Patho - Pre-Class Lecture

Vocabulary flashcards covering cell functions, tissue types, ECM components, organelles, chromosomal abnormalities, DNA replication enzymes, and epigenetics from ELMSN Pathophysiology.

Epithelial Tissue

A basic tissue type that covers exterior surfaces and body cavities.

Connective Tissue

A basic tissue type that connects and supports cells and organs, providing protection, insulation, and energy storage.

Muscle Tissue

A basic tissue type responsible for contraction and producing movement.

Nervous Tissue

A basic tissue type responsible for the generation and propagation of nerve impulses.

Fibroblasts

Specialized cells that synthesize the extracellular matrix (ECM) in fibrous connective tissue.

Chondrocytes

Specialized cells that synthesize the extracellular matrix (ECM) in cartilage.

Osteoblasts

Specialized cells that synthesize the extracellular matrix (ECM) in bone.

Conductivity

A chief cellular function of nerve cells manifested by a wave of excitation (an electrical potential) passing along the surface of the cell in response to a stimulus.

Lysosomes

Membrane-bound intracellular organelles containing digestive enzymes that break down large molecules and cellular waste; dysfunction leads to lysosomal storage diseases such as Tay-Sachs and Gaucher disease.

Collagen

An extracellular matrix protein that provides tissues with tensile strength; excess production by lung fibroblasts in pulmonary fibrosis causes stiff lungs and impaired gas exchange.

Glycosaminoglycans (GAGs)

Polar, often sulfated (negatively charged) ECM molecules that attract water and enable tissues to resist compressive forces.

Elastin

An extracellular matrix protein that provides tissues with the ability to recoil after stretching.

Cytosol

The fluid component of eukaryotic cells that serves as the site for many metabolic reactions and protein synthesis.

Nucleus

Organelle that stores DNA, controls gene expression, and serves as the site of DNA replication and RNA synthesis.

Endoplasmic Reticulum (ER)

Organelle divided into rough ER (protein synthesis) and smooth ER (lipid synthesis) that transports newly synthesized molecules.

Golgi Apparatus

Organelle that modifies, sorts, packages, and ships proteins and lipids for secretion or cellular delivery.

Mitochondria

Organelles responsible for generating ATP through aerobic respiration.

Peroxisomes

Organelles that break down fatty acids and detoxify harmful substances to protect cells from oxidative damage.

Microtubules

Cytoskeletal components essential for cell division, intracellular transport of vesicles, and the movement of cilia and flagella.

Actin Filaments

Cytoskeletal components involved in muscle contraction (thin filaments), cell movement across surfaces, and maintaining cell shape.

Karyotype

An organized display of an individual's 46 chromosomes (23 pairs) arranged by size and chromosome number.

Aneuploidy

A chromosomal abnormality in which one or more sets of chromosomes in a cell have a different number of chromosomes compared to normal sets, often caused by nondisjunction or chromosome loss.

Patau Syndrome

An autosomal aneuploidy (Trisomy 13) occurring in approximately 1 in 10,000–20,000 live births, characterized by severe intellectual disability, cleft lip/palate, congenital heart defects, brain abnormalities, polydactyly, and high infant mortality.

Edwards Syndrome

An autosomal aneuploidy (Trisomy 18) occurring in approximately 1 in 5,000–6,000 live births, characterized by severe developmental delay, clenched fists with overlapping fingers, congenital heart defects, rocker-bottom feet, and high infant mortality.

Down Syndrome

An autosomal aneuploidy (Trisomy 21) occurring in approximately 1 in 700–800 live births, characterized by mild to moderate intellectual disability, characteristic facial features, hypotonia, congenital heart defects, and increased risk of leukemia and early-onset Alzheimer's disease.

Klinefelter Syndrome

A sex chromosome aneuploidy (XXY) occurring in approximately 1 in 600–1,000 males, characterized by tall stature, small testes, infertility, gynecomastia, and decreased testosterone.

Jacob Syndrome

A sex chromosome aneuploidy (XYY) occurring in approximately 1 in 1,000 males, characterized by tall stature, normal sexual development, and possible learning or behavioral difficulties.

Triple X Syndrome

A sex chromosome aneuploidy (XXX) occurring in approximately 1 in 1,000 females, often asymptomatic and characterized by tall stature, possible learning difficulties, and normal fertility in most individuals.

Turner Syndrome

A sex chromosome aneuploidy with a 45,X karyotype occurring in approximately 1 in 2,500 female live births, characterized by short stature, webbed neck, ovarian insufficiency, infertility, and congenital heart defects such as coarctation of the aorta.

DNA Helicase

Enzyme responsible for unwinding double-stranded DNA during replication by breaking hydrogen bonds between strands.

Topoisomerase

Enzyme that relieves supercoiling ahead of the replication fork during DNA replication.

Single-Strand Binding Proteins

Proteins that stabilize parental DNA strands and keep them apart during DNA replication.

Primase

Enzyme that synthesizes a short RNA primer required to start DNA replication.

DNA Polymerase III

Enzyme that synthesizes new DNA strands in the $5' \rightarrow 3'$ direction during replication.

DNA Polymerase I

Enzyme that removes RNA primers and replaces them with DNA during replication.

DNA Ligase

Enzyme that seals nicks by joining Okazaki fragments on the lagging strand during DNA replication.

Epigenetics

The study of inherited or modifiable DNA alterations (such as histone modifications and cytosine methylation) that change gene expression levels without altering the underlying DNA sequence.