FINAL EXAM PREP

The Human Body: An Orientation

Anatomical Position

The anatomical position is a standardized posture used to describe locations and relationships of body parts. It is essential for clear communication in anatomy.

• Stand erect with feet flat, eyes facing forward, toes pointing forward.

• Palms anteriorly with thumbs away from the body.

• Right and left refer to the patient's or cadaver's right and left.

Tissues and the Integumentary System

Dermis

The dermis is the connective tissue layer beneath the epidermis, providing strength, flexibility, and housing blood vessels and nerves.

• Rich nerve and blood supply: Contains about 5% of all blood in the body.

• Vascular plexuses:

  • Dermal plexus (between dermis and subcutaneous tissue)

  • Subpapillary plexus (below dermal papillae)

• Temperature regulation:

  • Hot: Dermal vessels engorge, radiating heat away.

  • Cold: Vessels constrict, shunting blood to internal organs.

Bones and Skeletal Tissues

Bone Formation: Endochondral Ossification

Endochondral ossification is the process by which most bones are formed from a cartilage model.

• All bones except some skull and clavicle bones form this way.

• Bones are first modeled in hyaline cartilage.

• Formation continues until early adulthood.

Overview of Skull

• Cranial bones (neurocranium): Form the bony case of the brain.

• Facial bones (viscerocranium): Form the anterior aspect of the cranium.

Temporal Bones

• Squamous part: Forms part of the zygomatic arch.

• Tympanic part: External ear canal.

• Mastoid process: Site for neck muscle attachment.

• Petrous part: Houses middle and internal ear cavities.

• Mandibular fossa: Receives mandibular condyle, forming the temporomandibular joint (TMJ).

Foramina of the Temporal Bone

• Jugular foramen: Passage for internal jugular vein and cranial nerves IX, X, XI.

• Carotid canal: Internal carotid artery passes through.

• Internal acoustic meatus: Transmits cranial nerves VII, VIII.

General Structure of Vertebra

• Body: Size increases from cervical to lumbar.

• Vertebral arch, vertebral foramen, spinous process, transverse process, superior and inferior articular processes.

• Intervertebral foramina: Passage for spinal nerves.

• Anterior and posterior longitudinal ligaments: Stabilize vertebral column.

Upper Limb

• Arm: Humerus

• Forearm: Ulna and radius

• Hand: Carpal bones, metacarpal bones, phalanges

Pelvic Structure and Childbearing

• Bony pelvis:

  • False (greater) pelvis: Bounded by iliac bones.

  • True (lesser) pelvis: Inferior to pelvic brim, contains pelvic organs.

• Pelvic brim: Arcuate line of iliac bone, pectineal line of pubis, sacral alae, sacral promontory.

Muscle Tissue and Muscles of the Body

Structural Organization of Muscle

• Muscle: Organ containing connective tissue, blood vessels, nerves.

• Fascicle: Bundle of muscle fibers.

• Muscle fiber: Contains myofibrils, which are made of myofilaments (actin and myosin).

Muscles of Facial Expression

• Located in face and scalp, thin and variable in shape.

• Often insert into skin, not bones.

• Innervated by CN VII, the facial nerve.

Trapezius

• Attaches pectoral girdle to trunk; elevates, depresses, retracts, and rotates scapula.

• Origin: Occipital bone, ligamentum nuchae, spinous process of C7-T12.

• Insertion: Clavicle, acromion, spine of scapula.

• Innervated by CN XI.

Pectoralis Major

• Origin: Clavicular head, sternocostal head.

• Insertion: Intertubercular sulcus of humerus.

• Actions: Adducts, medially rotates, flexes (clavicular head), and extends (sternocostal head) the humerus.

Brachialis

• Origin: Anterior surface of distal humerus.

• Insertion: Ulna.

• Action: Flexes forearm in all positions; unaffected by pronation or supination.

Fundamentals of the Nervous System and Nervous Tissue

Neuron

• Nerve cell: Specialized for conducting nerve impulses.

• Longevity: Can live and function for a lifetime (100+ years).

• Do not divide: Fetal neurons lose ability to undergo mitosis (except neural stem cells).

• High metabolic rate: Require abundant oxygen and glucose.

The Central Nervous System

Midbrain

• Cerebral aqueduct: Central cavity of midbrain.

• Tectum: Roof of midbrain.

• Cerebral peduncles: Contain pyramidal tracts.

• Superior cerebellar peduncles: Connect midbrain to cerebellum.

• Cranial nerves III, IV originate here.

Cerebrum

• Lobes named for overlying skull bones: Frontal, parietal, occipital, temporal.

• Central sulcus: Separates frontal and parietal lobes.

• Other sulci: Parieto-occipital, lateral sulcus.

The Respiratory System

Nasal Mucosa

• Lines nasal cavity (except vestibule) and paranasal cavity.

• Respiratory epithelium: Pseudostratified ciliated columnar epithelium with goblet cells.

• Cilia: Whiplike, motile extensions for moving mucus.

• Goblet cells: Produce slimy mucus.

Main Bronchi

• Located in mediastinum, branches of trachea.

• Largest bronchi:

  • Left main bronchus: Longer, narrower, more horizontal.

  • Right main bronchus: Wider, shorter, more vertical.

Lungs

• Left lung: Superior and inferior lobes, oblique fissure, cardiac notch.

• Right lung: Superior, middle, and inferior lobes, oblique and horizontal fissures.

Respiratory Membrane

• Thin, delicate membrane (0.4 μm).

• Composed of alveolar and capillary walls with fused basal lamina.

• Site of O2 and CO2 exchange (Type I alveolar cells).

The Digestive System

Alimentary Canal Wall

• Four layers from esophagus to anus:

  • Mucosa: Innermost layer.

  • Submucosa: External to mucosa, contains blood, lymphatic vessels, nerves.

  • Muscularis externa: External to submucosa.

  • Serosa: Outermost layer, visceral peritoneum.

Stomach

• All typical layers of alimentary canal present.

• Stomach mucosa: Simple columnar epithelium, secretes mucus for protection.

• Mucosa dotted with gastric pits; gastric glands produce HCl and pepsinogen.

Colon

• Ascending colon: Right side of posterior abdominal wall.

• Transverse colon

• Descending colon: Left side of posterior abdominal wall.

• Sigmoid colon

Biliary Duct

• Hepatocytes secrete bile into small biliary ducts.

• Bile duct unites with common pancreatic duct to enter duodenum.

Blood and Cardiovascular System

Formed Elements

• Blood cells: Erythrocytes, leukocytes, platelets.

• Erythrocytes and platelets are not true cells (no nucleus).

• Do not divide; lifespan from hours to months.

Pericardial Cavity

• Slit space between parietal and visceral pericardium.

Heart Sounds

• Auscultatory areas of chest: Second and fifth intercostal spaces are key for heart sound assessment.

Blood Vessels

Internal Carotid Artery

• Branches: Ophthalmic, anterior cerebral, middle cerebral arteries.

• Enters cranial cavity through carotid canal of temporal bone.

• Supplies orbits and most of cerebrum.

Vasculature of Abdominal Viscera

• Celiac trunk: Supplies derivatives

• Superior mesenteric artery: Supplies midgut derivatives.

• Inferior mesenteric artery: Supplies hindgut derivatives.

Lymphatic and Immune Systems

Lymph Nodes

• Fibrous capsule: Surrounds lymph nodes.

• Trabeculae: Connective tissue strands divide node into segments.

• Afferent and efferent lymphatic vessels: Bring lymph in and out.

Splenic Pulp

• Red pulp: Surrounds white pulp, contains splenic sinusoids and cords.

• Responsible for disposing of worn-out RBCs.

Special Senses

Extrinsic Eye Muscles

• Control movement of the eyeball.

• Include superior, inferior, medial, and lateral rectus; superior and inferior oblique muscles.

The Urinary System

Kidneys

• Renal pelvis: Funnel-shaped structure for urine collection.

• Major calices: Collect urine from minor calices.

The Reproductive System

Epididymis

• Posterior to testis; duct is 6m long when uncoiled.

• Sperm take about 20 days to travel through; maturation occurs here.

Ovaries

• Tunica albuginea: Fibrous capsule of ovary.

• Ovarian cortex: Houses developing oocytes in follicles.

• Ovarian medulla: Contains blood vessels, nerves.

Table: Layers of the Alimentary Canal

Layer	Location	Main Features
Mucosa	Innermost	Epithelium, lamina propria, muscularis mucosae
Submucosa	External to mucosa	Blood vessels, lymphatics, nerves
Muscularis externa	External to submucosa	Inner circular and outer longitudinal muscle layers
Serosa	Outermost	Visceral peritoneum

Table: Blood Cell Types

Type	Function	Relative Abundance
Erythrocytes	Oxygen transport	Most abundant
Leukocytes	Immune defense	Less abundant
Platelets	Blood clotting	Least abundant

Additional info:

• Some details inferred from standard anatomy textbooks to clarify brief points and ensure completeness.

• Tables reconstructed for clarity and study purposes.