Lymphatic and Respiratory Systems Review

Comprehensive vocabulary flashcards covering the lymphatic and respiratory systems, including cell types, immune responses, and lung volumes.

Functions of the Lymphatic System

Returns excess tissue fluid to the bloodstream, absorbs fats from the digestive tract, and defends the body against pathogens.

Lymph

Excess interstitial fluid with fewer proteins than plasma.

Primary Lymphatic Organs

Red bone marrow and thymus.

Red Bone Marrow

Produces blood cells and matures B cells.

Thymus

The site where T cells mature.

Secondary Lymphatic Organs

Lymph nodes, spleen, tonsils, and MALT (lymphatic nodules) which filter lymph or blood and serve as sites for immune responses.

Lymphatic Capillaries

Vessels with thin walls and overlapping endothelial cells that form one-way valves.

Lymphatic Valves

Structures that prevent backflow and keep lymph moving toward the heart.

Mechanisms of Lymph Movement

Skeletal muscle contractions, respiratory movements, and smooth muscle contractions in lymphatic vessels.

MALT

Stands for Mucosa-Associated Lymphatic Tissue; located in the digestive, respiratory, urinary, and reproductive tracts.

Peyer’s Patches

Lymphatic nodules located in the ileum of the small intestine.

Lymph Node vs. Lymph Nodule

Lymph nodes are encapsulated organs, while lymph nodules are nonencapsulated collections of lymphatic tissue.

Tonsils

Three types of lymphatic tissue including the Pharyngeal (adenoids), palatine, and lingual tonsils.

Palatine Tonsils

Tonsils located on each side of the oropharynx.

Pharyngeal Tonsils

Tonsils located in the nasopharynx.

Lingual Tonsils

Tonsils located at the base of the tongue.

Afferent vs. Efferent Vessels

Afferent vessels bring lymph into the node; efferent vessels carry filtered lymph away.

Reticular Fibers

Fibers in lymph nodes that trap foreign material and microorganisms.

Innate Immunity

Nonspecific immunity present at birth that responds immediately to threats.

Adaptive Immunity

Specific immunity that develops after exposure and possesses memory.

Physical Barriers

Components of innate immunity such as skin, mucus, cilia, tears, and saliva.

Interferons

Proteins that protect nearby cells from viral infection.

Membrane Attack Complex (MAC)

Complement proteins that punch holes in bacterial membranes.

Lysozyme

An enzyme that breaks down bacterial cell walls.

Chemotaxis

The movement of white blood cells toward a site of infection.

Phagocytosis

The process of engulfing and digesting pathogens or debris.

Neutrophils

First responder white blood cells that phagocytize bacteria.

Lymphocytes

White blood cells consisting of B cells (produce antibodies) and T cells (attack infected cells).

Monocytes

White blood cells that become macrophages and perform phagocytosis.

Eosinophils

White blood cells that fight parasites and reduce allergic reactions.

Basophils

White blood cells that release histamine and heparin.

Innate Immunity White Blood Cells

Includes neutrophils, monocytes/macrophages, eosinophils, basophils, and natural killer cells.

Adaptive Immunity White Blood Cells

Includes B cells and T cells.

Monocyte vs. Macrophage

Monocytes circulate in the blood, while macrophages are monocytes that have entered tissues.

Basophil vs. Mast Cell

Basophils are found in blood, while mast cells are found in tissues.

Natural Killer (NK) Cell

An innate immunity lymphocyte that destroys virus-infected and cancer cells.

Signs of Inflammation

Redness, heat, swelling, pain, and loss of function.

Systemic Inflammation

Body-wide inflammation characterized by fever and increased white blood cells.

Antigen

A substance that triggers an immune response.

Antibody

A protein produced by B cells that binds to a specific antigen.

Tolerance

The immune system’s ability to ignore self-antigens.

Costimulation

A second signal needed to fully activate T cells.

Primary vs. Secondary Immune Response

The primary response is the first exposure (slower/weaker); the secondary response is faster and stronger due to memory cells.

Helper T Cells

Cells that activate B cells, cytotoxic T cells, and macrophages.

Cytotoxic T Cells

Cells that kill infected or abnormal cells.

Regulatory T Cells

Cells that suppress immune responses and prevent autoimmunity.

Active vs. Passive Immunity

Active immunity involves the body producing its own antibodies; passive immunity involves receiving antibodies from another source.

Natural vs. Artificial Active Immunity

Natural active comes from recovering from infection; artificial active comes from vaccination.

Natural vs. Artificial Passive Immunity

Natural passive is passed from mother to baby; artificial passive is received by injection.

Ventilation

The movement of air into and out of the lungs.

External Respiration

The exchange of $O_2$ and $CO_2$ between the alveoli and the blood.

Internal Respiration

The exchange of $O_2$ and $CO_2$ between the blood and body tissues.

Upper Respiratory Tract

Consists of the nose, nasal cavity, paranasal sinuses, and pharynx.

Lower Respiratory Tract

Consists of the larynx, trachea, bronchi, bronchioles, alveolar ducts, alveoli, and lungs.

Conducting Zone

The portion of the respiratory tract that moves air but does not perform gas exchange (nose through terminal bronchioles).

Respiratory Zone

The portion of the respiratory tract where gas exchange occurs (respiratory bronchioles, alveolar ducts, and alveoli).

Pharynx

A passageway for both air and food divided into the nasopharynx, oropharynx, and laryngopharynx.

Larynx

Maintains an open airway, produces sound, and prevents food from entering the airway.

Epiglottis

Structure that closes over the larynx during swallowing to protect the airway.

Trachea

Conducts air to the bronchi and uses cilia and mucus to clean the air.

Carina

The ridge where the trachea divides into the right and left bronchi; sensitive area for the cough reflex.

Quadrangular membrane

An area that helps trigger the cough reflex.

Bronchioles

Small airways that regulate airflow by changing their diameter.

Pleura

The visceral pleura covers the lung, the parietal pleura lines the thoracic cavity, and the pleural cavity contains fluid.

Right Lung

Contains three lobes divided by horizontal and oblique fissures.

Left Lung

Contains two lobes divided by an oblique fissure; has a cardiac notch for the heart.

Type I Pneumocytes

Cells that form the thin walls of alveoli where gas exchange occurs.

Type II Pneumocytes

Cells that produce surfactant to reduce surface tension and prevent alveolar collapse.

Surfactant

A substance that reduces surface tension to keep alveoli from collapsing.

Diaphragm

The main muscle of inspiration that flattens to increase thoracic volume.

Intercostal Muscles

External intercostals elevate ribs (inspiration); internal intercostals depress ribs (forced expiration).

Tidal Volume ($TV$)

The amount of air inhaled or exhaled during normal breathing.

Inspiratory Reserve Volume ($IRV$)

The extra air that can be inhaled after a normal breath.

Expiratory Reserve Volume ($ERV$)

The extra air that can be exhaled after a normal exhalation.

Residual Volume ($RV$)

The amount of air remaining in the lungs after maximum exhalation.

Vital Capacity ($VC$)

The maximum air exhaled after maximum inhalation, calculated as $TV + IRV + ERV$.

Total Lung Capacity ($TLC$)

The total amount of air the lungs can hold, calculated as $VC + RV$.

Carbonic Acid Equation

$$CO_2 + H_2O \rightleftharpoons H_2CO_3 \rightleftharpoons H^+ + HCO_3^-$$

Respiratory Pressure Dynamics

Air moves in when intrapulmonary pressure is lower than atmospheric; air moves out when intrapulmonary pressure is greater than atmospheric.

Partial Pressure of Oxygen ($PO_2$)

The concentration of oxygen that drives oxygen diffusion.

Medulla Oblongata

The part of the brain that controls the basic rhythm of breathing.

Pons

The part of the brain that modifies and smooths the breathing pattern.

Hering-Breuer Reflex

A protective reflex where stretch receptors in the lungs inhibit inspiration to prevent overinflation.

Aging Effects on Respiratory System

Decreased lung elasticity, weaker muscles, reduced vital capacity, and less efficient gas exchange.