Cell as a Unit of Life & Cell Injury and Adaptations – Vocabulary Flashcards

Vocabulary flashcards covering key concepts from the notes on cell structure, injury, apoptosis, necrosis, calcifications, metaplasia, aging, and related cellular processes.

Which of the following best describes an Integral protein? A. A transmembrane protein that spans the lipid bilayer and is embedded in the plasma membrane. B. A protein loosely associated with the cell membrane surface. C. A protein found exclusively in the cytoplasm. D. A protein forming the cell wall in plants.

A.

What is Copy number variation (CNV)? A. A form of genetic variation involving changes in the number of copies of large DNA segments. B. A single nucleotide polymorphism that alters protein function. C. A type of mutation where a single gene is inverted. D. A structural change leading to a permanent gene deletion.

A.

Hepatocyte growth factor (scatter factor) primarily stimulates which of the following in keratinocytes? A. Migration, proliferation, and differentiation. B. Apoptosis and cell cycle arrest. C. Increased synthesis of melanin. D. Formation of intercellular tight junctions.

A.

Cytokeratin is an intermediate filament used as a diagnostic marker for carcinomas arising from which cell type? A. Epithelial cells. B. Muscle cells. C. Connective tissue cells. D. Neural cells.

A.

Which statement accurately describes Laminin? A. A major basement membrane glycoprotein that helps anchor epithelial cells to the underlying matrix. B. A protein involved in forming tight junctions between cells. C. A component of the nuclear envelope. D. A fibrous protein important in muscle contraction.

A.

What is the primary function of MicroRNA (miRNA)? A. Small noncoding RNAs that regulate translation of target mRNAs; they do not encode proteins. B. Enzymes that degrade proteins. C. Proteins that facilitate DNA replication. D. Large RNAs that encode proteins for cellular structure.

A.

The Proteasome is a protein complex responsible for which cellular process? A. Degrades ubiquitin-tagged cytosolic and nuclear proteins. B. Synthesizes new proteins based on mRNA templates. C. Produces ATP through oxidative phosphorylation. D. Forms vesicles for exocytosis.

A.

When exposed on the outer leaflet of the plasma membrane, Phosphatidylserine signals which process? A. Phagocytosis in apoptosis. B. Cell proliferation. C. Cell adhesion. D. Protein synthesis.

A.

What type of junction is a Hemidesmosome? A. Anchoring junction that connects epithelial cells to the extracellular matrix. B. A tight junction that seals cells together. C. A gap junction for intercellular communication. D. A desmosome that connects cells to other cells.

A.

Which characteristic defines a Stem cell? A. Cell capable of self-renewal and differentiation into multiple cell types to form tissues. B. A fully differentiated cell with a specific function. C. A cell that only undergoes apoptosis. D. A terminally differentiated cell incapable of division.

A.

What is Pathogenesis? A. The sequence of events and mechanisms leading to disease development. B. The study of disease incidence in populations. C. The diagnosis of disease based on symptoms. D. The treatment of diseases using pharmacological agents.

A.

Which statement accurately describes Reversible injury? A. Cell injury that can be reversed if the stress is removed; characterized by cellular swelling and blebbing. B. Irreversible cell injury leading to cell death. C. Cell injury always resolved by apoptosis. D. A type of injury specific to bacterial infections.

A.

Which of the following is an example of a Physical agent causing cell injury? A. Physical factors (e.g., electrocution, trauma, heat/cold) that cause cellular injury. B. Bacterial toxins. C. Genetic mutations. D. Nutritional deficiencies.

A.

What is the correct sequence of Sequential changes in cell injury? A. Biochemical changes "➔" ultrastructural changes "➔" light microscopic changes "➔" gross changes. B. Gross changes "➔" light microscopic changes "➔" biochemical changes "➔" ultrastructural changes. C. Ultrastructural changes "➔" gross changes "➔" biochemical changes "➔" light microscopic changes. D. Light microscopic changes "➔" biochemical changes "➔" gross changes "➔" ultrastructural changes.

A.

Which characteristic defines Necrosis? A. Irreversible cell injury with membrane disintegration and enzymatic digestion, often accompanied by inflammation. B. Programmed cell death with intact membranes. C. A reversible cell adaptation. D. Cell repair without tissue damage.

A.

What is Karyolysis? A. Nuclear fading/dissolution due to DNA degradation during necrosis. B. Nuclear shrinkage and increased basophilia. C. Fragmentation of the nucleus. D. Formation of new nuclear envelopes.

A.

Coagulative necrosis is best described as a necrosis pattern with which feature? A. Preserved tissue architecture for a time, common in ischemic injury. B. Complete dissolution of tissue architecture, leaving a pus-filled cavity. C. Accumulation of immune complexes in vessel walls. D. Formation of fatty acid soaps.

A.

What is characteristic of Fibrinoid necrosis? A. Necrosis with immune complex deposition in vessel walls giving bright pink, fibrin-like appearance. B. Tissue architecture is preserved due to protein denaturation. C. Occurs in the brain due to bacterial infection. D. Affects adipose tissue due to lipase activation.

A.

Which of the following is an example of Physiologic apoptosis? A. Programmed cell death that occurs during development or normal physiology (e.g., hormone withdrawal). B. Cell death due to acute injury and inflammation. C. Uncontrolled cell proliferation in tumors. D. Accidental cell death from trauma.

A.

BAD is a pro-apoptotic BH3-only protein in the Bcl-2 family that promotes which process? A. Apoptosis. B. Cell proliferation. C. DNA repair. D. Protein synthesis.

A.

What is the role of BAK, a pro-apoptotic Bcl-2 family protein? A. Promotes mitochondrial outer membrane permeabilization. B. Inhibits mitochondrial outer membrane permeabilization. C. Activates anti-apoptotic pathways. D. Synthesizes new mitochondrial proteins.

A.

BCL2 is an anti-apoptotic Bcl-2 family protein that primarily performs which action? A. Inhibits apoptosis. B. Initiates apoptosis. C. Promotes mitochondrial outer membrane permeabilization. D. Activates caspases directly.

A.

The BH3 domain in pro-apoptotic Bcl-2 family members mediates which signaling process? A. Protein interaction domain in pro-apoptotic Bcl-2 family members mediating apoptosis signaling. B. DNA binding. C. RNA synthesis. D. ATP hydrolysis.

A.

When released into the cytosol, Cytochrome c plays what role in apoptosis? A. Mitochondrial protein released into the cytosol to activate the intrinsic apoptotic cascade. B. Acts as a direct inhibitor of caspases. C. Is involved in DNA repair. D. Functions as a growth factor.

A.

The Apoptosome is a protein complex formed by cytochrome c, APAF-1, and procaspase-9 that performs which action? A. Activates caspase-9. B. Degrades cellular proteins. C. Initiates DNA replication. D. Repairs mitochondrial damage.

A.

The Death domain is an extrinsic apoptosis signaling domain that mediates what? A. Death receptor signaling. B. Intracellular transport. C. Cell-cell adhesion. D. Nuclear pore formation.

A.

Autophagy is a catabolic process often activated during starvation or stress. What is its primary function? A. Degrades and recycles cellular components. B. Synthesizes new cellular organelles. C. Promotes cell proliferation. D. Repairs extracellular matrix proteins.

A.

Catalase is a peroxisomal enzyme that performs which function? A. Decomposes hydrogen peroxide into water and oxygen. B. Catalyzes the formation of hydrogen peroxide. C. Synthesizes fatty acids. D. Degrades cellular waste products in lysosomes.

A.

Which statement describes the function of Glutathione peroxidase? A. Enzyme that reduces hydrogen peroxide to water using glutathione. B. Produces glutathione from amino acids. C. Oxidizes glutathione to generate ATP. D. Synthesizes superoxide radicals.

A.

Free radicals can cause which of the following effects? A. Reactive species that can cause lipid peroxidation, protein oxidation, and DNA damage. B. Promote cell growth and differentiation. C. Enhance DNA repair mechanisms. D. Protect cells from oxidative stress.

A.

What are Inclusion bodies? A. Cytoplasmic aggregates of abnormal proteins, such as misfolded intermediates. B. Normal cellular organelles involved in metabolism. C. Structures found only in the nucleus. D. Temporary storage sites for nutrients.

A.

Lipofuscin is known as a "wear-and-tear" pigment because it accumulates over time. What is its nature? A. Age-related lysosomal residue. B. A form of stored glycogen. C. A metabolic byproduct of heme degradation. D. A pigment involved in skin coloration.

A.

Brown atrophy is a condition associated with the accumulation of which pigment in aging tissues? A. Lipofuscin. B. Hemosiderin. C. Melanin. D. Bilirubin.

A.

Which statement describes Hemosiderin? A. Iron-containing pigment derived from ferritin; accumulates after bleeding or iron overload. B. A calcium-containing pigment found in atherosclerotic plaques. C. A non-iron containing pigment responsible for skin color. D. A type of protein aggregate in neurodegenerative diseases.

A.

What is the characteristic appearance of Hyaline change on routine H&E staining? A. Pink (eosinophilic) homogeneous appearance. B. Bluish (basophilic) granular appearance. C. Yellowish amorphous deposits. D. Black crystalline structures.

A.

Endocrine atrophy is caused by which factor? A. Loss of hormonal stimulation (e.g., menopause). B. Increased functional demand. C. Chronic inflammation. D. Genetic predisposition only.

A.

Russell bodies are described as cytoplasmic eosinophilic inclusions composed of what, found within plasma cells? A. Immunoglobulins. B. Misfolded proteins from viral infections. C. Glycogen granules. D. Lipid droplets.

A.

Metastatic calcification involves the calcification of normal tissues due to what underlying condition? A. Hypercalcemia or imbalanced calcium metabolism. B. Local tissue necrosis with normal calcium levels. C. Inflammation and infection. D. Accumulation of foreign bodies.

A.

Which of the following best defines Metaplasia? A. Replacement of one differentiated cell type by another; often an adaptive response to stress. B. An increase in cell size without an increase in cell number. C. A decrease in cell number. D. A disordered growth and maturation of cells.

A.

Werner syndrome (WRN) is a premature aging syndrome caused by a defect in which type of protein? A. A RecQ family helicase (WRN). B. A DNA polymerase. C. A histone deacetylase. D. A ribosomal protein.

A.

Psammoma bodies are described as what type of structures, commonly seen in certain neoplasms? A. Lamellated calcified bodies. B. Lipid-filled vacuoles. C. Protein aggregates without calcification. D. Glycogen storage granules.

A.

What is the relationship between Metaplasia and malignancy risk? A. Metaplasia can predispose to malignant transformation depending on context. B. Metaplasia always leads to malignancy. C. Metaplasia has no association with malignancy risk. D. Metaplasia directly causes apoptosis in mutated cells.

A.

What is Hypertrophy? A. Increase in cell size (not cell number), often due to functional demand (e.g., uterus in pregnancy). B. Increase in cell number. C. Decrease in cell size. D. Replacement of one cell type by another.

A.

Lysosomal storage diseases are characterized by which cellular pathology? A. Accumulation of undegraded substrates due to lysosomal enzyme defects. B. Excessive synthesis of lysosomal enzymes. C. Impaired protein synthesis in the endoplasmic reticulum. D. Defective mitochondrial energy production.

A.

Dystrophic calcification occurs specifically in which type of tissue? A. Necrotic or dead tissue despite normal calcium metabolism. B. Normal, healthy tissue due to high calcium levels. C. Inflamed tissue undergoing repair. D. Actively dividing tissue.

A.

What is the main characteristic of Type IV collagen? A. Main collagen type found in basement membranes. B. Primary component of tendons and ligaments. C. Forms elastic fibers in blood vessels. D. Found predominantly in cartilage.

A.

How do Neurons respond to hypoxic injury? A. Neurons are among the most sensitive cells to hypoxic injury. B. Neurons are highly resistant to hypoxic injury. C. Neurons undergo hyperplasia in response to hypoxia. D. Neurons repair themselves completely after severe hypoxia.

A.

E-cadherin is a calcium-dependent cell-cell adhesion molecule that is part of which type of junctions? A. Anchoring junctions. B. Gap junctions. C. Tight junctions. D. Plasmodesmata.

A.

Which is the most accurate description of the Glycocalyx? A. Oligosaccharide-rich mesh on the cell surface extending outward; involved in cell recognition. B. A layer of lipids forming the cell membrane. C. A protein layer found beneath the cell membrane. D. The internal cytoskeleton of the cell.

A.

ER stress is triggered by which cellular event? A. Accumulation of misfolded proteins in the endoplasmic reticulum triggering unfolded protein response. B. Deficiency of ATP production in mitochondria. C. Excessive lipid storage in the cytoplasm. D. Disruption of nuclear membrane integrity.

A.

The sperm tail (flagellum) is built with a core primarily composed of what? A. Microtubules (axoneme). B. Actin filaments. C. Intermediate filaments. D. Collagen fibers.

A.

Saponification refers to the reaction of fatty acids with calcium to form what in necrotic tissue? A. Calcium soaps. B. Cholesterol crystals. C. Glycogen stores. D. Collagen bundles.

A.

Which endogenous pigment accumulates in macrophages after multiple transfusions? A. Hemosiderin. B. Lipofuscin. C. Melanin. D. Bilirubin.

A.

Gums are generally not predisposed to metastatic calcification. Which of the following is considered a common site for metastatic calcification? A. Common sites include stomach, lungs, kidneys. B. Skeletal muscle. C. Adipose tissue. D. Lymph nodes.

A.

The Glycocalyx is a carbohydrate-rich layer on the cell surface formed by what? A. Oligosaccharide chains. B. Phospholipid bilayers. C. Integral membrane proteins. D. Cholesterol molecules.

A.

Caspases are cysteine proteases central to the execution phase of apoptosis and also play a role in what other process? A. Also play a role in development. B. Cell proliferation. C. DNA repair. D. Energy production.

A.

A defect in which protein leads to connective tissue weakness as seen in Marfan syndrome? A. Elastic fiber protein; defect leads to connective tissue weakness as seen in Marfan syndrome. B. Collagen. C. Fibronectin. D. Laminin.

A.

What is the primary function of a Ribosome? A. Cytoplasmic organelle that assembles polypeptides on tRNA according to mRNA (protein synthesis). B. Produces ATP. C. Degrades waste proteins. D. Stores genetic information.

A.

Besides aerobic respiration and ATP production, Mitochondria are also central in what other major cellular process? A. Apoptosis signaling. B. Cellular detoxification. C. Lipid synthesis. D. Glycogen storage.

A.

Which statement accurately describes Embryonic stem cells? A. Totipotent/pluripotent cells capable of differentiating into multiple lineages. B. Are highly differentiated cells. C. Only differentiate into a single cell type. D. Are incapable of self-renewal.

A.

E-cadherin is a part of adherens junctions that mediate what in epithelia? A. Cell-cell adhesion. B. Cell-matrix adhesion. C.

A.