Microorganisms
Briefly explain how viruses and bacteria differ in their replication.
Viruses replicate inside host cells; bacteria replicate independently
Which cell arrives at the site of inflammation 2–3 days later and plays a role in allergic responses and parasitic defense?
Eosinophils
Which cells are primarily responsible for capturing, processing, and presenting antigens to T cells to initiate an adaptive immune response?
Dendritic cells
B cells
Erythrocytes
Monocytes
Dendritic Cells
B Cells could be another option, but are not as efficient as dendritic cells. B cells' primary function is to produce antibodies
A 45-year-old patient has been diagnosed with long-standing hypertension. Over time, the patient’s left ventricular cardiac muscle cells have increased in size to compensate for the increased workload. Which cellular adaptation best describes this condition?
Hypertrophy
Atrophy
Hyperplasia
Dysplasia
Hypertrophy
A patient presents with redness, swelling, and pain in a localized area. Which sequence best describes the cellular events occurring?
Adhesion → rolling → margination
Transmigration → rolling → adhesion
Margination → rolling → adhesion → transmigration
Chemotaxis → margination → phagocytosis
Margination → rolling → adhesion → transmigration
Why can infections caused by Gram-negative bacteria lead to septic shock more often than those caused by Gram-positive bacteria?
They continuously secrete exotoxins during replication
They lack a cell wall, making them resistant to antibiotics
Endotoxins in their outer membrane are released during lysis, provoking a strong inflammatory response
They divide more rapidly than Gram-positive bacteria
Endotoxins in their outer membrane are released during lysis, provoking a strong inflammatory response
What feature best distinguishes purulent inflammation from serous inflammation?
Predominance of neutrophils and pus formation
Describe innate immunity vs acquired immunity.
Innate immunity is ingrained and nonspecific against multiple pathogens at any given time. Aquired or adaptive immunity is developed from previous exposure to specific pathogens.
A smoker develops a change in the cells lining their airways, where normal columnar cells are replaced by squamous cells. Which adaptive process is most likely occurring?
Hyperplasia
Atrophy
Metaplasia
Dysplasia
Metaplasia
A patient presents with fever, elevated white blood cell count, and right lower quadrant abdominal pain. What is the most appropriate initial diagnostic test?
Abdominal ultrasound
CT scan of the abdomen
Complete blood count (CBC)
Colonoscopy
Abdominal ultrasound
Which step of viral replication involves the virus using the host cell’s machinery to produce viral proteins and genomes?
Replication. During the replication phase, the virus hijacks and overtakes the host cell’s organelles (ribosomes, enzymes, and nucleotides) to produce viral proteins and replicate its genome.
Which inflammatory mediator is released mainly from mast cells and causes vasodilation and increased vascular permeability in the early stages of inflammation?
Histamine
Prostaglandins
Leukotrienes
Bradykinin
Histamine
Which WBC mature in the Bones?
B cells
A patient twists their ankle and develops mild swelling in the surrounding tissue. Which reversible cellular change is most likely occurring?
Cell swelling
Nuclear fragmentation
Mitochondrial rupture
Chromatin dissolution
Cellular Swelling
Which white blood cell is the first to arrive at the site of a bacterial infection and is primarily responsible for phagocytosis?
Neutrophils
Eosinophils
Lymphocytes
Basophils
Neutrophils
A bacterium is Gram-positive and forms chains of cocci. Which genus is most likely?
Staphylococcus
Streptococcus
Escherichia
Bacillus
Streptococcus
hich cytokines are primarily responsible for triggering the hypothalamus to raise body temperature during an inflammatory response?
IL-6 and IFN-γ
IL-1 and TNF-α
Prostaglandins and Bradykinin
Histamine and Complement Proteins
IL-1 and TNF-α
What is the main role of helper T cells in the immune response?
To activate B cells and other immune cells by releasing cytokines
They play a key role in orchestrating the adaptive immune response by releasing cytokines that stimulate B cells to produce antibodies, as well as activate cytotoxic T cells, and recruit macrophages and other immune cells.
A cell is examined under the microscope after injury. Which finding would indicate irreversible cell damage rather than reversible?
Cell swelling
Nuclear fragmentation
Plasma membrane blebbing
Ribosome detachment
Nuclear Fragmentation
What is the most accurate description of the difference between homeostasis and steady-state?
- Homeostasis involves energy use; steady state does not.
- Steady state is feedback-driven; homeostasis is not.
- Homeostasis uses feedback mechanisms to maintain stability
- They are interchangeable terms.
Homeostasis uses feedback mechanisms to maintain stability
Why might a fungal infection be more difficult for the immune system to fight off?
Fungi have complex cell walls and an eukaryotic (true nucleus) structure similar to human cells, making them more difficult to identify from self.
Which inflammatory mediator is produced as an inactive precursor and, once activated, contributes to vasodilation, increased vascular permeability, and pain at the site of injury?
Histamine
Bradykinin
Prostaglandin
Tumor necrosis factor (TNF)
Bradykinin
During an inflammatory response, monocytes leave the bloodstream and differentiate into macrophages. What is the primary role of these macrophages at the site of infection?
Produce antibodies to neutralize pathogens
Directly kill virus-infected cells
Phagocytose pathogens and present antigens to T cells
Release histamine to increase vascular permeability
Phagocytose pathogens and present antigens to T cells. They do not produce antibodies or release histamine, and cytotoxic killing is mainly done by killer t or cytotoxic t cells.
On a Pap smear, cervical cells are found to have irregular shapes, variable sizes, and disorganized arrangement. Which adaptive process does this represent?
Metaplasia
Hyperplasia
Dysplasia
Atrophy
Dysplasia
Why might procalcitonin be preferred over CRP in managing antibiotic therapy?
More sensitive and specific to the presence of bacterial infections
It declines rapidly with effective treatment