Human Pathology: Introduction, Cellular Adaptations, Injury, and Repair

Vocabulary flashcards focusing on fundamental terms in pathology, cell adaptations, causes and forms of cellular injury, and mechanisms of tissue repair and regeneration.

Pathology

The branch of medicine that investigates the essential nature of disease, especially changes in body tissues and organs that cause or are caused by disease.

Pathogenesis

The biological mechanism or process by which a disease or condition develops and progresses.

Pathophysiology

The study that focuses on the functional changes occurring in the body as a result of a disease.

Gross Morphology

The study of structural changes in diseased tissues or organs that can be recognized by the naked eye.

Microscopic Morphology

The study of structural changes in diseased tissues or organs examined using a microscope.

Histopathology

The study of tissue changes caused by disease using microscopic examination of biopsied or surgically removed samples.

Biopsy

The removal of a small sample of tissue or cells from the body for examination to diagnose or monitor a disease.

Etiology

The study of the underlying causes of a disease.

Etiologic Agent

The specific factor responsible for causing a disease state.

Biomarker

A specific molecule, gene, or characteristic that can be objectively measured and evaluated as an indicator of normal biological processes, pathogenic processes, or pharmacologic responses to a therapeutic intervention.

Acute Disease

A disease state characterized by a sudden onset and a short clinical course (often less than 1 month) that usually responds to therapy and returns to a pre-morbid state.

Chronic Disease

A disease state characterized by a slow onset and long duration (months to years) that often progresses silently and is rarely curative.

Congenital Condition

A condition or disease present at birth, acquired either through genetic inheritance or during fetal development.

Symptoms

Subjective functional implications felt and reported by the patient, such as pain or headaches, which cannot be directly measured.

Signs

Objective functional evidence discovered by a clinician that can be directly observed, measured, or tested, such as fever or elevated blood pressure.

General Pathology

The study of basic cellular and tissue reactions in response to abnormal stimuli that govern all diseases, including cellular adaptation, necrosis, inflammation, and wound healing.

Systemic Pathology

The study of specific alterations and systemic changes occurring in diseases within organ systems, such as the cardiovascular, respiratory, or gastrointestinal systems.

Homeostasis

A balanced, stable internal cellular environment that supports optimal physiological functioning.

Cellular Adaptation

Reversible structural or functional changes in cell size, number, metabolic activity, or cellular function in response to environmental changes.

Hypertrophy

An adaptive increase in the size of individual cells without an increase in cell number, resulting in increased organ or tissue volume.

Hypertrophic Cardiomyopathy

A pathologic hypertrophy of the heart marked by a thickened cardiac wall and enlargement of the left ventricle, often due to aortic stenosis.

Hyperplasia

An adaptive increase in the number of cells in an organ or tissue, usually caused by hormonal or growth factor stimulation in cells capable of division.

Atrophy

An adaptive decrease in the size or number of cells, leading to a reduction in total organ or tissue mass.

Metaplasia

A reversible cellular adaptation where one fully differentiated adult cell type is replaced by another cell type better suited to withstand environmental stress.

Reversible Cell Injury

Pathologic cellular changes that can be fully restored to normal if the injurious stimulus is removed or if the injury is mild.

Irreversible Cell Injury

Severe, permanent cellular damage that inevitably leads to cell death via necrosis or apoptosis.

Hypoxia

Oxygen deprivation that impairs aerobic cellular respiration, representing the most common cause of cell injury in clinical practice.

Healing

The overall replacement of damaged or dead tissue with healthy functional tissue, encompassing both regeneration and repair processes.

Regeneration

The restoration of lost cells and tissues with new cells of the exact same type, requiring cells capable of cell division.

Repair

The healing process wherein lost parenchymal cells are replaced by vascularized granulation tissue, which converts into fibrous scar tissue.

Labile Cells

Continuously dividing cells that proliferate throughout life and heal predominantly through regeneration, such as surface epithelial cells and hematopoietic stem cells.

Stable Cells

Quiescent cells that normally have a low rate of turnover but retain the capacity to divide when stimulated, such as hepatocytes and renal tubular cells.

Permanent Cells

Non-dividing cells that have lost the capacity for cell division and cannot regenerate, such as cardiac myocytes and central nervous system neurons.

Growth Factors

Proteins that promote cell survival, stimulate cellular proliferation, migration, and differentiation, and enhance tissue repair synthesis.

Extracellular Matrix (ECM)

A structural protein network (containing collagen and elastin) surrounding cells that provides mechanical support, regulates cell growth, and is required for tissue regeneration.

Granulation Tissue

A temporary, soft, pink tissue formed during healing, composed of proliferating fibroblasts, extracellular matrix, and newly formed capillary blood vessels.

Angiogenesis

The physiological process involving the formation of new blood vessels from pre-existing vasculature to supply oxygen, nutrients, and cells during tissue repair.