Lymphatic Structures Overview

Study Notes

Lymphatic Structures

Lymph Nodes: Small, bean-shaped organs that filter lymph fluid, containing immune cells to fight infections.
- Cervical: Located in the neck.
- Axillary: Located in the armpit.
- Thoracic: Located in the chest.
- Abdominopelvic: Located in the abdomen and pelvis.
- Intestinal: Located in the small intestine.
- Inguinal: Located in the groin.
- Popliteal: Located behind the knee.
Jugular Trunks: Collect lymph from the head and neck.
Subclavian Trunks: Collect lymph from the upper limbs and chest.
Bronchomediastinal Trunks: Collect lymph from the chest and lungs.
Intercostal Trunks: Collect lymph from the chest wall.
Lumbar Trunks: Collect lymph from the lower limbs and abdomen.
Intestinal Trunks: Collect lymph from the intestines.
Cisterna Chyli: A large, sac-like structure that collects lymph from the lower body.
Right Lymphatic Duct: Drains lymph from the right side of the body, including the right arm, right side of the head and neck, and right side of the chest.
Thoracic Duct: Drains lymph from the rest of the body.

Respiratory Structures

Nose: The entry point for air.
- External nares: Nostrils, the openings of the nasal cavity.
- Nasal vestibule: The entryway to the nasal cavity.
- Nasal cavity: The space within the nose, lined with mucous membrane to filter and warm the air.
  - Palatine tonsils: Lymphoid tissue located in the back of the throat; protects against pathogens.
  - Lingual tonsils: Lymphoid tissue located at the base of the tongue; protects against pathogens.
  - Pharyngeal tonsil (adenoid): Lymphoid tissue located in the nasopharynx; protects against pathogens.
Pharynx: A muscular tube that carries both air and food.
- Nasopharynx: The uppermost part of the pharynx, behind the nasal cavity.
- Oropharynx: The middle part of the pharynx, behind the mouth.
- Laryngopharynx: The lowermost part of the pharynx, connected to the larynx.
Larynx: A cartilaginous structure located in the neck, responsible for voice production.
- Epiglottis: A flap of cartilage that closes off the airway during swallowing, preventing food from entering the trachea.
- Glottis: The opening between the vocal cords.
- Thyroid cartilage: The "Adam's apple," a large cartilage that shields the larynx.
- Cricoid cartilage: A ring-shaped cartilage that supports the trachea.
- Vocal cords: Elastic tissues that vibrate to produce sound.
- Vestibular folds: False vocal cords, which help in vocalization but do not vibrate.
Trachea: A tube that carries air to the lungs.
- Cartilaginous rings: C-shaped rings that provide structural support to the trachea.
- Carina: A ridge that divides the trachea into the right and left bronchi.
- Trachealis: A smooth muscle that allows the trachea to expand and contract.
Bronchial Tree: A branching network of tubes that carries air from the trachea to the lungs.
- Primary bronchi: The two main branches of the trachea, one for each lung.
- Secondary bronchi: Branches of the primary bronchi, serving different lobes of the lung.
- Tertiary bronchi: Further branches of the secondary bronchi, leading to bronchioles.
- Bronchiole: Smallest tubes in the bronchial tree, eventually leading to alveoli.
- Microscopic structures:
  - Terminal bronchiole: Last part of the conducting zone, before starting the respiratory zone.
  - Respiratory bronchiole: Initial part of the respiratory zone, with alveoli starting to appear along the tube walls.
  - Alveolar duct: Small, air-filled passages that branch off respiratory bronchioles and lead to alveoli.
  - Alveolar sac: Cluster of alveoli at the end of the alveolar duct.
  - Alveolus: Tiny, air-filled sacs where gas exchange occurs.