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Here are complete answers to all 10 short answer questions:

1. Histological Diagram of a Large-Sized (Elastic) Artery

A large/elastic artery (e.g. aorta, common carotid) has three tunics:
LayerKey Features
Tunica IntimaSimple squamous endothelium + thin subendothelial connective tissue + internal elastic lamina (may be indistinct)
Tunica MediaThickest layer; 40-70 concentric elastic lamellae (fenestrated sheets) alternating with smooth muscle cells and collagen - this is the hallmark of a large/elastic artery
Tunica AdventitiaCollagen + fibroblasts + vasa vasorum + nervi vasorum; no prominent external elastic lamina
The defining characteristic is the thick media packed with elastic lamellae (demonstrated by pararosaniline-toluidine blue or Verhoeff stain), allowing the vessel to store and release energy with each cardiac cycle (Windkessel effect). - Fuster & Hurst's The Heart, 15th Ed.

2. Arteries Supplying the Suprarenal (Adrenal) Gland

Each adrenal gland receives blood from three arteries:
  1. Superior suprarenal artery - branch of the inferior phrenic artery
  2. Middle suprarenal artery - branch directly from the abdominal aorta
  3. Inferior suprarenal artery - branch of the renal artery
Venous drainage is via a single suprarenal vein: right drains into the IVC; left drains into the left renal vein. - Gray's Anatomy for Students; Histology: A Text and Atlas

3. Deep Flexors of the Forearm

The deep flexor compartment of the forearm contains three muscles:
  1. Flexor digitorum profundus (FDP) - flexes the DIP joints of fingers 2-5
  • Medial half (ring & little): innervated by the ulnar nerve
  • Lateral half (index & middle): innervated by the anterior interosseous nerve (branch of median)
  1. Flexor pollicis longus (FPL) - flexes the IP joint of the thumb; innervated by the anterior interosseous nerve
  2. Pronator quadratus - pronates the forearm; innervated by the anterior interosseous nerve

4. Parts of the Brain Stem

The brainstem has three parts (rostral to caudal):
  1. Midbrain (Mesencephalon) - contains cerebral peduncles, corpora quadrigemina (superior & inferior colliculi), CN III & IV nuclei
  2. Pons - connects cerebellum to brainstem; contains CN V, VI, VII, VIII nuclei; middle cerebellar peduncles
  3. Medulla oblongata - contains vital centres (cardiac, respiratory, vasomotor); CN IX, X, XI, XII nuclei; pyramidal decussation
(Some texts include the diencephalon as the 4th part, but in standard clinical usage, brainstem = midbrain + pons + medulla.) - Gray's Anatomy for Students; Neuroanatomy through Clinical Cases, 3rd Ed.

5. Bones of the Middle Ear

There are three ossicles (the smallest bones in the human body):
  1. Malleus (hammer) - attached to the tympanic membrane (eardrum); has a head, neck, handle (manubrium), and two processes
  2. Incus (anvil) - articulates with malleus laterally and stapes medially; has a body, short crus, and long crus
  3. Stapes (stirrup) - footplate sits in the oval window of the inner ear
They form an ossicular chain transmitting vibrations from the tympanic membrane to the oval window (amplifying sound ~22x). - Gray's Anatomy for Students; Histology: A Text and Atlas

6. Intrinsic Muscle Groups of the Tongue

The intrinsic muscles are confined entirely within the tongue (no bony attachment) and change the shape of the tongue. They run in three planes:
  1. Superior longitudinal - shortens tongue, curls tip upward
  2. Inferior longitudinal - shortens tongue, curls tip downward
  3. Transverse - narrows and elongates the tongue
  4. Vertical - flattens and widens the tongue
All intrinsic tongue muscles are innervated by the hypoglossal nerve (CN XII). - Color Atlas of Human Anatomy Vol. 2; Scott-Brown's Otorhinolaryngology

7. Nerve Supply of Extra-ocular Muscles

NerveMuscles Supplied
Oculomotor (CN III)Superior rectus, inferior rectus, medial rectus, inferior oblique, levator palpebrae superioris
Trochlear (CN IV)Superior oblique ("SO4")
Abducens (CN VI)Lateral rectus ("LR6")
Mnemonic: LR6SO4 - Lateral Rectus = CN VI, Superior Oblique = CN IV, all the rest = CN III.
  • Grainger & Allison's Diagnostic Radiology

8. Contents of the Cubital Fossa

The cubital fossa is a triangular depression anterior to the elbow. Contents from lateral to medial (mnemonic: TAN or MABEL):
  1. Tendon of biceps brachii - most lateral palpable structure
  2. Brachial artery - bifurcates into radial and ulnar arteries at the apex
  3. Median nerve - most medial
Additionally:
  • Radial nerve (and its deep branch) runs in the lateral groove between brachioradialis and brachialis (sometimes listed as a content)
  • The bicipital aponeurosis covers and protects the brachial artery and median nerve anteriorly
  • Median cubital vein lies superficially in the roof
  • Gray's Anatomy for Students

9. Three Derivatives of Neural Crest

Neural crest cells are multipotent migratory cells that give rise to a remarkably diverse array of structures:
  1. Peripheral nervous system - dorsal root ganglia (sensory neurons), autonomic ganglia, cranial nerve ganglia (V, VII, IX, X), Schwann cells
  2. Chromaffin cells of the adrenal medulla (and other neuroendocrine cells - APUD cells)
  3. Craniofacial structures - facial/skull bones, cartilage, teeth (odontoblasts), dermis of face
Other derivatives include: melanocytes, cardiac septa (aorticopulmonary septum), enteric nervous system (Meissner's and Auerbach's plexuses), meninges (pia and arachnoid), and smooth muscle of great vessels. - The Developing Human (Moore); Histology: A Text and Atlas

10. Branches of the Tibial Nerve in the Popliteal Fossa

The tibial nerve is the larger terminal branch of the sciatic nerve. Within the popliteal fossa it gives off:
  1. Muscular branches - to the two heads of gastrocnemius, soleus, plantaris, and popliteus
  2. Sural nerve (medial sural cutaneous nerve) - joins the common fibular's peroneal communicating branch to form the sural nerve; supplies skin of the posterior leg and lateral foot
  3. Articular branches - to the knee joint (superior medial, middle, inferior medial genicular contributions)
  4. Tibial anastomotic branch - joins the common fibular anastomotic branch to form the sural nerve
The tibial nerve then exits the popliteal fossa inferiorly between the two heads of gastrocnemius to enter the posterior leg. - Campbell's Operative Orthopaedics, 15th Ed.; Gray's Anatomy for Students
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