PRINCIPLES OF MEDICINE MIDTERM EXAM Flashcards
most common malignant tumor of the oral cavity?
Squamous cell carcinoma
most common histological type of oral cancer is:
Squamous cell carcinoma
hallmarks of cancer allows cancer cells to divide indefinitely?
Enabling replicative immortality
Dysplasia is best described as
A pre-cancerous condition with abnormal cell appearance and disorganized tissue architecture
A tumor is composed of both parenchyma and stroma. What is the primary role of the parenchyma in a tumor?
It determines the biological behavior and name of the tumor
A pre-cancerous oral lesion appearing as a white patch on the mucosa is called:
Leukoplakia
A cancer that is confined to its tissue of origin, without lymph node involvement or metastasis, is classified as
Stage I
Which of the following is the main hallmark of neoplasia?
Uncontrolled and persistent cell division
The two basic components of a tumor are:
Parenchyma and stroma
What is the role of the stroma in a tumor?
It carries the blood supply and provides structural support
What is the MAIN characteristic that distinguishes benign tumors from malignant tumors?
) Malignant tumors invade and metastasize, while benign tumors do not
Which hallmark of cancer allows malignant cells to spread to distant organs?
Activating invasion and metastasis
Which of the following statements regarding cancer is FALSE?
Cancer cells maintain their normal cell-to-cell adhesion and architecture
Which of the following is NOT a risk factor for oral cancer?
High vitamin C intake
Which statement about benign and malignant tumors is TRUE?
Benign tumors are well-differentiated and do not spread
A 55-year-old smoker with a long history of alcohol consumption develops a non-healing ulcer on the lateral border of the tongue. The lesion is persistent for more than three weeks and is firm on palpation. Which of the following is the most appropriate next step?
Perform a biopsy of the lesion for histopathologic examination
In the TNM staging system, what does ‘N’ represent?
Lymph node involvement
What is the final stage of the cell cycle, where actual cell division occurs?
M
Which of the following findings is most characteristic of hereditary spherocytosis?
Spherocytes on peripheral smear
Iron-deficiency anemia is most commonly caused by:
Hemorrhage
What is the primary defect in Chronic Granulomatous Disease (CGD)?
Defective oxidative (respiratory) burst
Which anticoagulant specifically targets the intrinsic coagulation pathway?
Heparin
Which of the following is NOT a stage of hemostasis?
Coagulation degradation
Which of the following best describes the primary function of hemoglobin in red blood cells?
Transporting oxygen from the lungs to tissues and facilitating carbon dioxide removal
Prothrombin Time (PT) assesses
Extrinsic pathway
Which clotting factor is absent in hemophilia A
Factor VIII
Aplastic anemia is characterized by:
Decreased production of RBCs, WBCs, and platelets
What does an INR of greater than 5 indicate?
Increased risk of bleeding
Which laboratory test is the gold standard for diagnosing CGD?
Flow cytometric oxidative (respiratory) burst assay
Which type of anemia is characterized by large, immature RBCs?
Megaloblastic anemia
Which white blood cell type is most abundant in a normal blood smear?
. Neutrophils
A high eosinophil count suggests:
Parasitic infection
What hormone regulates RBC production?
. Erythropoietin
What is the primary function of blood?
Transport of gases, nutrients, and waste
B. Regulation of body temperature
C. Defense against infections
D. (All of the above)
Hodgkin lymphoma is characterized by the presence of:
Reed-Sternberg cells
Which of the following is NOT a component of blood?
Myosin
Which of the following best differentiates Gram-positive from Gram-negative bacteria?
The retention of crystal violet dye due to a thick peptidoglycan layer
Dermatophytes require which of the following for survival?
Keratin
An infectious agent that causes severe disease but does not easily spread from host to host would be described as having:
High virulence, low infectivity
Which of the following is a hallmark sign of sepsis?
Hypotension, organ failure, and shock
Tinea capitis is primarily diagnosed through:
Examination of plucked hairs on potassium hydroxide (KOH) wet mount
Case: A new strain of influenza virus spreads rapidly among a population but causes only mild symptoms in most infected individuals. Scientists analyzing the virus note that almost everyone exposed develops an infection, but severe complications are rare.
Which of the following best describes this new strain?
High infectivity, low virulence
The development of acute necrotizing ulcerative gingivitis is most strongly associated with which of the following conditions?
Poor oral hygiene and stress
Which of the following is a defining characteristic of obligate intracellular bacteria?
They require host cells for replication and survival.
Which of the following statements about dermatophytoses is FALSE?
They primarily affect internal organs.
Ludwig’s angina is a serious bacterial infection primarily affecting which anatomical regions?
Sublingual, submandibular, and submental spaces
Case: A 5-year-old child develops a high fever, cough, and runny nose. A week earlier, he had attended a birthday party where another child was later diagnosed with measles. The physician explains that measles spreads through airborne particles that can linger in the air for hours.
What mode of transmission is responsible for the spread of measles in this case?
Aerosol transmission
Case: A 23-year-old woman presents with painful urination, frequent urge to urinate, and lower abdominal discomfort. A urinalysis reveals elevated white blood cells and bacteria.
What type of infection is most likely responsible for her symptoms?
Urinary tract infection (UTI)
A patient develops a fungal infection after sharing contaminated towels. This mode of transmission is:
Indirect contact
The ability of an infectious agent to survive outside the host in adverse conditions is referred to as:
Survivability in the environment
Case: A 55-year-old man with poorly controlled diabetes presents with white, curd-like patches on his tongue and inner cheeks that can be scraped off, revealing red, inflamed tissue beneath. He reports a burning sensation in his mouth.
What is the most likely cause of his condition?
Oral candidiasis (thrush)
Which of the following correctly describes the sequence of events required for a microbe to establish infection?
Contamination → Adherence → Colonization → Invasion → Pathogenic Effects
Which of the following is a hallmark sign of sepsis?
Hypotension, organ failure, and shock
The development of acute necrotizing ulcerative gingivitis is most strongly associated with which of the following conditions?
Poor oral hygiene and stress
A patient with a history of HIV presents with white patches on the buccal mucosa that can be scraped off. The most likely diagnosis is:
Candidiasis
Oral candidiasis commonly occurs due to:
Overuse of antibiotics or immunosuppressive drugs
Which characteristic of an infectious agent refers to its ability to cause disease in a host?
Pathogenicity
Which of the following is an example of indirect transmission?
A person contracts influenza after shaking hands with an infected individual
A 72-year-old man with a history of diabetes is admitted to the ICU with confusion, low blood pressure, and rapid breathing. His blood tests show a very high white blood cell count and elevated lactate levels. Despite antibiotic therapy, his condition worsens, leading to organ dysfunction.
Septic shock
Which microbial infection is caused by Candida albicans and commonly presents as white patches on the oral mucosa?
Oral candidiasis (thrush)
