Germ Layer Development

General Ectoderm

General Ectoderm

Epidermis of Skin

Enamel of Teeth

Inner Ear

Adenohypophysis

Parotid Gland

Mammary Gland

Lower Anal Canal

(below pectinate line)

Germ Layer Development

Neuroectoderm

Neuroectoderm

CNS

All neurons with cell bodies in CNS

Retina & CN II

Neurohypophysis

Astrocytes

Oligodendrocytes

Germ Layer Development

Neural Crest

(Ectoderm)

Neural Crest

Melanocytes

Cartilage/Bone of Head developed from pharyngeal arches

C cells of Thyroid Gland

Aorticopulmonary septum

Endocardial Cushions

Odontoblasts

Adrenal Medulla

PNS:

Sensory/Motor Ganglia

Schwann Cells

Germ Layer Development

Mesoderm

Mesoderm

*All Muscles, except pupil dilators*

Muscle Tissue

Connective Tissue

Bone

Cardiovascular

Lymphatic

*Spleen

Kidney

Gonads

*Adrenal Cortex

Germ Layer Development

Endoderm

Endoderm

A.Lining Epithelium of:

GI

Respiratory

Urinary

Reproductive

B. Pharyngeal Pouches

C. Parenchyma of:

Liver

Pancreas

Submandibular gland

Sublingual Gland

D. Thyroid Gland - Follicles

(not C-cells, neural crest)

Neural Development

What does the Notochord induce? 

What does the Notochord become in Adults?

Notochord induces ectoderm to differentiate into neuroectoderm and form the neural plate

Neural Plate → neural tube and neural crest cells

Notochord becomes nucleus pulposus of intervertebral disks in adults

Neural Development

What does the Basal Plate develop into?

What does the Alar Plate develop into?

Basal Plate → Motor

Alar Plate → Sensory

Embryology

What are causes of Polyhydramnios?

Anencephaly (↑ α-fetoprotein)

TE Fistula

Embryology

How does the Brain Develop?

Forbrain → Telencephalon + Diencephalon

Midbrain → Mesencephalon

Hindbrain → Metencephalon + Myelencephalon

Telencephalon → Cerebral Hemispheres

Diencephalon → Thalamus

Mesencephalon → Midbrain

Metencephalon → Pons + Cerebellum

Myelencephalon → Medulla

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Embryology

1. Where does most of the Basal Ganglia develop from?

2. Where does the Optic Nerve and Cup develop from?

3. What are the 4 Thalamic subdivisions that the diencephalon gives rise to?

4. Where does the posterior lobe of the pituitary develope from?

1. Telencephalon

2. Outgrowths of Diencephalon

3. Thalamus, Hypothalamus, Epithalamus, Subthalamus

4. Outgrowth of the Hypothalamus

Spinal Cord

What Tract does descending voluntary movement of contralateral limbs travel?

Lateral Corticospinal Tract

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Spinal Cord Lesions

Where would a lesion be with symptoms of:

Spastic Paralysis

Hyperreflexia

+ Babinski

↑ muscle tone

muscle weakness

Corticospinal Tract

Upper Motor Neuron Lesion

Above Medulla: Contralateral

Below Medulla: Ipsilatera

Spinal Cord Lesions

Where would a lesion be located with these symptoms:

Flaccid Paralysis

Areflexia

No Babinski

Fasiculations

↓ muscle tone

Coritcospinal Tract

Lower Motor Neuron Lesion

Always Ipsilateral

Spinal Cord

What tract carries ascending pain and temperature sensation?

Spinothalamic Tract

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Spinal Cord Lesions

Where would a lesion be with Loss of Pain and Temperature sensation?

Spinothalamic Tract

Contralateral to the affected side

Spinal Cord Lesions

What Spinal Tract Deccusates in the Ventral White Commissure?

Spinal Cord Lesions

What Spinal Tract carries ascending pressure, vibration, touch, and proprioceptive sensation?

Dorsal Column

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Spinal Cord

What parts of the Dorsal columns are associated with the:

Upper Body, Extremities

Lower Body, Extremities

Cuneatus = Arms

Gracilis = Legs

Spinal Cord Tracts

Locate these structures and what would happen if a lesion were to occur at it:

Dorsal Columns:

Cuneatus

Gracilis

Corticospinal Tract

Spinothalamic Tract

White Commissure

Spinal Cord Lesions

Cord Lesions between what vertebral bodies with include Horner's syndrome and both upper and lower limbs?

Spinal Cord Lesions

Cord Lesions below T1 will involve what parts of the body?

Trunk and Lower Limbs

Spinal Cord Lesions

What diseases cause Lower motor neuron lesions only, due to:

destruction of Anterior horns → Flaccid Paralysis.

Poliomyelitis

Werdnig-Hoffmann Disease

Spinal Cord Lesions

What Disease has combined upper and lower motor neuron deficits with No sensory deficits?

Lower Limb - UMN

Upper Limb - LMN

ALS

Spinal Cord Lesions

What syndrome causes Bilateral loss of pain and temperature sensation in upper extremities with preservations of touch and sensation?

Syringomyelia

Most Common at C8-T1

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Spinal Cord Lesions

What Disease and Syndrome are associated with:

+Rhomberg Sign

Sensory Ataxia

High Stepping Gait

Polyuria

Shooting Pains

Parastesias in Lower Limbs

3º Syphilis

Tabes Dorsalis

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Spinal Cord Lesions

What Syndrome presents with:

(1) Ipsilateral at the level of the lesion:

Loss of all sensation

Flaccid paralysis

(2) Ipsilateral Below the Lesion:

Spasticity

Loss of tactile, vibration, proprioception

(3) Contralateral below the Lesion:

Loss of Pain and Temperature

Brown-Sequard Syndrome

(If lesion occurs above T1, presents with Horner's Syndrome and Both Limbs)

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Brain Stem Lesions

What 3 Cranial Nerve Deficits will be Medial Brain Stem Lesions?

III, VI, XII

Brain Stem Lesions

What CN Lesion and Position in the Brain Stem causes:

Diplopia

Eye points down and out - lateral strabismus

ptosis

Fixed Dilated Pupil

CN III

Medial Brain Stem

Midbrain

Artery associated: PCA

Brain Stem Lesion

CN Lesion and Brain Stem Position associated with:

Diplopia

Eye Points Nasal - Medial Strabismus

CN VI

Medial Brain Stem

Lower Pons

Associated artery: Paramedian

Brain Stem Lesion

CN Lesion and Position in Brain Stem associated with:

Mandibular Deviation

CN V

Lateral Brain Stem

Upper Pons

Associated artery: Superior Cerebellar

Brain Stem Lesions

CN Lesion and Postion in Brain Stem assoicated with:

Facial Muscle Paralysis

Hyperacusis

Loss of secretions from ipsilateral lacrimal, submandibular, and sublingual glands

CN VII

Lateral Brain Stem

Lower Pons

associated artery: AICA