BI302L.Lab_B.Presentation.pdf - BI 302L: Lab B Topic: Brain...

BI 302L: Lab B
Topic: Brain & Cranial Nerves
• B1. Gross Anatomy of
the Brain & Cranial Nerves
• B2. Sheep Brain Dissection
Textbook Material:
• Chapter 14 (Saladin)
Are you wearing appropriate attire?
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B1. Gross Anatomy of the Brain & Cranial Nerves
Objectives:
• Identify the major anatomical structures of the human brain.
• Know the major components of the telencephalon, diencephalon, mesencephalon,
metencephalon, and myelencephalon.
• Understand the structure & location of the meninges.
• Identify the ventricles and other structures associated with cerebrospinal fluid and
know the pattern of flow of cerebrospinal fluid.
• Know the cranial fossae of the skull and the respective part of the brain that each
houses.
• Know and identify all cranial nerves by name & number (diagrams, models, and
cadaver as appropriate); know the foramina by which each cranial nerve exits the
skull; and be able to identify foramina on a skull.
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B1. Gross Anatomy of the Brain & Cranial Nerves
Major Subdivisions (Encephalons) of the Brain:
• Telencephalon = Cerebrum
• Diencephalon = Thalamus, Hypothalamus, pituitary gland, Epithalamus (pineal),
mammillary bodies
• Mesencephalon = Midbrain
• Metencephalon = Pons & Cerebellum
• Myelencephalon = Medulla Oblongata
“Brain Stem”: This term is frequently used but is an imprecise term. In humans it is usually
described as including the medulla oblongata (myelencephalon), pons (part of
metencephalon), and midbrain (mesencephalon). In some definitions the cerebellum and
parts of the diencephalon are included. It is never described as including the telencephalon.
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Frontal lobe
Occipital lobe
Central
sulcus
Longitudinal fissure
Parietal lobe
Superior view
Parieto-occipital sulcus
Fissures:
• Longitudinal Fissure: separates
cerebral hemispheres.
• Transverse Fissure: separates
cerebrum from the cerebellum.
Sulci:
• Sulci (grooves) and gyri (ridges)
are found on the surface of the
cerebrum.
• Deeper (named) sulci separate
lobes of the cerebrum.
B1. Gross Anatomy of the Brain & Cranial Nerves
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Fig. 14.1
Lateral
sulcus
Transverse
Fissure

Parieto-occipital
sulcus
Lateral sulcus pulled apart
to expose insula lobe
Cerebrum (telencephalon): Lobes & sulci, lateral view
B1. Gross Anatomy of the Brain & Cranial Nerves
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Fig. 14.13
Central
sulcus
Insula
Temporal lobe
Lateral sulcus
Occipital lobe
Parietal lobe Frontal lobe

Corpus
callosum
Septum
pellucidum
Fornix
Cerebrum: Internal structures
Sagittal Section of brain
B1. Gross Anatomy of the Brain & Cranial Nerves
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Fig. 14.2
Parieto-
occipital
sulcus
Brain:
Gray matter
White matter
Fig. 14.5

B1. Gross Anatomy of the Brain & Cranial Nerves
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Frontal lobe
Temporal lobe
Infundibulum
Pons
Medulla
oblongata
Cerebellum
Spinal cord
External Structures:
On Inferior Surface of Brain.
• Mammillary bodies are the
predominant feature of the
diencephalon visible inferiorly.