# -*- coding: utf-8 -*-
from reportlab.lib.pagesizes import A4
from reportlab.lib.units import inch
from reportlab.lib.styles import getSampleStyleSheet, ParagraphStyle
from reportlab.lib.enums import TA_CENTER
from reportlab.platypus import SimpleDocTemplate, Paragraph, Spacer, ListFlowable, ListItem
from reportlab.lib import colors

doc = SimpleDocTemplate("/tmp/workspace/anatomy-tp1/Anatomy_TP1_Sept2025_Answers.pdf",
                         pagesize=A4, topMargin=0.6*inch, bottomMargin=0.6*inch,
                         leftMargin=0.7*inch, rightMargin=0.7*inch)

styles = getSampleStyleSheet()
title_style = ParagraphStyle('title2', parent=styles['Title'], fontSize=15, spaceAfter=4)
sub_style = ParagraphStyle('sub', parent=styles['Normal'], alignment=TA_CENTER, fontSize=10, textColor=colors.grey)
h1 = ParagraphStyle('h1', parent=styles['Heading1'], fontSize=13, spaceBefore=14, spaceAfter=6, textColor=colors.HexColor('#1a3c6e'))
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body = ParagraphStyle('body', parent=styles['Normal'], fontSize=10.3, leading=14, spaceAfter=6, alignment=4)
bullet = ParagraphStyle('bullet', parent=body, leftIndent=14, spaceAfter=3)
ans_label = ParagraphStyle('ans', parent=styles['Normal'], fontSize=10.3, leading=14, spaceAfter=4, textColor=colors.HexColor('#1a3c6e'))

story = []
story.append(Paragraph("MBBS Phase I (CBME) - ANATOMY PAPER I (RS-7)", title_style))
story.append(Paragraph("Q.P. Code: 5501  |  Sept 2025  |  Model Answers (Rajiv Gandhi University of Health Sciences, Karnataka)", sub_style))
story.append(Spacer(1, 14))

def para(text, style=body):
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def bullets(items, style=bullet):
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def heading(text):
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def subhead(text):
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# ---------------- LONG ESSAY ----------------
heading("LONG ESSAY (1 x 10 = 10 Marks)")
subhead("Q1. Describe the Shoulder (Glenohumeral) Joint")

subhead("a) Type of Joint")
para("Synovial joint of the ball-and-socket variety; it is a multiaxial joint permitting the widest range of movement of any joint in the body, at the expense of stability.")

subhead("b) Articulating Surfaces")
bullets([
 "Head of humerus - large, hemispherical, faces medially, superiorly and posteriorly; covered by hyaline cartilage.",
 "Glenoid cavity of scapula - shallow, pear-shaped depression on the lateral angle of scapula; deepened by the fibrocartilaginous glenoid labrum.",
 "There is marked disproportion between the large humeral head and the small, shallow glenoid cavity (only about a third of the head contacts the glenoid at any time) - this accounts for the great mobility but relative instability of the joint."
])

subhead("c) Ligaments")
bullets([
 "<b>Fibrous (articular) capsule</b> - loose and lax, attached to the margin of the glenoid cavity (outside the labrum) above and to the anatomical neck of the humerus below (extending onto the surgical neck medially, enclosing the intertubercular groove).",
 "<b>Glenohumeral ligaments</b> (superior, middle, inferior) - three capsular thickenings on the anterior aspect strengthening the capsule; the inferior glenohumeral ligament is the primary anterior stabiliser in abduction.",
 "<b>Coracohumeral ligament</b> - from the root of the coracoid process to the greater tubercle, reinforcing the capsule superiorly.",
 "<b>Transverse humeral ligament</b> - bridges the two tubercles, converting the intertubercular (bicipital) groove into a tunnel for the tendon of the long head of biceps.",
 "<b>Glenoid labrum</b> - fibrocartilaginous rim that deepens the glenoid cavity and gives attachment to the long head of biceps and triceps.",
 "<b>Coracoacromial ligament</b> (accessory) - spans the coracoid process to the acromion, forming the coracoacromial arch which protects the joint superiorly and limits abduction beyond the arch."
])

subhead("d) Movements and Muscles Producing Them")
bullets([
 "<b>Flexion</b> - pectoralis major (clavicular head), anterior fibres of deltoid, coracobrachialis, biceps brachii.",
 "<b>Extension</b> - latissimus dorsi, teres major, posterior fibres of deltoid, long head of triceps.",
 "<b>Abduction</b> - 0-15&deg;: supraspinatus initiates; 15-90&deg;: deltoid (middle fibres) is prime mover; beyond 90&deg;: trapezius and serratus anterior rotate the scapula to allow full overhead abduction (scapulohumeral rhythm).",
 "<b>Adduction</b> - pectoralis major, latissimus dorsi, teres major, coracobrachialis.",
 "<b>Medial (internal) rotation</b> - subscapularis, pectoralis major, latissimus dorsi, teres major, anterior deltoid.",
 "<b>Lateral (external) rotation</b> - infraspinatus, teres minor, posterior deltoid.",
 "The rotator cuff muscles - Supraspinatus, Infraspinatus, Teres minor, Subscapularis (SITS) - blend with the capsule and act as dynamic stabilisers of the joint throughout all movements."
])

subhead("e) Applied Anatomy")
bullets([
 "Shoulder is the most frequently dislocated large joint in the body because of the shallow glenoid, lax capsule and wide range of motion.",
 "<b>Anterior (subcoracoid) dislocation</b> is commonest (&gt;95%), typically from a fall on an abducted, externally rotated arm; it may injure the axillary nerve (loss of deltoid contraction, sensory loss over the 'regimental badge' area) and rarely the axillary artery.",
 "<b>Posterior dislocation</b> is rare and is classically associated with seizures or electric shock.",
 "Recurrent dislocation results from a Bankart lesion (labral/capsular tear) or a Hill-Sachs lesion (compression fracture of the postero-lateral humeral head).",
 "Rotator cuff tears (commonly supraspinatus) produce a painful arc of abduction; degeneration of the capsule causes adhesive capsulitis ('frozen shoulder')."
])

# ---------------- REASONING QUESTIONS ----------------
heading("REASONING QUESTIONS - Short Answer (5 x 3 = 15 Marks)")

subhead("Q2. Stab injury to the left side of the neck causing injury to the thoracic duct")
para("The thoracic duct ascends through the posterior mediastinum and, on reaching the root of the neck at the level of the C7 vertebra, arches laterally to the <b>left</b> side. In this arch it lies deep to the sternocleidomastoid, crossing behind the left common carotid artery, vagus nerve and internal jugular vein, and in front of the vertebral artery, thyrocervical trunk and phrenic nerve, before draining into the venous angle (junction of left subclavian and left internal jugular veins). Because this superficial cervical arch exists only on the left side, a stab wound in the lower part of the left side of the neck can lacerate the duct, causing leakage of chyle into the neck/pleural space (chylothorax). A similar wound on the right side does not injure the thoracic duct, since the right side is drained only by the much smaller right lymphatic duct.")

subhead("Q3. Posterior cricoarytenoid - the 'safety muscle' of the larynx")
para("The posterior cricoarytenoid is the <b>only abductor</b> of the vocal folds; all other intrinsic laryngeal muscles are adductors or tensors. Its contraction rotates the arytenoid cartilage so that the vocal process swings laterally, abducting the vocal cords and widening the rima glottidis to keep the airway patent during respiration. If this muscle is paralysed bilaterally (e.g. bilateral recurrent laryngeal nerve injury), the unopposed adductors pull the cords together, producing acute airway obstruction - a life-threatening emergency. Because it is the sole safeguard against glottic closure, it is called the 'safety muscle of the larynx'.")
para("<b>Nerve supply:</b> Recurrent laryngeal nerve (branch of the vagus, CN X) - which supplies all intrinsic muscles of the larynx except cricothyroid (supplied by the external laryngeal nerve, a branch of the superior laryngeal nerve).")

subhead("Q4. Long thoracic nerve injury and winging of scapula")
para("The long thoracic nerve (C5, C6, C7, from the roots of the brachial plexus) runs superficially on the outer surface of serratus anterior, making it vulnerable during axillary surgery (e.g. mastectomy with axillary clearance). Serratus anterior is the principal muscle that keeps the medial border and inferior angle of the scapula firmly applied to the thoracic wall, and it rotates the scapula to permit abduction of the arm above 90&deg;. Paralysis of serratus anterior following nerve injury removes this stabilising pull, so the medial border of the scapula lifts away from the chest wall and protrudes posteriorly - a 'winged scapula' - which becomes most obvious when the patient pushes against a wall with outstretched arms.")

subhead("Q5. Hilton's Law")
para("Hilton's law states that the nerve supplying a joint also supplies the muscles that move that joint and the skin covering the articular insertions of those muscles. In other words, a single nerve trunk innervates the joint, the muscles acting across it and the overlying skin at the muscle attachments. Clinically, this explains patterns of referred pain - disease or irritation of a joint may present as pain felt in the skin or muscles supplied by the same nerve (e.g. hip joint pathology referred as knee pain, since the obturator nerve supplies both the hip joint and the skin over the medial aspect of the knee/thigh).")

subhead("Q6. Charcot's artery as the 'artery of cerebral haemorrhage'")
para("Charcot's artery refers to the largest of the lateral (lenticulo-)striate branches of the middle cerebral artery. <b>Origin:</b> it arises from the middle cerebral artery (M1 segment), itself a terminal branch of the internal carotid artery. <b>Distribution:</b> it supplies the internal capsule (posterior limb), and the basal ganglia - caudate nucleus, putamen and globus pallidus. These lateral striate arteries arise almost at right angles from the MCA and pursue a long, straight, unsupported course through the substance of the brain with little branching to dissipate pressure; this makes them especially prone to rupture under raised intraluminal pressure (as in hypertension), making the basal ganglia/internal capsule the commonest site of hypertensive intracerebral haemorrhage - hence Charcot named this vessel the 'artery of cerebral haemorrhage'.")

story.append(Spacer(1, 6))

# ---------------- SHORT NOTES SET 1 ----------------
heading("SHORT NOTES (4 x 5 = 20 Marks)")

subhead("Q7. Hoarseness of voice after thyroid surgery")
para("<b>Nerve involved:</b> Recurrent laryngeal nerve (usually unilateral injury). <b>Why:</b> the recurrent laryngeal nerve ascends in the tracheo-oesophageal groove in close relation to the inferior thyroid artery and posterior aspect of the thyroid gland, and is at risk of being clamped, ligated or stretched while securing the inferior thyroid artery during thyroidectomy. As it supplies all intrinsic muscles of the larynx except cricothyroid, its injury paralyses the vocal cord (which comes to lie in the paramedian position), producing hoarseness; bilateral injury causes aphonia and airway obstruction requiring emergency tracheostomy.")
para("<b>Relations of the thyroid gland:</b>")
bullets([
 "Isthmus - anteriorly: sternohyoid, sternothyroid, skin and fascia; posteriorly: 2nd-4th tracheal rings.",
 "Anterolateral surface of lobes - sternothyroid, sternohyoid, superior belly of omohyoid, anterior border of sternocleidomastoid.",
 "Medial surface - larynx, trachea, pharynx, oesophagus, cricothyroid muscle with external laryngeal nerve, and the recurrent laryngeal nerve in the tracheo-oesophageal groove.",
 "Posterolateral surface - carotid sheath (common carotid artery, internal jugular vein, vagus nerve).",
 "Postero-medial - parathyroid glands and recurrent laryngeal nerve."
])

subhead("Q8. Oculomotor nerve (CN III) - origin, course, branches, distribution and applied anatomy")
bullets([
 "<b>Origin:</b> oculomotor nuclear complex in the midbrain (ventral to the cerebral aqueduct, at the level of the superior colliculus), including the parasympathetic Edinger-Westphal nucleus; fibres emerge through the interpeduncular fossa on the medial side of the crus cerebri.",
 "<b>Course:</b> passes between the posterior cerebral and superior cerebellar arteries, pierces the dura lateral to the posterior clinoid process, runs in the lateral wall of the cavernous sinus, and enters the orbit through the superior orbital fissure within the tendinous ring (annulus of Zinn), dividing into superior and inferior divisions.",
 "<b>Branches/Distribution:</b> superior division supplies superior rectus and levator palpebrae superioris; inferior division supplies medial rectus, inferior rectus and inferior oblique, and gives a parasympathetic branch to the ciliary ganglion, whose postganglionic fibres supply the sphincter pupillae and ciliaris muscle.",
 "<b>Applied anatomy:</b> a complete third nerve palsy produces ptosis, a divergent 'down-and-out' eye (unopposed lateral rectus and superior oblique), and a dilated, fixed pupil if the parasympathetic fibres are involved. Compressive lesions (e.g. posterior communicating artery aneurysm) affect the superficially placed pupillary fibres early ('pupil-involving' palsy), whereas ischaemic/diabetic microvascular palsy characteristically spares the pupil ('pupil-sparing' palsy) because the centrally placed fibres to the extraocular muscles are affected preferentially."
])

subhead("Q9. Right coronary artery occlusion")
para("<b>Surfaces of the heart:</b> sternocostal (anterior) surface, diaphragmatic (inferior) surface, left (pulmonary) surface, and the base (posterior surface, formed mainly by the left atrium).")
para("<b>Branches and area supplied by the right coronary artery (RCA):</b> arising from the right aortic sinus, it gives the SA nodal branch (in ~60% of individuals), right marginal artery, AV nodal branch, and (in the commoner 'right-dominant' pattern) continues as the posterior interventricular (descending) artery. It supplies the right atrium, right ventricle, the posterior one-third of the interventricular septum, and in right-dominant hearts, the diaphragmatic surface of the left ventricle; it also supplies the SA node and AV node in the majority of people - explaining why RCA occlusion commonly causes inferior wall myocardial infarction with conduction disturbances (sinus bradycardia, AV block).")

subhead("Q10. Seetha and Geetha - twinning")
para("<b>a) Type of twinning:</b> Since the twins 'look alike' (are identical), this is <b>monozygotic twinning</b> - arising from division of a single fertilised ovum (zygote), giving genetically identical offspring.")
para("<b>b) Types of twinning:</b>")
bullets([
 "<b>Dizygotic (fraternal) twins</b> - result from fertilisation of two separate ova by two different sperm; each has its own placenta, chorion and amnion (dichorionic, diamniotic); may be same or different sex.",
 "<b>Monozygotic (identical) twins</b> - from splitting of a single zygote; the type of membranes depends on the timing of splitting: split within 3 days (before morula stage) gives dichorionic diamniotic twins; split between day 4-8 (blastocyst, before amnion forms) gives monochorionic diamniotic twins (commonest type); split between day 8-13 (after amnion has formed) gives monochorionic monoamniotic twins; splitting after day 13 (after formation of the embryonic disc) results in incomplete separation and conjoined twins."
])
para("<b>c) Hazards of twinning:</b> prematurity and low birth weight, malpresentation and difficult labour, twin-to-twin transfusion syndrome (in monochorionic twins with shared placental vascular anastomoses), umbilical cord entanglement/knotting (monoamniotic twins), increased maternal complications such as pre-eclampsia, polyhydramnios and postpartum haemorrhage, higher perinatal morbidity/mortality, and conjoined twins in incomplete separation.")

story.append(Spacer(1, 6))

# ---------------- SHORT NOTES SET 2 ----------------
heading("SHORT NOTES (7 x 5 = 35 Marks)")

subhead("Q11. Pleural recesses and their importance")
bullets([
 "<b>Costodiaphragmatic recess</b> - between the costal and diaphragmatic pleura; the deepest and most dependent pleural recess, extending from the 6th to 8th rib in the midaxillary line. During quiet respiration the lung does not fully occupy it, but it expands into it on deep inspiration.",
 "<b>Costomediastinal recess</b> - between the costal and mediastinal pleura anteriorly; more prominent on the left side owing to the cardiac notch."
])
para("<b>Importance:</b> because the lung does not fill these recesses completely in quiet breathing, they act as potential spaces where fluid, blood, pus, or air can collect (pleural effusion, haemothorax, empyema, pneumothorax) - most notably in the costodiaphragmatic recess, which is the site of choice for pleural aspiration (thoracocentesis) and chest tube insertion, performed above the 8th/9th rib in the midaxillary/scapular line to avoid the neurovascular bundle and abdominal viscera.")

subhead("Q12. Parotid gland")
para("<b>External features:</b> the largest of the salivary glands, wedge/pyramidal in shape, occupying the retromandibular region between the ramus of the mandible anteriorly and the mastoid process/sternocleidomastoid posteriorly. It has superficial and deep parts connected by an isthmus, is enclosed in a tough parotid (investing) fascia, and its duct (Stensen's duct) emerges from the anterior border, crosses the masseter, turns medially to pierce the buccinator and opens into the oral vestibule opposite the crown of the upper second molar tooth.")
para("<b>Relations:</b>")
bullets([
 "Anterior - masseter muscle, ramus of mandible.",
 "Posterior - mastoid process, sternocleidomastoid, posterior belly of digastric, styloid process and its muscles.",
 "Superior - external acoustic meatus and the temporomandibular joint.",
 "Medial (deep) - the styloid apparatus separates it from the carotid sheath and the parapharyngeal space; the deep part may abut the pharyngeal wall."
])
para("<b>Contents within the gland</b> (superficial to deep): the facial nerve (CN VII) and its five terminal branches lie most superficially within the substance of the gland; the retromandibular vein lies in an intermediate plane; the external carotid artery lies deepest, dividing within the gland into the maxillary and superficial temporal arteries. Parotid lymph nodes are also embedded in the gland.")

subhead("Q13. Microscopy of sensory ganglion vs sympathetic ganglion")
bullets([
 "<b>Sensory (dorsal root / spinal) ganglion:</b> contains unipolar (pseudounipolar) neurons; the cell bodies are large, rounded, and arranged in clusters or rows towards the periphery of the ganglion, each surrounded by a distinct capsule of flattened satellite (capsular) cells; no true synapses occur here as these neurons simply relay impulses; nerve fibres running through the ganglion are predominantly myelinated.",
 "<b>Sympathetic (autonomic) ganglion:</b> contains multipolar neurons that are smaller, more irregular (spindle/stellate) in shape, and scattered irregularly (not in orderly rows) throughout the ganglion; the satellite cell capsule around each neuron is thin and incomplete; true synapses occur here between preganglionic and postganglionic neurons; postganglionic fibres leaving the ganglion are mostly unmyelinated (giving a grey appearance to the grey rami communicantes)."
])
para("<i>(Diagram: draw the DRG showing peripherally placed large round cell bodies in rows with a capsule of satellite cells and centrally running myelinated fibre bundles; draw the sympathetic ganglion showing smaller, irregularly scattered multipolar neurons with synaptic contacts and fine unmyelinated fibres coursing between them.)</i>")

subhead("Q14. Cavernous sinus")
bullets([
 "<b>Location:</b> a paired dural venous sinus situated on either side of the body of the sphenoid bone, extending from the superior orbital fissure anteriorly to the apex of the petrous temporal bone posteriorly.",
 "<b>Relations:</b> medially - pituitary gland and sphenoid air sinus; laterally - temporal lobe of the cerebrum; roof - diaphragma sellae; floor - junction of the body and greater wing of sphenoid.",
 "<b>Structures passing through:</b> in the lateral wall, from above downward - oculomotor nerve (III), trochlear nerve (IV), ophthalmic (V1) and maxillary (V2) divisions of the trigeminal nerve; within the substance of the sinus - the internal carotid artery (with its surrounding sympathetic plexus) and the abducent nerve (VI).",
 "<b>Tributaries (drainage into the sinus):</b> superior and inferior ophthalmic veins, superficial middle cerebral vein, sphenoparietal sinus, and central vein of the retina.",
 "<b>Communications:</b> with the opposite cavernous sinus via the intercavernous sinuses (forming the circular sinus around the pituitary); posteriorly via the superior petrosal sinus to the transverse sinus and via the inferior petrosal sinus to the internal jugular vein; also communicates with the pterygoid venous plexus through emissary veins passing via the foramen ovale and foramen lacerum."
])
para("<b>Applied anatomy:</b> infection from the 'dangerous area' of the face can spread via the ophthalmic veins to cause cavernous sinus thrombosis, presenting with proptosis, chemosis, and ophthalmoplegia from involvement of III, IV, VI and V1.")

subhead("Q15. Superior mediastinum - boundaries and contents")
para("<b>Boundaries:</b> anteriorly - manubrium sterni; posteriorly - bodies of T1-T4 vertebrae; superiorly - the thoracic inlet, continuous with the root of the neck; inferiorly - the transverse thoracic plane (plane of Ludwig), an imaginary plane from the sternal angle to the lower border of T4, separating it from the inferior mediastinum; laterally - mediastinal pleura of each side.")
para("<b>Contents (anterior to posterior):</b> thymus (or its remnant); the great veins - left and right brachiocephalic veins and the upper part of the superior vena cava; the arterial structures - arch of the aorta with its three branches (brachiocephalic trunk, left common carotid and left subclavian arteries); nerves - both phrenic nerves, both vagus nerves, the left recurrent laryngeal nerve, and the cardiac plexus; the trachea and oesophagus; the thoracic duct; and paratracheal/pretracheal lymph nodes.")

subhead("Q16. Tonsillar fossa - boundaries and blood supply of palatine tonsil")
para("<b>Boundaries of the tonsillar fossa</b> (in the lateral wall of the oropharynx): anteriorly - the palatoglossal fold (anterior pillar, containing palatoglossus muscle); posteriorly - the palatopharyngeal fold (posterior pillar, containing palatopharyngeus muscle); floor/bed - the superior constrictor muscle covered by the pharyngobasilar fascia, which separates the tonsil from the facial artery and its branches lying outside it; superiorly - continuous with the soft palate.")
para("<b>Blood supply of the palatine tonsil:</b> the chief artery is the <b>tonsillar branch of the facial artery</b>, which pierces the superior constrictor to reach the tonsil. Additional contributing vessels form the 'tonsillar circle of arteries': the ascending palatine artery (branch of facial artery), dorsal lingual branches of the lingual artery, the ascending pharyngeal artery (from the external carotid), the descending/greater palatine branch of the maxillary artery, and the artery of the pterygoid canal. Venous drainage is via the paratonsillar vein into the pharyngeal venous plexus/facial vein.")

subhead("Q17. Importance of cadavers in medical education")
bullets([
 "Provides a true three-dimensional appreciation of anatomical structures, their spatial relationships and normal variations that cannot be fully learnt from books, models or digital/virtual dissection alone.",
 "Allows students to develop dissection, hand-eye coordination and procedural skills, and to appreciate real tissue planes and consistency before operating on living patients.",
 "Forms the foundation for surgical training, development of new operative techniques, and research (e.g. testing surgical instruments/implants).",
 "First exposure to human mortality in a controlled setting, fostering professionalism, respect for the human body, empathy and ethical grounding through interaction with body donors.",
 "Cadaveric variations prepare students for the anatomical variability encountered in real clinical and radiological practice.",
 "Remains the gold standard for teaching gross anatomy, complementing (not replaced by) prosection, models, imaging and virtual/digital tools."
])

story.append(Spacer(1, 6))

# ---------------- MCQ ----------------
heading("MULTIPLE CHOICE QUESTIONS - Scenario Based (20 x 1 = 20 Marks)")

mcqs = [
 ("18(i)", "A young man with headache, forgetfulness and a diagnosed glioma - which cell forms the myelin sheath around CNS axons?",
  "<b>Oligodendrocytes</b> - these CNS glial cells wrap myelin around multiple axons (the PNS equivalent is the Schwann cell)."),
 ("18(ii)", "Which of the following is NOT a neuron: Schwann cells / Basket cells / Stellate cells / Horizontal cells?",
  "<b>Schwann cells</b> - these are peripheral glial (supporting) cells, not neurons. Basket cells and stellate cells are cerebellar interneurons, and horizontal cells are retinal interneurons - all true neurons."),
 ("19(i)", "Pregnancy tests detect which substance in maternal urine?",
  "<b>Human chorionic gonadotrophin (hCG)</b> - secreted by syncytiotrophoblast from soon after implantation."),
 ("19(ii)", "Where does sperm capacitation occur?",
  "<b>Female genital tract</b> (uterus and uterine tube) - capacitation cannot occur in vitro without added factors, hence its physiological site is within the female reproductive tract."),
 ("20(i)", "Elbow struck on inner side -> tingling/numbness in ring and little finger. Nerve involved?",
  "<b>Ulnar nerve</b> - injured as it passes superficially behind the medial epicondyle of the humerus ('funny bone')."),
 ("20(ii)", "Sign of chronic ulnar nerve compression at the elbow (cubital tunnel syndrome)?",
  "<b>Clawing of the 4th and 5th digits</b> - due to paralysis of the medial two lumbricals with unopposed action of extensor digitorum and long flexors ('ulnar claw hand')."),
 ("21(i)", "Preferred vein for IV injection in the cubital fossa?",
  "<b>Median cubital vein</b> - large, superficial, relatively fixed and less painful to access."),
 ("21(ii)", "Structure separating this vein from the underlying brachial artery?",
  "<b>Bicipital aponeurosis</b> - a fibrous expansion from the biceps tendon that protects the brachial artery and median nerve deep to the median cubital vein."),
 ("22(i)", "Number of normal anatomical constrictions in the oesophagus?",
  "<b>Three</b> - at (1) the pharyngo-oesophageal junction (cricopharyngeus, ~15 cm from incisors - narrowest), (2) the aortic arch/left bronchus crossing (~22-27 cm), and (3) the diaphragmatic hiatus (~38-40 cm)."),
 ("22(ii)", "Structure causing the 2nd oesophageal constriction?",
  "<b>Arch of the aorta</b> - as it crosses the left side of the oesophagus (the left principal bronchus produces an immediately adjacent, sometimes separately described, indentation just below this level)."),
 ("23(i)", "Boxer with a blow to the side of the head develops extradural haematoma - artery most likely ruptured?",
  "<b>Middle meningeal artery</b> - classically torn where it grooves/pierces the thin squamous part of the temporal bone at the pterion."),
 ("23(ii)", "This artery enters the skull through which foramen?",
  "<b>Foramen spinosum</b> - in the greater wing of the sphenoid, just posteromedial to foramen ovale."),
 ("24(i)", "'Ganglion of hay fever' involved in allergic rhinitis?",
  "<b>Pterygopalatine ganglion</b> - its parasympathetic secretomotor fibres (via the nerve of the pterygoid canal) supply the nasal mucosa, and its overactivity underlies allergic rhinitic symptoms."),
 ("24(ii)", "Infraorbital nerve is a continuation of which nerve?",
  "<b>Maxillary nerve (V2)</b> - the infraorbital nerve is its direct continuation after it traverses the infraorbital groove/canal."),
 ("25(i)", "Type of synovial joint the TMJ represents?",
  "<b>Bicondylar joint</b> - an atypical synovial joint divided by an articular disc into upper (gliding) and lower (hinge) compartments."),
 ("25(ii)", "The articular disc of the TMJ blends with the tendon of which muscle?",
  "<b>Lateral pterygoid</b> - part of its tendon inserts into the anterior margin of the articular disc as well as the pterygoid fovea of the mandible."),
 ("26(i)", "Area of the brain crucial for processing visual information (relevant in posterior cerebral artery territory)?",
  "<b>Occipital lobe</b> - contains the primary visual cortex (around the calcarine sulcus), supplied by the posterior cerebral artery."),
 ("26(ii)", "The prefrontal cortex, responsible for planning and decision-making, is located in which lobe?",
  "<b>Frontal lobe</b> - the prefrontal cortex occupies the anterior part of the frontal lobe."),
 ("27(i)", "Lumbar puncture in an adult is performed between which vertebral levels?",
  "<b>L3-L4</b> (the L4-L5 space is also an acceptable/commonly used alternative) - chosen because the spinal cord (conus medullaris) ends at the L1-L2 level in adults, so a needle introduced below this is safely within the lumbar cistern of CSF, below the level of the spinal cord."),
 ("27(ii)", "The spinal dura mater extends down to the lower border of which vertebra?",
  "<b>S2</b> - the dural sac (and subarachnoid space) terminates at the level of the second sacral vertebra, beyond which the filum terminale continues alone to the coccyx."),
]

for num, stem, ans in mcqs:
    story.append(Paragraph(f"<b>{num}.</b> {stem}", ans_label))
    para(ans)

doc.build(story)
print("PDF created")