BIOL 2252: Respiratory System & Immune System UNIT 3

What structure divides the nasal cavity into right and left parts?

nasal septum

What is the largest cartilage in the larynx?

thyroid cartilage

What function besides lubrication does pleural fluid serve?

holds the visceral and parietal pleural membranes together

Which region is lined with pseudostratified ciliated columnar epithelium?

nasopharynx

What is the correct airflow order from bronchi to alveoli?

terminal bronchiole → respiratory bronchiole → alveolar duct → alveolus

According to Boyle's law, as volume increases, pressure…

decreases

During expiration, alveolar pressure is…

greater than barometric pressure

What happens to airflow during an asthma attack?

decreases

What happens to lungs during pneumothorax?

collapse

What is the function of surfactant?

decreases surface tension of alveolar fluid

If lung compliance increases, lung expansion is…

easier

Which lung capacity is the largest?

vital capacity

Which volume represents air available for gas exchange each minute?

alveolar ventilation

Which respiratory volume remains in lungs after forced expiration?

residual volume

What is the name of the muscle primarily responsible for breathing?

diaphragm

What structure prevents food from entering the trachea?

epiglottis

What is the function of the nasal conchae?

create turbulence in inhaled air

What tissue type lines alveoli for gas exchange?

simple squamous epithelium

What respiratory cells secrete surfactant?

type II alveolar cells (septal cells)

What is the function of alveolar macrophages?

remove debris and pathogens in alveoli

What part of the brain controls breathing rate?

medulla oblongata

Where is the respiratory control center located?

pons and medulla

What causes increased breathing rate during exercise?

increased CO₂ and hydrogen ion levels

What is the term for oxygen binding to hemoglobin?

oxygen loading

What enzyme facilitates CO₂ conversion in red blood cells?

carbonic anhydrase

Which direction does oxygen diffuse during gas exchange in lungs?

from alveoli to capillaries

Which immune system component is present at birth and nonspecific?

innate immunity

Which immune cell kills virus-infected and cancerous cells?

NK cells

What are the two main types of lymphocytes?

B cells and T cells

What protein messengers regulate immune activity?

cytokines

What is the function of interferons?

prevent viral replication in nearby cells

What organ is a primary lymphoid organ?

thymus

What is opsonization?

coating a pathogen to enhance phagocytosis

Which immune cell presents antigens to T cells?

dendritic cell

Which cell performs phagocytosis and is derived from monocytes?

macrophage

Which innate immune cells secrete histamine?

basophils and mast cells

Which line of defense involves skin and mucosal barriers?

first line of defense

Which line of defense involves fever and inflammation?

second line of defense

What is the term for programmed cell death initiated by NK cells?

apoptosis

What complement effect forms membrane pores in pathogens?

cytolysis

Which immune response is specific and slower to develop?

adaptive immunity

What is the role of helper T cells?

activate B cells and other immune cells

What do cytotoxic T cells do?

destroy infected or abnormal cells

What is the purpose of MHC molecules?

display antigens for recognition by T cells

What are antibodies produced by?

B cells (plasma cells)

Which antibody is the most abundant in blood?

IgG

Which antibody is found in secretions like saliva and tears?

IgA

What is the function of lymph nodes?

filter lymph and house immune cells

Which organ filters blood and recycles old red blood cells?

spleen

What is the function of the tonsils?

monitor pathogens entering through the mouth and nose

What is the effect of fever on pathogens?

inhibits growth and accelerates tissue repair