Anatomy- Lymphatic and Respiratory Systems

Lymph Vessels

Transports excess fluids from interstitial space back to blood; one-way; pump-less; open- circuit; highly permeable; low pressure; 3 layers

Lymph Vessels Layers

Outer Layer: adrentitia (connective tissue; supports and anchors vessels)

Middle Layer: smooth muscle cells

Inner Layer: simple squamous epithelium

Lymph Nodes

Lymph passed through these multiple times to filter out pathogens, debris, and cancer cells by immune cells;

House leukocytes: macrophages and lymphocytes;

Connective tissue capsule that pokes into center creating trabecular compartments, an outer cortex, and an inner medulla with large leukocyte population

Lymphatic System Functions

Drain excess interstitial fluid;

Transport dietary lipids and fat-soluble vitamins from the small intestine to the blood;

Offer protection against pathogens

Lymphatic Organs

Generation, training, and habituation of immune cells;

Primary: bone marrow and thymus

Secondary: lymph nodes, spleen, tonsils, gut-associated lymphoid tissue (GALT)

Lacteals

specific lymphatic vessels responsible for absorbing fluid, protein, and fats from digestive tract

Lymph Components

water, salts, proteins, lipids, WBCs, bacteria, cellular debris

Lymph Vessel Pathway

interstitial fluid space → lymphatic capillaries→ afferent vessels→ lymph nodes→ efferent vessels→ right lymphatic or thoracic duct→ subclavian veins→ superior vena cava

Right Lymphatic Duct

Collect from right side of head, thorax, and right arm; Dumps into the right subclavian vein

Thoracic Duct

Collects from lower half of body and left half of body via the cisterna chyli; Drains into left subclavian vein

Cisterna Chyli

Dilated sac that receives lymph from intestinal and lumbar lymphatic trunks

Lymphatic Capillaries

Little to no smooth muscle; lack adventitia; small

Red Bone Marrow

Hematopoietic tissue- produces erythrocytes, thrombocytes, and leukocytes;

Largely replaced with yellow bone marrow with growth/age;

Immunocompetence

Residence for memory B and T cells

Yellow Bone Marrow

Primarily adipocytes

Thymus

Capsule with 2 lobes each with an outer cortex and inner medullary;

Largest and most active when young- develops immunity and atrophies with age/development;

Thrombocytes that mature and gain immunocompetence here

Spleen

Filters blood: removes aged/damaged erythrocytes, pathogens, and cellular debris;

Reservoir for platelets and blood;

Site of lymphocyte proliferation;

Surveillance area for immune cells

Tonsils

Small, round masses of lymphoid tissue in the pharynx;

Pharyngeal/Adenoids, Palatine, and Lingual;

Contain immune cells that capture and destroy pathogens before they enter the body further

Gut Associated Lymphatic Tissue (GALT)

Traps and eliminates pathogens in the lymphatic tract;

Peyer’s Patches and Appendix

Peyer’s Patches

GALT

Round aggregates of lymphoid tissue within the mucosa and submucosal layers of the ileum of the small intestine

Appendix

Finger-like projection off of cecum of large intestine

Respiratory System Function

Gas exchange and pH balance

Pulmonary Ventilation

Air movement in and out of the lungs

External Respiration

Gas exchange between lungs and blood

Gas Transport

Carrying gases through the blood

Internal Respiration

Gas exchange between blood and systemic tissues

Conducting Zone

Gas transport;

Lined with respiratory epithelium (pseudostratified ciliated columnar with goblet cells);

Nose, pharynx, larynx, trachea, bronchi, lung

Nose

Filters allergens, dust, and pathogens from inhaled air;

Resonating chamber during speech;

Lined with olfactory receptors;

External nares, nasal cavity, nasal conchae, parasinal sinuses

Nasal Cavity

Superior portion of hard palate and nasal conchae;

Anterior: stratified squamous;

Deeper: mucus membrane (pseudostratified ciliated columnar with goblet cells) that moistens air and catches debris (cilia move toward pharynx for removal)

Even Deeper: connective tissue to warm air

Nasal Conchae

Ridges that increase surface area and create turbulence and spinning of the air→ pushes the air towards the mucus membrane

Parasinal Sinuses

4 pairs of hollow spaces in the skull around the nose and nasal cavity;

Frontal, ethmoid, sphenoid, and maxillary;

Decreases the bony mass of the skull;

Resonance chamber for speech;

Pseudostratified ciliated columnar with goblet cells

Pharynx

Nasopharynx (pseudostratified ciliated columnar), oropharynx (nonkeratinized stratified squamous), laryngopharynx (both);

Lined with mucus membrane;

Deep to the epithelia tissue: tonsils;

Pharyngeal/Eustachian Tubes: drain middle ear to the nasopharynx

Tonsils

Immunoprotection;

Pharyngeal/Adenoids (nasopharynx);

Palatine and Lingual (oropharynx)

Larynx

Lining is mostly pseudostratified ciliated columnar with goblet cells;

Directs air → trachea and food→ esophogus;

Involved with speech and sound production, also coughing;

Epiglottis covers opening of larynx (glottis) to prevent food/fluid from entering;

9 Hyaline Cartilages: includes thyroid cartilage, cricoid cartilage, and arytenoid cartilage

Thyroid Cartilage (Larynx)

Largest of larynx cartilages;

Protects vocal cords (nonkeratinized stratified squamous)

Cricoid Cartilage (Larynx)

Attachment site for muscles, cartilages, and ligaments involved with speech production;

Forms complete ring around superior border of trachea

Arytenoid Cartilage (Larynx)

Abduct and adduct vocal cords to change pitch;

Muscles controlling its movement innervated by vagus nerve

Trachea

C-shaped rings of hyaline cartilage;

Lined with pseudostratified ciliated columnar with goblet cells;

Mucus traps debris and pathogens;

Cilia beats upward to propel the mucus and trapped material to the pharynx for removal

Bronchi

Direct inspired air to lungs;

Right Primary: larger diameter, shorter, more vertical;

Primary→ secondary→ tertiary→ #- order segmental bronchi→ bronchioles→ terminal bronchioles (end of conducting zone)

Lungs

Apex: just deep and inferior to clavicles, narrow and superior portion;

Base: directly on and connected to diaphragm;

Cardiac Notch: indent on left lung to make room for the heart:

Pulmonary Pleura

Pulmonary Pleura Components/Layers

Visceral Pleura: directly on top of each lung;

Pleural Cavity: between layers, filled with pleural fluid;

Parietal Pleura: anchors lungs to thoracic cavity and superior portion of the diaphragm

Respiratory Zone

Gas exchange;

Respiratory bronchioles→ alveolar ducts→ alveolar sacs

Type I Alveolar Cells

Most alveoli;

Single layer simple squamous around empty space;

Deep is thin layer of elastic connective tissue;

Macrophages intermixed within alveolar spaces

Alveolar Pores

Join alveoli

Type II Alveolar Cells

Secrete surfactant

Surfactant

Complex of proteins and phospholipids that decrease surface tension and prevent alveoli collapse at end of expiration

Pulmonary Capillaries

Surround alveoli;

Simple squamous epithelial

Respiratory Membrane

Alveolar walls, pulmonary capillary walls, and the basement membrane between these walls;

Air- blood barrier;

Gas exchange

Breathing Muscles- Quiet Breathing

Diaphragm;

Inspiration: contracts inferiorly→ increased length and volume of thoracic chamber;

Expiration: relaxes→ decreased thoracic chamber size and volume

Breathing Muscles- Forced with Accessory Muscles

Inspiration: external intercostals, sternocleidomastoid, pectoralis minor, serratus anterior, scalenes; raises and widens ribs;

Expiration: internal intercostals, external abdominal obliques, internal obliques, transverse abdominis, rectus abdominis

Boyle’s Law

Volume and pressure are inversely proportional

Spirometry

Pulmonary function test that measures volumes of air inspired and expired as well as their speeds; measured with spirometer

Dalton’s Law of Proportional Pressures

Total pressure = sum of partial pressures

Henry’s Law

When gas and liquid are in contact, gas dissolves into the liquid in proportion to its solubility and partial pressure;

Increased partial pressure difference = more gas dissolving into the liquid and faster

Oxygemoglobin

Hemoglobin saturated with oxygen (4)

Hemoglobin Molecule Components

4 polypeptide units (Globins- 2 alpha and 2 beta in adults; each with 1 heme group with 1 iron)

Deoxyhemoglobin

Hemoglobin after exchanging oxygen;

Primed for carbon dioxide

Carbon Dioxide Transport

Dissolved in plasma (7-10%);

Chemically bound to hemoglobin (20%):

Converted to bicarbonate and hydrogen ions

Carbaminohemoglobin

4 carbon dioxides bound to hemoglobin

Haldane Effect

Hemoglobin without oxygen is more likely to bind to carbon dioxide

Carbon Dioxide Converted to Bicarbonate and Hydrogen Ions

When carbonic anhydrase is present carbon dioxide and water form carbonic acid;

Carbonic acid then splits to hydrogen ion and bicarbonate;

H+ binds to hemoglobin;

Chloride Shift: bicarbonate transported out of erythrocyte in exchange for Cl- from the plasma with facilitated diffusion; Bicarbonate diffuses in the plasma to be transported to the lungs

Oxygen- Hemoglobin Saturation Curve

Y-axis: % hemoglobin saturated with oxygen;

X-axis: pressure of oxygen in mmHg;

Effected By: tissue activity levels, temperature, blood pH levels

Tissue Activity Levels Influence on Oxygen-Hemoglobin Saturation Curve

Increased activity: use oxygen faster for ATP→ decreased oxygen pressure from 40 mmHg to 20 mmHg→ higher percentage of oxygen delivered

Temperature Influence on Oxygen-Hemoglobin Saturation Curve

Increased temperature: right shift in curve for metabolically active tissue due to increased oxygen delivered; limited change on lungs

Blood pH Levels Influence on Oxygen-Hemoglobin Saturation Curve

Decreased pH: right shift in curve for systemic tissues due to increased oxygen delivery (need oxygen for metabolism whose wastes lower pH); limited change on lungs;

Bohr Effect

Bohr Effect

Increased blood pH→ hemoglobin has increased affinity for oxygen