Pathophysiology and Epidemiology Key Terms Flashcards

Vocabulary practice flashcards covering key definitions in pathophysiology, epidemiology, genetics, stress response, and immunology based on lecture notes.

Etiology

The cause of a disease.

Pathogenesis

Biological understanding of how the cause of disease leads to structural and functional physiological changes that result in disease.

Pathophysiology

The study of functional changes that occur in the body as a result of injury, disorder, or disease.

Disease

A significant disturbance in homeostasis that modifies the performance of vital functions.

Risk Factor

An agent or condition that increases the probability of developing a disease.

Etiologic Factor

A specific type of risk factor that serves as the direct cause of a disease.

Modifiable Risk Factor

A risk factor that can be intervened upon or altered, such as a high cholesterol diet versus a genetic predisposition.

Signs

Objective evidence of disease observed during a physical examination.

Symptoms

Subjective indications of disease reported directly by the patient.

Prognosis

The predicted outcome of a disease.

Remission

A period during which the signs and symptoms of a disease subside.

Recurrence

The return of a sign or symptom following a period of remission.

Relapse

The return of a disease weeks or months after an apparent cure.

Exacerbation

A sudden or progressive increase in the severity of signs and symptoms.

Complication

A related disease or altered state that develops in an individual already suffering from a primary disease.

Disorder

A functional abnormality not necessarily linked to a specific cause or physical abnormality.

Syndrome

An abnormal function or structure characterized by a group of signs and symptoms that usually occur together.

Natural History of Disease

The progression of a disease process in an individual over time, consisting of the normal phase (no disease), preclinical phase (biological onset without symptoms), and clinical phase (symptoms appear, leading to diagnosis and treatment).

Active Transport

Movement of substances across a cell membrane requiring ATP because it moves against the concentration gradient.

Passive Transport

Movement of substances across a cell membrane that does not require ATP, such as diffusion and facilitated diffusion.

Diffusion

The passive movement of particles from an area of high concentration to an area of low concentration, requiring no energy or transport proteins.

Facilitated Diffusion

A form of passive transport across a biological membrane that requires specific transport proteins.

Phagocytosis

The process by which a cell ingests large particles and releases oxygen-free radicals.

Proliferation

An increase in the total number of cells through cell division.

Differentiation

Process involving changes in physical and functional properties of cells that directs their development into specialized cell types.

Necrosis

Unregulated cell death resulting from cell injury and associated with inflammation.

Apoptosis

Programmed, genetically directed cell death designed to replace old cells with new ones.

Hypertrophy

An increase in cell size resulting from hormone signaling, mechanical stress, or increased demand.

Hyperplasia

An increase in the total number of cells within a tissue or organ.

Metaplasia

The transformation of one adult cell type into another in response to persistent stress, which can return to normal when the stressor is removed.

Atrophy

A decrease in cell size caused by disuse, decreased oxygen, nutritional deprivation, or removal of hormonal signals.

Dysplasia

Abnormal changes in cell size, shape, uniformity, arrangement, and structure in response to a stressor, which can progress to cancer.

Morbidity

The burden of disease within a population, or the state of being diseased.

Incidence

The number of new disease cases occurring in a population during a specified period.

Case Fatality Rate

The probability of dying from a specific disease after contracting it.

Genomics

The study of all genes in a genome and their complex interactions.

Genetics

The study of single genes and their specific effects on health.

Intron

Non-coding DNA segments within a gene.

Exon

DNA segments that directly code for proteins during protein synthesis.

Meiosis

Cell division that reduces the parent cell chromosomes by half and produces 4 gamete cells.

Mitosis

A form of cell division where a single cell divides into 2 identical daughter cells.

Autosomal Dominant Inheritance

An inheritance pattern where inheriting a single affected allele from one parent produces the trait, affecting males and females equally.

Autosomal Recessive Inheritance

An inheritance pattern requiring two carrier parents to pass on the trait; two heterozygous parents have a $25\%$ chance of producing an affected child.

Malignant Tumor

A life-threatening cancerous tumor that invades surrounding tissue, lacks a uniform appearance, and has the potential to metastasize.

Benign Tumor

A non-life-threatening tumor that grows slowly, resembles original cells, and will not metastasize.

Carcinogenesis

The process by which normal cells transform into cancerous cells due to DNA mutations, proceeding through initiation, promotion, and progression.

Initiation (Carcinogenesis)

The first stage of carcinogenesis involving permanent genetic change to a cell caused by exposure to a carcinogen.

Promotion (Carcinogenesis)

The expansion and hyperproliferation of an initiated cell, driven by exposure to a carcinogen.

Progression (Carcinogenesis)

The final stage of carcinogenesis where cells turn malignant, displaying rapid growth, evolutionary advantage, and invasive properties.

Oncogenes

Genes that signal cells when to divide; mutations in oncogenes lead to improper and continuous cell division.

Tumor Suppressor Genes

Genes that instruct cells when not to divide, keeping cell division in check.

Allostatic Load

The cumulative physiological consequence of repeated or sustained activation of mediators of allostasis, leading to decreased system efficiency.

HPA Axis Response

Neuroendocrine stress pathway initiated when a stressor prompts the hypothalamus to release CRH, driving the pituitary gland to secrete ACTH, which signals the adrenal glands to release cortisol.

Calor

Cardinal sign of acute inflammation corresponding to localized heat.

Rubor

Cardinal sign of acute inflammation corresponding to redness.

Dolor

Cardinal sign of acute inflammation corresponding to pain.

Tumor (Inflammation)

Cardinal sign of acute inflammation corresponding to swelling.

Functio Laesa

Cardinal sign of acute inflammation corresponding to loss of function.

Antigens

Foreign substances recognized by the body as "non-self".

Innate Immunity

Nonspecific immune defense mechanism that responds first to prevent entry and spread of pathogens through physical, chemical, and cellular defenses.

Adaptive Immunity

Slower, highly specific immune response targeted against specific pathogen antigens that builds immunologic memory.

Humoral Immunity

Branch of adaptive immunity that provides defense against extracellular antigens (such as bacterial toxins and cells) through the action of antibodies produced by B cells.

Antibodies

Y-shaped proteins produced by B cells that bind to specific antigens and tag invaders for destruction via phagocytosis.

Cell-Mediated Immunity

Branch of adaptive immunity governed by T cells that targets viruses, abnormal cells, and intracellular pathogens.

Active Immunity

Long-term protection achieved when exposure to a foreign organism stimulates immune cells to produce specific antibodies and memory cells.

Passive Immunity

Short-term protection achieved through the transfer of pre-formed antibodies to an individual without forming memory cells (e.g., maternal transfer in utero).

Attenuated Vaccine

Vaccine containing a weakened, live form of a pathogen that elicits a strong immune response with a small possibility of infection.

Inactivated Vaccine

Vaccine containing killed or inactivated pathogens (via heat or chemicals) that is stable and safer, but produces a weaker immune response.

Basic Reproduction Number ($R_0$)

The average number of secondary infections produced by one infected individual in a completely unprotected population.

Antigenic Drift

Small genetic changes in viruses that occur continually over time.

Antigenic Shift

An abrupt, major change in a virus resulting in completely new surface proteins that can overwhelm the immune system.

Anaphylaxis

A severe, life-threatening systemic allergic reaction characterized by constriction of blood vessels.