Chapter 1 Introduction: Basic Anatomy and Medical Imaging (Vocabulary Flashcards)

Vocabulary flashcards covering foundational anatomical concepts, terminology, neuroanatomy, musculoskeletal structures, and medical imaging from Chapter 1.

Bursa

A closed fibrous sac lined by synovial membrane that reduces friction where tendons, ligaments, or bones rub together.

Synovial sheath

A tubular sleeve of synovial membrane around a tendon, often with a mesotendon that carries blood vessels; reduces friction as the tendon moves.

Fascia

Connective tissue sheets that surround and separate muscles and other structures; includes superficial fascia (subcutaneous) and deep fascia (investing muscles).

Superficial fascia

Loose connective tissue layer just beneath the skin that connects skin to underlying deep fascia.

Deep fascia

Dense connective tissue that envelops muscles and other deep structures, often forming compartments via septa.

Epimysium

Outer fibrous layer surrounding a skeletal muscle, continuous with deep fascia.

Periosteum

Fibrous membrane covering bone surfaces (except articular surfaces); contains osteogenic cells and Sharpey’s fibers.

Endosteum

Membrane lining the inner surfaces of bone, lining the marrow cavity.

Bone marrow (red vs. yellow)

Red marrow is hematopoietic and present at birth; yellow marrow is fat-filled and replaces red marrow with age.

Compact bone

Dense outer bone tissue that provides strength and structure.

Cancellous (trabecular) bone

Spongy bone with a network of trabeculae found inside compact bone.

Long bone

Bones with a shaft (diaphysis) longer than wide and epiphyses at each end (e.g., femur, humerus).

Short bone

Cube-like bones (e.g., carpals, tarsals) with cancellous interior and a thin compact shell.

Flat bone

Bone with two thin layers of compact bone separated by cancellous bone (e.g., skull vault).

Irregular bone

Bones of complex shape (e.g., vertebrae) with a thin shell of compact bone and cancellous interior.

Sesamoid bone

A bone formed within a tendon; the patella is the largest example; reduces friction and alters pull direction.

Epiphysis

End of a long bone where growth occurs; contains epiphyseal plate in children.

Diaphysis

Shaft of a long bone.

Epiphyseal plate

Cartilaginous growth plate between epiphysis and diaphysis in growing bones.

Membranous ossification

Bone develops directly from connective tissue membranes (intramembranous ossification).

Endochondral ossification

Bone forms by replacing a cartilage template with bone.

Hyaline cartilage

Cartilage in joints and growth plates; firm but flexible; avascular and has limited repair.

Fibrocartilage

Cartilage with abundant collagen; found in intervertebral discs and some joint discs; repairs slowly.

Elastic cartilage

Cartilage with elastic fibers; found in ear and epiglottis; more flexible.

Joint

A site where two or more bones come together; may be movable or immovable.

Fibrous joint

Joint where bones are connected by fibrous tissue; little or no movement (e.g., skull sutures).

Cartilaginous joint

Joint joined by cartilage (synchondroses or symphyses); limited movement.

Synovial joint

Joint with a joint cavity, synovial membrane, hyaline cartilage, and a fibrous capsule; highly movable.

Plane joint

Synovial joint with nearly flat articular surfaces allowing gliding movements.

Hinge joint

Uniaxial joint permitting flexion-extension (e.g., elbow, interphalangeal joints).

Pivot joint

Joint allowing rotation around a long axis (e.g., atlas–axis; radioulnar).

Condyloid joint

Ellipsoid joint with two convex and two concave surfaces; mainly biaxial (e.g., radiocarpal).

Ellipsoid joint

Another term for an oval-shaped, biaxial joint similar to the condyloid type.

Saddle joint

Joint with reciprocal concave-convex surfaces; allows multiaxial movement (e.g., carpometacarpal of the thumb).

Ball-and-socket joint

Multiaxial joint where a spherical head fits into a socket (e.g., shoulder, hip).

Ligament

Fibrous connective tissue that binds bones at joints; can be fibrous (inelastic) or elastic.

Intracapsular ligament

Ligament located inside the joint capsule (e.g., cruciate ligaments in the knee).

Extracapsular ligament

Ligament located outside the joint capsule (e.g., many ligaments around joints).

Bursae (in general)

Small fluid-filled sacs reducing friction; commonly near joints.

Tendon

Dense connective tissue attaching muscle to bone; transmits muscle force.

Aponeurosis

Flat, broad sheet of tendon that attaches muscle to bone or to another muscle.

Raphe

Intertwingled tendinous fibers where flat muscles insert toward a tendon.

Muscle belly

Fleshy, central portion of a muscle between the attachments.

Origin

Typically the less mobile, proximal attachment of a muscle.

Insertion

Typically the more mobile, distal attachment of a muscle.

Belly

The fleshy central portion of a muscle between attachments.

Parallel (fusiform) muscle

Muscle fibers run parallel to the line of pull; greater excursion.

Pennate muscle

Muscle with fibers oblique to the tendon; includes unipennate, bipennate, multipennate; more fibers and strength, less excursion.

Agonist

Prime mover responsible for a specific movement.

Antagonist

Muscle that opposes the action of the agonist.

Fixator

Muscle that stabilizes the origin of the agonist; isometric contraction.

Synergist

Muscle that assists the agonist and helps stabilize intermediate joints.

Motor unit

One motor neuron and all the muscle fibers it innervates.

Nerve trunk

A major nerve carrying motor, sensory, and autonomic fibers to a region.

Afferent

Nerve fibers carrying impulses toward the CNS (sensory).

Efferent

Nerve fibers carrying impulses away from the CNS (motor).

Dorsal (posterior) root ganglion

Cell bodies of sensory neurons located in the posterior root ganglion.

Spinal nerve

Nerve formed by the fusion of anterior and posterior roots; divides into anterior and posterior rami.

Anterior ramus

Branch of a spinal nerve supplying anterolateral body wall and limbs; may form plexuses.

Posterior ramus

Branch of a spinal nerve supplying the back and posterior trunk.

Hilton’s law

A nerve supplying a joint also innervates the muscles moving the joint and the overlying skin.

Somatic nervous system

Voluntary nervous system that controls skeletal muscles; one-neuron pathway from CNS to muscle.

Autonomic nervous system (ANS)

Involuntary nervous system controlling smooth/cardiac muscle and glands; two-neuron pathway (preganglionic and postganglionic).

Thoracolumbar outflow

Sympathetic division outflow from T1 to L2; preganglionic fibers travel via white rami to sympathetic trunk.

Craniosacral outflow

Parasympathetic division outflow from brainstem nuclei (CN III, VII, IX, X) and S2–S4; preganglionic fibers synapse in peripheral ganglia.

Preganglionic neuron

First neuron of autonomic pathway; located in CNS; myelinated; synapses in a ganglion.

Postganglionic neuron

Second neuron of autonomic pathway; located in autonomic ganglia; unmyelinated.

Sympathetic trunk (paravertebral chain)

Chain of sympathetic ganglia running parallel to the vertebral column; site of synapses for thoracolumbar outflow.

Parasympathetic distribution

Outflow focused on head, chest/abdomen, and pelvic organs; generally less extensive than sympathetic.

Visceral afferents

Sensory fibers that travel with autonomic nerves, conveying information from internal organs.

Meninges

Three membranes surrounding the CNS: dura mater, arachnoid mater, and pia mater.

Central nervous system (CNS)

Brain and spinal cord; enclosed by meninges and filled with cerebrospinal fluid.

Peripheral nervous system (PNS)

Cranial and spinal nerves and their ganglia outside the CNS.

Dermatome

Skin area innervated by sensory fibers of a single spinal nerve; maps vary with body region.

Lymph

Clear tissue fluid collected from tissues, returned to the venous system; part of the lymphatic system.

Lymphatic vessels

Vessels that transport lymph; include capillaries, collecting vessels, and ducts (thoracic and right lymphatic).

Lacteals

Lymphatic capillaries in the villi of the small intestine that absorb chyle (fat).

Thoracic duct

Main lymphatic duct draining the left side of the body and lower right quadrant into the left venous angle.

Right lymphatic duct

Lymphatic duct draining the right side of the body above the diaphragm into the right venous angle.

Lymph nodes

Lymphatic organs that filter lymph and host immune responses.

Mucous membrane

Lining of lumenal surfaces; consists of epithelium and lamina propria; may have muscularis mucosae.

Serous membrane

Membranes lining thoracic and abdoinopelvic cavities and covering viscera; parietal and visceral layers with serous fluid.

Pleura

Serous membranes surrounding the lungs (visceral and parietal layers) with pleural cavity and fluid.

Embryology: germ layers

Ectoderm forms skin and CNS; mesoderm forms muscles, bones, and connective tissue; endoderm forms mucosal linings and glands.

Neural plate and neural tube

Thickened ectoderm forms neural plate which folds to form the neural tube, giving rise to CNS.

Anatomical position

Standard reference posture: standing, facing forward, arms at sides, palms forward.

Planes (anatomy)

Median (midsagittal), sagittal, coronal (frontal), and horizontal (transverse) planes.

Eponyms

Terms named after people; TA guidelines advise avoiding eponyms in formal terminology.

Radiography (X-ray)

Imaging using X-rays to form images based on tissue density; bones appear radiopaque (white).

Computed Tomography (CT)

Imaging method using rotating X-ray beams and computer reconstruction to form axial cross-sections.

Magnetic Resonance Imaging (MRI)

Imaging using strong magnetic fields and radiofrequency pulses; excellent soft-tissue contrast without ionizing radiation.

Ultrasound

Imaging using high-frequency sound waves to create real-time images based on reflections.

Nuclear medicine imaging

Imaging using radioactive tracers to assess function and physiology (e.g., PET, SPECT).