end Posterior: The tail Rostral: Toward the beak Caudal: Toward the tail  Dorsal: The top of the head and the back  Ventral: Front Lateral: Toward the side Medial: Toward the middle Ipsilateral: Structures on the same side of the body Contralateral: Structures on opposite sides of the body We can slice the nervous system in three ways Cross sections/frontal sections: Transversely Horizontal sections: Parallel to the ground Sagittal sections: Perpendicular to the ground and parallel to the neuraxis o Midsagittal plane: Divides the brain into two symmetrical halves An Overview The brain receives approximately 20% of the blood flow from the heart, and it  receives it continuously  Meninges The protective sheaths around the brain and spinal cord
Image of page 1

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
o Consist of three layers Dura mater: The outer layer is thick, tough, and flexible but  unstretchable Arachnoid membrane: The middle layer is soft and spongy and lies  beneath the dura mater Pia mater: Closely attached to the brain and spinal cord and following  every surface convolution  Subarachnoid space: Gap between the pia mater and arachnoids  membrane Filled with cerebrospinal fluid (CSF) The PNS is covered with two layers of meninges The Ventricular System and Production of CSF The intact brain within a living human is well protected  o It floats in a bath of CSF contained within the subarachnoid brain Ventricles: Hollow, interconnected chambers o Lateral ventricles: The largest chambers o Third ventricle: Located at the midline of the brain Its walls divide the surrounding part of the brain into symmetrical  halves  o Cerebral aqueduct: Connects the third ventricle to the fourth ventricle  Choroid plexus: Protrudes into all four ventricles  o CSF is produced continuously  Arachnoid granulations: Reabsorbs CSF into the blood supply o Superior sagittal sinus: A blood vessel that drains into the veins serving  the brain Occasionally, the flow of CSF is interrupted at some point in its route of  passage o Obstructive hydrocephalus: A condition in which all or some of the brain’s  ventricles are enlarged 
Image of page 2
The Central Nervous System 20:46 Development of the Central Nervous System
Image of page 3

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
The Central Nervous System 20:46 An Overview of Brain Development o Part of the ectoderm of the back of the embryo thickens and forms a plate Neural tube: Gives rise to the brain and spinal cord o
Image of page 4
Image of page 5
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern