Chapter 10 _Brain and Cranial Nerves

Chapter 10 _Brain and Cranial Nerves - The Brain Divided...

Info iconThis preview shows pages 1–4. Sign up to view the full content.

View Full Document Right Arrow Icon
1 Chapter 10: The Brain & Cranial Nerves The Brain Divided into 4 distinct areas: Cerebral hemispheres (Cerebrum) Diencephalon Brain Stem Cerebellum Protected by the: Skull Meninges CSF Blood-brain barrier Protective Structures of the CNS: The Meninges The Meninges Dura Mater : double-layered cartilaginous membrane Periosteal layer : attached to surface of the skull Meningeal layer: outer covering of the brain Dural Sinuses/Venous channels : separations between the 2 layers in which blood from nervous tissue is drained The Meninges Arachnoid: middle Layer Loosely attached to the pia mater by web-like fibers Provides a space for the movement of CSF between the 2 membranes Pia Mater: innermost layer Attached to the brain & spinal cord Carries the brain’s blood supply Protective Structures of the CNS: Cerebrospinal Fluid (CSF) Functions: Protects the CNS Cushions shocks Carries nutrients to cells Transports waste products from cells Drains into the subarachnoid space returned to blood circulation via the arachnoid villi
Background image of page 1

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

View Full DocumentRight Arrow Icon
2 4 brain ventricles (spaces within the brain) Choroid Plexus : vascular network in each ventricle Brain Ventricles 2 lateral ventricles in the cerebral hemispheres largest of the ventricles have “horns” which extend into the cerebrum communicate with the 3 rd ventricle by a foramina 3 rd ventricle is surrounded by the diencephalon 4 th ventricle lies between brain stem Cerebral aqueduct connects the 3 rd th ventricles Flow of CSF in the Brain Choroid plexus subarachnoid space blood through the arachnoid villi in the dural sinuses Black arrows = CSF flow White arrows = blood flow Protective Structures of the CNS: The Blood-Brain Barrier Includes capillaries with tight junctions Excludes many potentially harmful substances, but some substances can get through to the brain, such as: Respiratory gases Alcohol Nicotine Anesthesia Organization of the Brain (Table 10-1) Sagital section
Background image of page 2
3 Cerebrum Largest, top part of the brain 2 cerebral hemispheres, each subdivided into 4 lobes, named after the overlying bones Longitudinal fissure separates the cerebral hemispheres down the middle, front to back Cerebrum: Cerebral Cortex Outer layer of gray matter made up of neuron cell bodies Most highly evolved part of brain responsible for higher level functioning e.g. memory, reasoning, conscious thoughts…etc. Arranged into folds:
Background image of page 3

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

View Full DocumentRight Arrow Icon
Image of page 4
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 8

Chapter 10 _Brain and Cranial Nerves - The Brain Divided...

This preview shows document pages 1 - 4. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online