Module 2 Flashcards
Gross anatomy
the study of the organs and structures of the human body visible to the naked eye
Lung Shape
The lungs are not symmetrical. This asymmetry is due the position of the heart, which is situated slightly to the left of the median plane
Right Lung Lobes
The right lung has three lobes: superior, middle, and inferior. It had oblique fissures separating the lobes. The right lung also has a horizontal fissure separating the superior and middle lobes.
Left Lung lobes
The left has two lobes: superior and inferior. It has oblique fissures separating the lobes
hilum
The “root” of the lung. This is where the pulmonary vessels and bronchi enter each lung
pleurae
membranes that cover the surface of the lung and the cavity surrounding the lungs. The pleurae reduce friction and provide a negative pressure environment needed for lung inflation. The pleurae also help to pull the lungs open with the chest wall during inhalation.
visceral pleura
directly covers the lungs
parietal pleura
covers the surfaces surrounding the lungs: the rib cage, diaphragm, and mediastinum.
pleural space or cavity
The space that is formed between the pleurae
3 main functions of respiratory system
1) air conduction, 2) air filtration, and 3) exchange of gases
respiration
the exchange of gases
6 Conducting portions of the lungs
i. Nostril - nasal cavities
ii. Pharynx: nasopharynx, oropharynx, laryngopharynx
iii. Larynx
iv. Trachea
v. Paired main (primary) bronchi (bronchi is the plural form of bronchus)
vi. Bronchioles: secondary and tertiary
3 parts of the pharynx
nasopharynx, oropharynx, laryngopharynx
2 types of Bronchioles
secondary and tertiary
3 Filtration portions of lungs
i. Nostrils: hairs, cilia, and mucus producing goblet cells
ii. Trachea and bronchi: cilia and mucus producing goblet cells
Nostrils have
hairs, cilia, and mucus producing goblet cells
Trachea and bronchi have
cilia and mucus producing goblet cells
4 Respiratory portions of lungs
i. Respiratory bronchioles
ii. Alveolar ducts
iii. Alveolar sacs
iv. Alveoli
The human respiratory system
includes all structures that conduct air to and from the lungs
nasal cavities or fossae
composed of bone and cartilage, The left and right fossae are separated by the nasal septum
vestibule
most external portion of the nasal cavity just inside the nostrils covered by stratified squamous epithelium (continuation of the outside skin)
vibrissae
Short thick hairs act as a screening device for the respiratory tract
nasal conchae
folds found past the vestibule, increasing the surface area so that the incoming air can be warmed and humidified
Why do nose bleeds commonly occur?
because the nasal cavity is highly vascularized (has a large number of blood vessels) in order to warm the air.
3 regions of pharynx
nasopharynx
oropharynx
laryngopharynx
nasopharynx
the connection area between the nasal cavity and pharynx, generally above the soft palate
Eustachian tubes
connect the nasopharynx to each middle ear.
oropharynx
caudal to the mouth and anterior to the epiglottis
laryngopharynx
the area where the pharynx, larynx, and esophagus meet. It is superior and posterior to the larynx
hard palate
separate the nasal cavities from the mouth
soft palate
separate the nasal cavities from the mouth
aspiration
when food or liquid accidentally enters the trachea. This can happen because the air and food passages cross in the pharynx
3 Benefits of a shared pharynx passage
This lets air enter through the mouth in case the nasal cavity is obstructed (such as nasal congestion).
The shared passage also allows for relatively normal breathing during eating.
This relationship permits greater intake of air during heavy exercise, when greater gas exchange is required.
glottis
is an opening into the larynx, or voice box
Vocal cords
vocal folds (“true vocal cords”). Flexible and pliable bands of connective tissue vibrate and produce sound when air is expelled past them through the glottis from the larynx. They are at the edges of the glottis, embedded in mucous membranes
larynx
Attached to the trachea. The larynx and the trachea are permanently held open to receive air. The larynx is made up of single cartilages and paired cartilages.
3 single cartilages
epiglottis
cricoid cartilage
thyroid cartilage
epiglottis
guards the superior opening of the larynx
thyroid cartilage
called the “Adam’s apple” and is larger in males
3 Paired cartilages
arytenoid cartilage
corniculate cartilage
cuneiform cartilages
These are smaller than the single cartilages
trachea
is held open by a series of C-shaped, cartilaginous rings that do not completely meet on the posterior side of the trachea
trachealis (smooth) muscle
Posterior part of trachea. The “open” region of the trachea is bridged by this and a ligament
expectorated
spit up
pneumonia
Infection of the lungs. Aspiration can cause this if there is a large amount of food or liquid that is aspirated and travels to the lungs.
3 Steps of the swallowing process
1) The larynx rises, and the trachea is closed by a flap of tissue called the epiglottis.The epiglottis moves inferiorly to cover the trachea to prevent food or liquid from entering the lungs.
2) A posterior and superior movement of the soft palate covers the entrance of the nasal passages. The upward movement of the soft palate prevents food or liquid from entering the nasal passages during the swallowing process.
3) The food then enters the esophagus, which lies posterior to the larynx and trachea.
Main bronchi
2 main bronchi that enter the right and left lungs; each then branches into a great number of smaller passages called bronchioles. The two main bronchi resemble the trachea in structure, but as the bronchial tubes divide and subdivide, their walls become thinner, and rings of cartilage are no longer present.
Bronchi
Represent the transition from the single conduction pathway of the upper airways into the large surface area required for gas exchange.
bronchioles
When the main bronchi branch into a great number of smaller passages
Respiratory epithelium
lines the entire bronchial tree
Two main bronchi
The trachea bifurcates into two main stem bronchi:
(primary) bronchi, (secondary) lobar bronchi.
Secondary bronchi
branch into the lungs. 3 into the right lung and 2 into the left lung. The main bronchi look like the trachea, but as they branch and become smaller the cartilaginous content decreases.
Tertiary bronchi
as the bronchi continue to subdivide, until reaching 1 mm in diameter.
Bronchioles
When the tertiary bronchi reach 1 mm in diameter, they form the interface between the conducting portion and respiratory portions of the respiratory system. Bronchioles terminate in alveoli, which are surrounded by capillary beds to enable the exchange of carbon dioxide and oxygen within the lungs.
2 types of bronchioles
Terminal bronchioles
Respiratory bronchioles
Terminal bronchioles
the smallest air conducting bronchioles
Respiratory bronchioles
the transitional zone in the respiratory system concerned with both air conduction and gas exchange.
alveoli
Within the alveolar sacs elongated space enclosed by a multitude of tiny air pockets. Where the respiratory bronchiole terminates. There are millions of alveoli inside the lungs to enable the exchange of gases. Alveoli represent the site of gas exchange as well as the blood-air barrier
Alveolar ventilation
movement of air into and out of the alveoli
Alveolar sacs
grape-like clusters of alveoli
concentration gradient
Oxygen diffusing into the blood from each lung and CO2 diffusing out of the blood into the lungs is based on the concentration gradient of each gas. Gases also follow their concentration gradient, moving from a higher to lower concentration. This generally results in O2 moving into the blood and CO2 moving out of the blood.
goblet cells
produces mucus and helps trap debris before going into the lungs-shaped like a wine glass
2 types of nasal cavities
vestibule
nasal septum
Histology
the study of the cellular anatomy of a tissue or organ that can be viewed through a microscope
respiratory epithelium
(or lining of the respiratory tract) is primarily made of ciliated, pseudostratified, columnar cells
cilia
small hair-like projections
apical side
at the apex or top of the cells
pseudostratified
they appear to be in layers
basement membrane
or “floor” of the epithelial tissue
columnar cells
cells that are are taller than they are wide
stratified squamous epithelium
Stratified means layered and squamous means flattened so it is found in multiple flattened layers found in vestibule right inside nostril
Simple squamous
refers to a single layer of flattened cells found in smaller bronchioles
The primary function of the cells within the alveoli
to allow efficient exchange of gases between the air and blood
surfactant
A lipoprotein, covers the luminal surface and keeps the alveoli from sticking together during exhalation
Without surfactant the open, circular structure of the alveoli cannot maintain their shape, making the exchange of gases difficult or impossible. The lungs of premature babies often have not developed the ability to make surfactant. This is the reason many preemies have respiratory problems after birth and need to remain hospitalized until their lungs fully develop.
alveolar macrophages
type of cell found within the alveoli also known as dust cells. The most abundant cell within the alveoli. They phagocytize toxic particles, allergens, or infectious material. They are the primary immune defense system of the alveoli. Once a macrophage has phagocytized a particle or pathogen, it migrates toward the ciliary surface of the bronchiolar system. Once on the surface, the cilia carry the macrophage and particles to the mouth to be expectorated or swallowed.
4 Steps of Respiration
- Breathing
- External respiration
- Internal respiration
- Aerobic cellular respiration
Breathing
includes inspiration (breathing air in) and expiration (breathing air out)
External respiration
gas exchange with the environment at a respiratory surface
Internal respiration
gas exchange between blood and tissue fluid
Aerobic cellular respiration
production of ATP (adenosine triphosphate) in cells
3 things for diffusion to be effective in the gas-exchange region
(1) moist
(2) thin
(3) large in relation to the size of the body.
hemoglobin
an oxygen carrying molecule
Ventilation
happens as the lungs move air into the respiratory tract (inhalation) and out of the respiratory tract (exhalation). A negative pressure environment is created inside the lungs by the pleural space, which means that the pressure inside this space is less than that of the atmosphere.
inhalation
the rib cage lifts superiorly and anteriorly to open up and expand the lungs. The diaphragm is flattened as it contracts, pulling the lungs open. As the thoracic cavity expands and lung volume increases, the density of the gases filling the lungs decreases. Because air pressure outside of the lungs is now greater than inside (where there is negative pressure), air will naturally flow into the lungs.
exhalation
the rib cage is lowered, the diaphragm rises, the thoracic pressure increases, and air will naturally move out of the lungs where the pressure is lower. The lungs do not completely empty during each breathing cycle
lungs do not completely empty during each breathing cycle this is called:
incomplete ventilation
this primarily accounts for the exchange of gases between the air in the alveoli and the blood in the pulmonary capillaries:
diffusion
Hemoglobin
helps to assist natural diffusion. Most oxygen entering the blood combines with hemoglobin (found in red blood cells)
oxyhemoglobin
when oxygen entering the blood combines with hemoglobin
carbaminohemoglobin
when hemoglobin combines with carbon dioxide
bicarbonate ion
created when Carbonic anhydrase combines with carbon dioxide and water
an enzyme in red blood cells
Carbonic anhydrase
atmospheric pressure at sea level
= 760 mm Hg (mercury) = 1 atm (one Atmosphere)
Boyle’s Law
The pressure of a given quantity of gas is inversely proportional to its volume. This means that there is higher pressure in a smaller volume or less pressure in a greater volume. Boyle’s law is a relationship between gas and pressure. This helps explain why inspiration and expiration can take place.
Charles’s Law
The volume of a given quantity of gas is directly proportional to its temperature. Charles’s law helps explain why warming air is beneficial to the respiratory system. The higher the temperature the greater gas volume, or the lower temperature the lower gas volume.
Dalton’s Law
The total pressure of a gas mixture is equal to the sum of the partial pressures (pp) of the individual gases. (i.e. ppO2 + ppCO2 + ppN2 = 1 atmosphere). There are different gas quantities or partial pressures in the body. The concentrations and partial pressures of gasses will affect the diffusion of those gases.
spirometer measures these 4 things:
Tidal Volume (TV)
Inspiratory Reserve Volume (IRV)
Expiratory Reserve Volume (ERV)
Residual Volume (RV)
Vital Capacity (VC) =
ERV+TV+IRV
Total Lung Capacity (TLC) =
VC +RV
Inspiratory Capacity (IC) =
TV+IRV (or) VC-ERV
Functional Residual Capacity (FRC) =
RV+ERV
RR
respiratory rate, (typically measured in breaths per minute)
Emphysema
causes damage to the alveoli.
Eventually, the damage causes the inner walls of the alveoli to become weak and rupture.
The loss of alveoli causes a loss of alveolar ventilation ability and a loss of total gas exchange.
Breathing becomes very difficult for these patients even at rest.
Smoking is often a cause of this disease.
Cystic fibrosis
hereditary disease.
Cystic fibrosis impacts cells throughout the body, but the most notable impact is within the epithelial cells of the respiratory tract.
The cells produce mucus without enough saline.
This causes mucous to become too thick so it clogs the respiratory tract. Chronic respiratory infections eventually lead to respiratory failure.
Cystic fibrosis patients have a shortened life expectancy because of these medical complications.
Pulmonary edema
is an accumulation of fluid in the lungs.
caused by several diseases, such as infections, cancers, and congestive heart diseases.
When a doctor listens to the lungs (auscultates) of a patient with pulmonary edema, the fluid makes crackle sounds. This sound happens as the fluid-filled alveoli “pop” open with each breath.
Pleurisy
or pleuritis is inflammation of the pleura (lining of the lungs) due to infection, cancer, or injury.
In this condition, the pleural space fills up with air, pus, blood, or other fluids.
Pleuritis causes sharp chest pain that worsens with breathing. The layers of the pleural cavity rub against each other creating friction.
The increased fluid in the pleural cavity can make it difficult for a doctor to even hear a person’s heart sounds when auscultating their chest.
auscultates
When a doctor listens to the lungs
pathology
studying, classifying and describing a disease
