Human Anatomy & Physiology: Respiratory System Flashcards

Supply body with oxygen and dispose carbon dioxide.

Pulmonary Ventilation & External Respiration

Movement of oxygen from lung air to blood.

Movement of oxygen from lung air to blood & movement of carbon oxygen from blood to lung air

condiuts/passageways for air to reach sites for gas exchange.
-Nose
-Nasal Cavity
-Pharynx
-Larynx
-Trachea
-Bronchi & Branches

Actual sites of gas exchange
-respiratory bronchioles
-alveolar ducts
-alveoli

Provides airway for respiration
-moisten entering air
-warms entering air
-filters entering air
-houses olfactory receptors

Root (frontal bone)
Bridge (Nasal Bone)
Septal, Lateral, Alar Cartilages (Hyaline)
Alae (Dense Connective Tissue

Extends from nares (nostrils) to choanae (opening to pharynx). Floor of cavity is hard palate (anterior), muscular soft palate (posterior). Hairs extend into nasal vestibule to filter coarse particles from entering air.

Mucous membrane lining superior region; has smell recptors

Lines remainder of nasal cavity.
-ciliated, pseudostratified columnar epithelium
-goblet cells with mucous and serous glands
-mucus has lysozyme and defensins that trap dirt and kill bacteria

Superior, Middle, Inferior protrusions that create turbulence in inspired air

Throat

Respiratory Passageway = nasal cavity to larynx
Digestive Passageway = oral cavity to esophagus

Nasopharynx, Oropharynx, Laryngopharynx

Connects pharynx to trachea.

Controls passage of air and food to proper channels

Spoon shaped elastic cartilage extending from posterior tongue to anterior rim of thyroid cartilage.
-covers laryngeal inlet during swallowing...prevents food from trachea

Opening between vocal folds, lets air pass through to trachea

Flexible tube from larynx inferiorly branching into two main bronchi. Has sensory receptors that detect foreign particles and has a cough reflex.
-cleans, warms, moistens passing air

1. Mucosa
2. Submucosa
3. Cartilage
4. Adventitia

Pseudostratified ciliated epithelium with goblet cells and sweeps mucus

CT layer around mucosa

C shaped rings of hyaline cartilage around anterior and side
-allows flexing and prevents collapse of tube lumen

Outermost layer of CT

Division of Trachea, each enters respective lung at hilum
PRIMARY

Ridge formed by most inferior tracheal cartilage
-radiological landmark that seperates right and left main bronchi
-sensitive to mechanical stimulation, powerful cough reflex.

Three in right lung and two in the left lung
-supply each lobe of lungs
SECONDARY

Branching of lobar/secondary bronchi

Passageways less than 1 mm diameter

Beginning of Respiratory Zone- where gas exchange occurs

Rings of smooth muscle cells and CT fibers

Clusters of alveoli attached to alveolar ducts

Microscopic air-filled chambers at end of bronchial tree
-walls are simple squamous epithelium
-external surface intimately associated with pulmonary capillaries
-main sites of gas exchange

In respiratory zone, layers through which gas exchange occurs by simple diffusion composed of wall of alveolus and wall of pulmonary capillary

Mostly simple squamous epithelium (type I cells)
-also has type II cells (cuboidal cells secreting surfactant fluid)
-many macrophages that digest debris & bacteria
-surrounded by elastic fibers
-have alveolar pores

Openings between adjacent alveoli
-allow equalization of inflation

Mostly air-filled spaces and elastic CT

Right and left lungs are suspended in their own subcavities within thoracic cavity

Just deep to clavicle

Just superior to diaphram

Indentation on mediastinal aspect of each lung
-site entry of main bronchus to each lung
-also entry of pulmonary blood vessels and systemic blood vessels

The left lung has 2 lobes and the right lungs have 3 lobes. Lobes are separated by fissures.

Pulmonary & Bronchial

Gas exchange. Carbon dioxide from blood to lung air and oxygen from lung to blood.

Sympathetic & parasympathetic fibers
-enter at hilum and run along bronchial tree with blood vessels

Cause smooth muscle constriction of bronchiole tubes

Release neurotransmitters that cause bronchiole smooth muscle relaxation and dilation of tubes

Thin, double-layer of serous membranes

Lines inside of thoracic cavity and superior diaphram

Space between parietal & visceral pleurae, filled with pleural fluid (lubricating)

Lines the outer surface of lungs

Atmospheric Pressure = 760 mmHg (at sea level)
Pulmonary Pressure/Alveolar Pressure = Atomspheric Pressure (after equilibration)
Intrapleural Pressure = about 3-4 mmHg less than Atmospheric Pressure

Negative pressure always less than atmospheric pressure and is needed to keep lungs from collapsing.

Volume changes for breathing. Diaphragm contracts and flattens inferiorly. External intercostals contract to expand rib cage. Internal intercostals contract to contract rib cage for forced exhalation.

Elasticity of lung tissue allow passive exhalation:
1. elastic fibers around alveoli
2. surface tension of fluid lining inside of alveolar walls

Amphiphilic/amphipathic, detergent like molecule
-secreted by Type II alveolar cells
-decreases surface tension of fluid
-saves from having to reinflate alveoli

Inhaling it

About 500 mL, during quiet breathing

About 3100 mL, amount of air that can be inhaled after normal inhale

About 1200 mL, amount of air that can be exhaled after normal exhale

About 1200 mL, volume of air that cannot be exhaled

Instrument for measuring lung volumes and capacities

increased airway resistance

Reduction in lung capacity

Deep breath, then forcefully exhale as quickly as possible

Amount of air expelled within a particular time interval of FVC test

Some inspired air only gets into conducting zone, not reach respiratory zone, so not participate in gas exchange

Volume of conducting zone (about 150mL)

Volume from alveoli that do not have gas exchange

=(TV)(breaths per minute)

=(TV - DeadSpace)(breaths per minute)

Measure of ease with which lungs expand

Blood in capillaries exchanges gases with air in alveoli

About 98% of oxygen pick up in lungs is transported by hemoglobin in red blood cells.

Unloading of oxygen from Hb to tissues influenced by tissue pressure of oxygen

Ventral Respiratory Group (VRG) & Dorsal Respiratory Group (DRG)

Network of neurons in ventral brainstem that extends from pons-medulla to spinal cord and seems to be the rhythm-generating center

Impulses travel along phrenic nerve & intercostal nerves

Inspiratory outputs stops

Neurons intergrate input from peripheral stretch receptors and chemoreceptors, relays info to influence VRG activity

Any disorder in which there is long-term obstructive of airflow and substantial reduction of pulmonary ventilation.

Most common chronic illness in children (around 5000 deaths per year of all ages and rising)

Allergen exposure, release of imflammatory chemicals from mast cells

Triggered by things such as infections, pollutants, cold air, excercise, emotions

Bronchiole spasms, mucus buildup, severe coughing, wheezing, sometime suffocation, and later on tissue damage

-Destruction of alveolar walls -> larger, but fewer alveoli
-Lungs lose elasticity -> become over-compliant
-Inspiration OK; expiration requires much work
-Air passages tend to collapse & trap air
-Highly inflated lungs -> barrel-chested -> stretched inspiratory muscles