D236 Pathophysiology - Set 1 - Part 1

Correct Answer: Excessive osteoclastic activity

Osteoporosis develops when osteoclasts break down bone faster than osteoblasts can rebuild it, leading to weakened bones prone to fractures.
Option a is incorrect because enhanced osteoblast activity would actually strengthen bones by increasing bone formation rather than causing fragility.
Option b is incorrect because decreased osteoclast function would result in denser bones, not the fragile bones seen in osteoporosis.
Option d is incorrect because increased calcium absorption would help strengthen bones, not weaken them as seen in this patient.

Correct Answer: Mast cells

Mast cells are the primary cellular activators of inflammation, releasing histamine and other mediators that increase vascular permeability for immune response.
Option a is incorrect because dendritic cells primarily function as antigen presenters to activate adaptive immunity, not histamine release.
Option c is incorrect because neutrophils are phagocytic cells that engulf pathogens but are not the primary histamine releasers.
Option d is incorrect because lymphocytes are involved in adaptive immunity and antibody production, not immediate histamine release.

Correct Answer: Respiratory rate increase

The respiratory system responds within minutes by increasing breathing rate to expel carbon dioxide, raising pH quickly during metabolic acidosis.
Option a is incorrect because the protein buffer system acts immediately but has limited capacity compared to respiratory compensation mechanisms.
Option b is incorrect because renal compensation takes hours to days to fully activate, making it slower than respiratory responses.
Option d is incorrect because phosphate buffers work primarily in intracellular fluid and are not the first compensatory mechanism activated.

Correct Answer: Autosomal recessive inheritance

Autosomal recessive conditions require two mutated gene copies, one from each parent, with carriers having one normal allele masking symptoms.
Option a is incorrect because autosomal dominant conditions manifest with just one mutated gene copy from either parent present.
Option c is incorrect because X-linked dominant conditions affect females more severely and don't require both parents as carriers.
Option d is incorrect because mitochondrial inheritance comes exclusively from the mother, not requiring genes from both parents equally.

Correct Answer: Granulation tissue formation

Granulation tissue with new blood vessels forms after initial hematoma, creating a scaffold for subsequent bone callus formation.
Option a is incorrect because hematoma formation is the immediate blood clot response, not the vascular tissue development phase.
Option c is incorrect because callus formation occurs after granulation tissue establishes the vascular foundation for bone growth.
Option d is incorrect because remodeling is the final phase where mature bone replaces immature bone tissue completely.

Correct Answer: RNA polymerase enzyme

RNA polymerase reads DNA template strands and synthesizes complementary RNA molecules during transcription in the nucleus before translation.
Option a is incorrect because DNA polymerase replicates DNA during cell division, not for creating RNA from DNA templates.
Option c is incorrect because helicase unwinds DNA double helix but doesn't synthesize RNA molecules from DNA templates.
Option d is incorrect because ligase joins DNA fragments together during replication and repair, not RNA synthesis processes.

Correct Answer: Mechanical stress degeneration

Osteoarthritis results from mechanical wear causing cartilage breakdown, subchondral bone changes, and compensatory osteophyte formation in joints.
Option a is incorrect because acute inflammation causes sudden joint swelling and pain, not the gradual degenerative changes described.
Option c is incorrect because autoimmune destruction affects multiple joints symmetrically with systemic inflammation, unlike mechanical wear patterns.
Option d is incorrect because infectious damage causes rapid joint destruction with fever and systemic symptoms, not gradual changes.

Correct Answer: Two hit hypothesis

Knudson's two hit hypothesis states that cancer requires mutations in both alleles, with one potentially inherited and one acquired.
Option a is incorrect because single mutations alone rarely cause cancer, as cells have backup mechanisms from paired alleles.
Option c is incorrect because while multiple mutations occur, the fundamental requirement is damage to both alleles of tumor suppressors.
Option d is incorrect because cancer development follows predictable genetic patterns rather than occurring spontaneously without genetic changes.

Correct Answer: Endometriosis condition

Endometriosis occurs when endometrial tissue grows outside the uterus, causing pain, inflammation, and potential infertility complications.
Option a is incorrect because pelvic inflammatory disease involves bacterial infection of reproductive organs, not ectopic endometrial tissue growth.
Option c is incorrect because adenomyosis involves endometrial tissue within uterine muscle walls, not external reproductive organ involvement.
Option d is incorrect because polycystic ovarian syndrome involves hormonal imbalances and cyst formation, not ectopic endometrial tissue.

Correct Answer: Lipid metabolism activation

Lipolysis with ketone formation occurs when cells cannot use glucose properly, producing acidic ketones that dangerously lower blood pH.
Option a is incorrect because glucose metabolism is actually impaired in diabetic ketoacidosis, forcing alternative energy pathway activation.
Option b is incorrect because while protein breakdown occurs, it doesn't produce the ketone bodies responsible for acidosis.
Option d is incorrect because glycogen storage is depleted, not enhanced, during the metabolic crisis of diabetic ketoacidosis.

Correct Answer: X-linked recessive pattern

X-linked recessive disorders like hemophilia affect males who inherit one defective X chromosome, lacking a second X for compensation.
Option a is incorrect because autosomal dominant conditions affect non-sex chromosomes and appear equally in both males and females.
Option b is incorrect because autosomal recessive conditions require two defective copies and affect males and females equally often.
Option d is incorrect because Y-linked inheritance only affects male-specific traits and is extremely rare in disease conditions.

Correct Answer: Diarthrosis joint type

Diarthrosis or synovial joints like knees and shoulders provide maximum mobility with synovial fluid lubricating cartilage surfaces effectively.
Option a is incorrect because synarthrosis joints are immovable connections like skull sutures without any significant movement capability.
Option b is incorrect because amphiarthrosis joints allow only slight movement, like vertebral joints with limited flexibility ranges.
Option d is incorrect because fibrous joints are generally immovable or slightly movable without synovial fluid for lubrication.

Correct Answer: Diapedesis movement

Diapedesis or extravasation allows white blood cells to squeeze through endothelial junctions following chemical gradients to infection sites.
Option a is incorrect because phagocytosis is the engulfing and digesting of pathogens, not the migration through vessel walls.
Option c is incorrect because opsonization marks pathogens for destruction but doesn't describe white blood cell movement through vessels.
Option d is incorrect because complement activation enhances immune responses but doesn't specifically describe cell migration through vessels.

Correct Answer: Gonorrhea and chlamydia

Gonorrhea and chlamydia commonly cause pelvic inflammatory disease, leading to tubal scarring and subsequent infertility if untreated.
Option a is incorrect because herpes causes painful vesicles but rarely leads to fallopian tube scarring and infertility.
Option c is incorrect because human papillomavirus causes cervical changes and warts but not typically tubal scarring patterns.
Option d is incorrect because candida causes vaginal yeast infections with discharge but doesn't ascend to damage fallopian tubes.

Correct Answer: Osteoblast cells

Osteoblasts synthesize and deposit new bone matrix during callus formation, gradually replacing cartilage with mineralized bone tissue.
Option a is incorrect because osteoclasts break down and resorb bone tissue rather than creating new bone matrix material.
Option c is incorrect because chondrocytes produce cartilage in the soft callus but don't directly create bone matrix.
Option d is incorrect because fibroblasts produce connective tissue and collagen but not the specialized bone matrix material.

Correct Answer: Hyperosmolar hyperglycemic syndrome

Hyperosmolar hyperglycemic nonketotic syndrome presents with severely elevated glucose without ketone production, causing dangerous osmotic shifts.
Option a is incorrect because diabetic ketoacidosis always involves ketone production along with hyperglycemia and acidosis development.
Option b is incorrect because hypoglycemic crisis involves dangerously low blood glucose, not the extreme elevation described here.
Option d is incorrect because insulin shock results from excessive insulin causing hypoglycemia, not hyperglycemia without ketones.

Correct Answer: Mitochondria organelle

Mitochondria contain maternal DNA that, when mutated, can cause various disorders including neurodegenerative and cardiac conditions.
Option a is incorrect because nuclear DNA comes from both parents equally, not exclusively from the mother's genetic contribution.
Option c is incorrect because ribosomes synthesize proteins using messenger RNA but don't contain their own inheritable DNA.
Option d is incorrect because endoplasmic reticulum processes proteins and lipids but lacks its own genetic material entirely.

Correct Answer: CRISPR editing technology

CRISPR technology enables precise DNA editing to correct genetic defects, showing promise in treating various inherited diseases successfully.
Option a is incorrect because gene amplification increases gene copies for study but doesn't allow precise editing of sequences.
Option c is incorrect because DNA fingerprinting identifies individuals through genetic patterns but doesn't edit or correct genes.
Option d is incorrect because chromosome painting visualizes chromosomes for diagnosis but cannot edit genetic sequences directly.

Correct Answer: Anteroposterior patterning

Polydactyly results from defective anteroposterior patterning during limb development, causing formation of extra digits beyond normal number.
Option a is incorrect because cell division timing affects growth rate but not the specific pattern of digit formation.
Option c is incorrect because neural tube closure defects cause spinal and brain malformations, not extra finger development.
Option d is incorrect because organ differentiation affects internal organs rather than the specific limb patterning causing polydactyly.

Correct Answer: Individual genetic variations

Genetic variations affect how individuals metabolize medications, making personalized dosing based on genetics more effective and safer.
Option a is incorrect because insurance requirements are administrative factors, not scientific reasons for genetic testing in medicine.
Option b is incorrect because generic drug availability is an economic factor unrelated to genetic influences on drug metabolism.
Option d is incorrect because hospital protocols are standardized procedures, not personalized genetic factors affecting drug responses.