Human Anatomy and Physiology: Tissues, Systems, and Pathology

A comprehensive set of vocabulary flashcards covering basic histology, oncology, the integumentary system, the skeletal system, articulations, muscle physiology, the nervous system, and the endocrine system based on detailed lecture notes.

Epithelia

Tissues classified by the number of cell layers and the shape of cells at the apical surface, characterized by tightly packed cells and a high mitotic rate.

Simple squamous epithelium

A single layer of flat, scale-like cells found in the alveoli of lungs and endothelium of blood vessels, functioning in diffusion and filtration.

Transitional epithelium

A specialized epithelium for stretching, appearing stratified with dome-shaped surface cells when relaxed, found in the ureters and urinary bladder.

Carcinoma

A malignant tumor originating from epithelial tissue.

Sarcoma

A malignant tumor originating from connective tissue such as bone, cartilage, muscle, or fat.

Metastasis

The spread of cancer cells from a primary tumor to distant sites via blood, lymph, or body cavities.

Extracellular Matrix (ECM)

A component of connective tissue consisting of ground substance and protein fibers ($collagen$, $elastic$, and $reticular$).

Avascular

A characteristic of tissues, such as epithelia and cartilage, that lack a direct blood supply and receive nutrients through diffusion.

Osteoporosis

A disease characterized by decreased bone mass, loss of trabeculae, and thinning of cortical bone, making bones weak and brittle.

Marfan Syndrome

A connective tissue disorder caused by defective fibrillin ($ECM$ protein), leading to abnormal elastic fibers and risks such as aortic aneurysm.

Sarcomere

The functional contractile unit of striated muscle located between two $Z$ discs, containing $actin$ and $myosin$ filaments.

Myasthenia Gravis

A condition caused by autoantibodies against acetylcholine receptors at the neuromuscular junction, leading to fatigable muscle weakness.

Muscle Hypertrophy

An increase in muscle fiber size due to more myofibrils, often caused by repair and adaptation following resistance exercise.

Neuroglia (Glial Cells)

Support cells in the nervous system that provide insulation and nourishment but do not transmit electrical impulses.

Oligodendrocytes

Glial cells in the Central Nervous System ($CNS$) that form the myelin sheath around axons to increase conduction speed.

Schwann Cells

Glial cells in the Peripheral Nervous System ($PNS$) that form myelin sheaths and aid in axon regeneration.

Stratum basale

The deepest layer of the epidermis, consisting of a single layer of mitotically active stem cells where new keratinocytes are produced.

Dermis

The vascular connective tissue layer of the skin comprised of the papillary layer ($areolar$ $CT$) and the reticular layer ($dense$ $irregular$ $CT$).

Axial Skeleton

The central axis of the body consisting of the skull, hyoid bone, vertebral column, ribs, sternum, and auditory ossicles, totaling $80$ bones.

Appendicular Skeleton

The division of the skeleton comprising the limbs and the pectoral and pelvic girdles.

Periosteum

A dense connective tissue membrane covering the outer surface of bones, containing vessels, nerves, and osteoblasts for growth and repair.

Osteoblasts

Cells responsible for building bone tissue during the continuous process of bone remodeling.

Synarthrosis

A functional classification for joints that allow little to no movement, such as the sutures of the skull.

Diarthrosis

A functional classification for joints that are freely movable, such as synovial joints in the shoulder and hip.

Synovial fluid

A fluid within the joint cavity that provides lubrication, nutrient supply, and waste removal for articular cartilage.

Origin

The more fixed attachment point of a muscle, usually proximal or closer to the body's midline.

Insertion

The more movable attachment point of a muscle that is pulled toward the origin during contraction.

Flexion

A joint movement that decreases the angle between two bones.

Abduction

A movement that moves a limb or part away from the body's midline.

Meninges

The three protective membranes surrounding the $CNS$, consisting of the dura mater, arachnoid mater, and pia mater.

Cerebrospinal Fluid (CSF)

A fluid that provides buoyancy and chemical stability to the brain, circulating from the ventricles to the subarachnoid space and into dural venous sinuses.

Thalamus

The division of the diencephalon that serves as a relay station for all sensory information (except smell) and maintains consciousness.

Hypothalamus

A diencephalon region that regulates homeostasis, autonomic functions, and the pituitary gland.

Medulla oblongata

The inferior part of the brainstem containing vital centers for heart rate, respiratory rhythm, and reflexes like swallowing and vomiting.

Vagus Nerve (CN X)

A cranial nerve providing parasympathetic innervation to thoracoabdominal organs and controlling functions like swallowing and voice.

Sympathetic Division

The 'Fight or Flight' branch of the Autonomic Nervous System ($ANS$) that mobilizes energy and increases heart rate during stress.

Parasympathetic Division

The 'Rest and Digest' branch of the $ANS$ that conserves energy and promotes energy restoration and digestion.

Endocrine Gland

A ductless gland that secretes hormones directly into the bloodstream to act on distant target cells.

Negative Feedback Loop

The most common method of endocrine control where the response opposes the initial change to maintain stability.

Ricketts/Osteomalacia

A condition caused by defective mineralization of bone due to deficiency in Vitamin $D$, $Ca^{2+}$, or phosphate.