ANAPHY LECTURE (FINALS - RESPIRATORY SYSTEM)

Gas exchange

The physiological process overseen by the respiratory system involving oxygen and carbon dioxide transfer between the blood and the external environment.

Alveoli

The specific structural site in the lungs where gas exchange exclusively takes place.

Air Passageways

The collective term for the respiratory structures that purify, warm, and humidify incoming air before it reaches the lungs.

Cardiovascular system

Name the body system that shares responsibility with the respiratory system for supplying oxygen and removing carbon dioxide.

Cellular respiration

The metabolic process requiring oxygen delivery to cells.

Moist

The physical condition/characteristic of the surface of the lungs.

• Oxygen

• Carbon dioxide

Enumerate the two (2) gases exchanged between the blood and external environment:

• Purify

• Warm

• Humidify

Enumerate the three functions performed by the air passageways on incoming air:

Enumerate the 6 main organs of the respiratory system:

Trachea

A vacuum-like tube surrounded by circular cartilage rings that keep the airway open.

• Right lung: 3 lobes

• Left lung: 2 lobes

Enumerate the number of lobes present in each lung:

Sinuses

Air-filled cavities lined with mucous membranes located within the bones of the skull.

Frontal sinus

The sinus located within the frontal bone, directly above the eyes.

Sphenoid sinus

The sinus located deep inside the sphenoid bone, behind the nasal cavity.

Maxillary sinuses

The sinuses situated inside the cheekbones or maxilla.

Ethmoid sinuses

The collection of multiple small air cells located between the eyes.

• Frontal sinus

• Sphenoid sinus

• Maxillary sinuses

• Ethmoid sinuses

Enumerate the four paranasal sinuses:

Olfactory receptors

Receptors located in the mucosa on the superior surface of the nasal cavity.

Respiratory mucosa

The specialized tissue lining the majority of the nasal cavity that moistens air and traps incoming foreign particles.

• Moistens air

• Traps incoming foreign particles

Enumerate the two functions of the respiratory mucosa in the nasal cavity:

Conchae

Projections on the lateral walls of the nasal cavity.

Palate

The structure that separates the nasal cavity from the oral cavity.

Hard palate

The anterior bony part of the palate.

Soft palate

The posterior muscular part of the palate.

• Increases surface area

• Increases air turbulence within the nasal cavity

Enumerate the two functions of the nasal conchae:

• Anterior hard palate (bone)

• Posterior soft palate (muscle)

Enumerate the two parts of the palate and their corresponding tissue compositions:

Paranasal sinuses

Cavities located within bones surrounding the nasal cavity.

• Frontal bone

• Sphenoid bone

• Ethmoid bone

• Maxillary bone

Enumerate the four bones containing paranasal sinuses that surround the nasal cavity:

• Lighten the skull

• Act as resonance chambers for speech

• Produce mucus that drains into the nasal cavity

Enumerate the three functions of the paranasal sinuses:

Pharynx (Throat)

The muscular passage extending from the nasal cavity to the larynx.

Nasopharynx

The superior region of the pharynx located behind the nasal cavity.

Oropharynx

The middle region of the pharynx located behind the mouth.

Laryngopharynx

The inferior region of the pharynx attached to the larynx.

• Nasopharynx

• Oropharynx

• Laryngopharynx

Enumerate the three regions of the pharynx in order:

• Oropharynx

• Laryngopharynx

Enumerate the two regions of the pharynx that serve as common passageways for both air and food:

Auditory tubes

The structures that enter the nasopharynx.

Eustachian tube

The structure that equalizes pressure in the ear.

Pharyngeal tonsil (adenoids)

The tonsil located specifically in the nasopharynx.

Palatine tonsils

The tonsils located in the oropharynx.

Lingual tonsils

The tonsils located at the base of the tongue.

• Pharyngeal tonsil (adenoids) – in the nasopharynx

• Palatine tonsils – in the oropharynx

• Lingual tonsils – at the base of the tongue

Enumerate the three tonsils found in the pharynx and their respective locations:

Larynx

The structure commonly known as the voice box.

Epiglottis

The spoon-shaped flap of elastic cartilage located within the larynx.

• Routes air and food into proper channels

• Plays a role in speech

Enumerate the two primary functions of the larynx:

• Eight rigid hyaline cartilages

• One spoon-shaped flap of elastic cartilage (epiglottis)

Enumerate the cartilage components that make up the larynx:

Thyroid cartilage

The largest hyaline cartilage that protrudes anteriorly as the Adam's apple.

Thyroid cartilage

The structure that protects the vocal cords.

Epiglottis

The structure forming the superior opening of the larynx that routes food to the larynx/esophagus and air toward the trachea.

• Thyroid cartilage

• Epiglottis

Enumerate the two main structures of the larynx:

• Largest hyaline cartilage

• Protrudes anteriorly (Adam's apple) (Note: protects the vocal cords)

Enumerate two characteristics/functions of the thyroid cartilage:

Vocal cords (vocal folds)

Structures within the larynx that vibrate with expelled air to create sound or speech.

Glottis

The opening located between the vocal cords.

Trachea (Windpipe)

The respiratory tube commonly known as the windpipe that connects the larynx with the bronchi.

Ciliated mucosa

The specialized tissue lining the trachea that beats continuously to move mucus away from the lungs.

C-shaped hyaline cartilage

The specific structure reinforcing the walls of the trachea to keep the airway open.

• Beat continuously in the opposite direction of incoming air

• Expel mucus loaded with dust and other debris away from lungs

Enumerate the two main functions of the cilia/ciliated mucosa lining the trachea:

Primary bronchi

The structures formed by the division of the trachea.

Hilus

The medial depression on the lung where primary bronchi enter.

• Wider

• Shorter

• Straighter

Enumerate the three characteristics of the right primary bronchus in comparison to the left:

Organs that occupy most of the thoracic cavity.

Apex

The superior portion of the lungs located near the clavicle.

Base

The inferior portion of the lungs that rests on the diaphragm.

Fissures

Grooves or divides that separate each lung into lobes.

• Apex (superior portion near the clavicle)

• Base (inferior portion resting on the diaphragm)

Enumerate the two main structural divisions/portions of the lungs and their location:

Pulmonary (visceral) pleura

The serous membrane layer that directly covers the surface of the lung.

Parietal pleura

The serous membrane layer that lines the inner wall of the thoracic cavity.

Pleural fluid

The fluid located in the space between the pleural membranes that reduces friction and allows smooth gliding.

• Pulmonary (visceral) pleura

• Parietal pleura

• Pleural fluid

Enumerate the two layers of pleura and the fluid found between them:

Pleural space

The space located between the parietal pleura and visceral pleura.

Parietal pleura (Costal part)

The specific part of the parietal pleura that adheres to the inner surface of the ribs and intercostal muscles.

• Hemothorax

• Pneumothorax

• Hydrothorax

Enumerate three clinical conditions associated with the accumulation of fluid, blood, or air within the pleural space:

Enumerate the five divisions of the respiratory tree in sequential order:

Bronchioles

The smallest branches of the bronchi.

Reinforcing cartilage

The supportive structural component present in all respiratory tree branches except the smallest ones.

Alveoli

The terminal structures where terminal bronchioles end.

Respiratory Zone

The zone that serves as the site of gas exchange.

Alveolar sac

A cluster or group of alveoli that share a common opening into an alveolar duct.

• Respiratory bronchioli

• Alveolar duct

• Alveoli

Enumerate the three structures that make up the Respiratory Zone:

Gas exchange

The primary function occurring at the level of the alveoli.

Respiratory Membrane

The structure formed by alveolar and capillary walls that acts as the air-blood barrier.

Thin squamous epithelial layer

The tissue layer lining the alveolar walls within the respiratory membrane.

Pulmonary capillaries

The blood vessels that cover the external surfaces of the alveoli.

Gas Exchange

Gas crosses the respiratory membrane by diffusion.

Diffusion

Process by which gas crosses the respiratory membrane.

Macrophages

Cells that add protection in the alveoli.

Surfactant

Substance that coats gas-exposed alveolar surfaces.

• Oxygen enters the blood

• Carbon dioxide enters the alveoli

Enumerate the movement of gases across the respiratory membrane during diffusion.

• Gas crosses the respiratory membrane by diffusion

• Macrophages add protection

• Surfactant coats gas-exposed alveolar surfaces

Enumerate key features/protective mechanisms of gas exchange in the alveoli.

Pulmonary ventilation

Moving air in and out of the lungs.

External respiration

Gas exchange between pulmonary blood and alveoli.

Respiratory gas transport

Transport of oxygen and carbon dioxide via the bloodstream.

Internal respiration

Gas exchange between blood and tissue cells in systemic capillaries.

• Pulmonary ventilation

• External respiration

• Respiratory gas transport

• Internal respiration

Enumerate the two events of respiration:

Mechanics of Breathing / Pulmonary Ventilation

Completely mechanical process that depends on volume changes in the thoracic cavity.

Volume changes in the thoracic cavity

The driver of pressure changes during breathing that ultimately leads to the flow of gases to equalize pressure.

• Diaphragm contracts downward

• Thoracic cavity expands

• Lung pressure drops

• Air enters

Enumerate the sequence of events during inhalation:

Inspiration

Flow of air into lung.

Expiration

Air leaving lung.

• Inspiration

• Expiration

Enumerate the two phases of pulmonary ventilation.

Inspiration

Diaphragm and intercostal muscles contract, leading to an increase in thoracic cavity size and intrapulmonary volume.