respiratory study guide

chapter 22

What two systems work together to deliver oxygen to the tissues and remove carbon dioxide?

The respiratory system and cardiovascular system (circulatory)

Describe how respiration can have different meanings.

External respiration is the exchange of gases between the air and blood. Internal respiration is the exchange between blood and tissue fluid

Describe the major functions of the respiratory system.

Provides O2 and CO2 exchange between the blood and air, serves for speech, provides sense of smell, affects pH of body’s fluids by eliminating CO2, breathing promotes the flow of lymph and venous blood.

What is the difference between the conducting division and the respiratory division? Name the structures that are a part of each.

Conducting division is the passages that serve only for airflow; no gas exchange this includes the nose, pharynx, larynx, trachea, bronchi, bronchioles. Respiratory division consists of the alveoli and other gas exchanging regions

What structures of the respiratory system are in the upper respiratory tract?

Upper respiratory tract is the head and neck; nose through larynx.

What structures are in the lower respiratory tract?

Lower respiratory tract is organs of the thorax; trachea through the lungs.

what is the function of the nose

warms and cleanses and humifies inhaled air.

what is the description of the nares

anterior opening

what is the description of the nasal septum

divides the nasal chambers into 2 (vomer, and perpendicular plate).

what is the description of the vestibule

beginning of the nasal cavity; small dilated chamber inside nostrils.

what is the description of the nasal cavity

posteriorly expands into a larger chamber with not much open space.

what is the description of the paranasal sinuses

frontal, sphenoidal, maxillary, ethmoidal all aid in resonation and warming of air.

what is the description of the conchae

curved bony structures inside the nasal cavity that warm the air, humidify the air, filter and clean the air, and direct airflow of the air your breath in.

what is the description of the respiratory epithelium

has goblet cells that secrete mucous, cilia that propels mucous towards the pharynx.

What is the pharynx, and what are the three different regions of the pharynx? What flows through each region?

Pharynx is a muscular funnel that is a common pathway for respiratory and digestive system. 1^st is the nasopharynx, 2^nd is the oropharynx, and 3^rd is the laryngopharynx.

What is the larynx, and what are its functions? Which is the primary function?

It is the voice box, cartilaginous chamber, connects pharynx to the trachea, primary function is to keep food and drink out of the airway, production of sound.

What is the epiglottis, and what does it do?

Flap of tissue that guards the glottis (opening to the larynx), when swallowing the epiglottis is pushed down to close the airway so food and water do not enter.

Of the nine laryngeal cartilages, which ones are solitary? Which cartilage makes up the Adam’s apple?

Thyroid, cricoid, and epiglottic cartilage. The thyroid cartilage makes up the Adams apple

Which paired cartilages attach to the vocal cords? Which paired cartilages move the vocal cords?

Paired arytenoid cartilages attach to the vocal cords (vocal folds) they also move the vocal cords

What is the purpose of the superior vestibular folds

no role in speech; close the larynx when swallowing

What is the purpose of the inferior vocal cords?

produces sound when air passes between them; contain vocal ligaments (true vocal cords)

Explain in general how sound is produced in the vocal cords.

Intrinsic muscles pull on the corniculate and arytenoid cartilages. Air forced between adducted vocal cords vibrates them

Describe the anatomy of the trachea

Rigid anterior tube anterior to the esophagus. 16-20 c shaped rings of hyaline cartilage.

What type of tissue lines the trachea and why?

Ciliated pseudostratified columnar epithelium, acts as a mucociliary escalator.

Describe the structural differences between the left and right lung.

The right lung is shorter than left because of liver, has 3 lobes: superior, middle, and inferior. The left lung is taller and narrower because of the heart, only has 2 lobes: superior and middle

Describe the flow of air from the primary bronchi to the alveoli.

Primary bronchi —> secondary bronchi —> tertiary bronchi —> bronchioles —> terminal bronchioles —> respiratory bronchioles —> alveolar ducts —> alveolar sacs —> alveoli

Why are the respiratory bronchioles considered to be the beginning of the respiratory division?

Because they participate in gas exchange

How does the tissue change as the tree branches?

It starts with cartilage from the trachea, then it lessons and smooth muscle takes over; columnar cells change to cuboidal

what is the function of simple squamous alveolar cells (type 1)

gas diffusion between alveolus and bloodstream.

what is the function of great alveolar cells (type II)

cuboidal cells that repair when the squamous cells are damaged, secrete pulmonary surfactant.

what is the function of alveolar macrophages (dust cells)

keep alveoli from debris by phagocytizing dust particles.

Explain the components of the respiratory membrane. Why must it be thin and have surfactants?

Squamous alveolar cells and endothelial cells of blood capillary, they are shared by basement membrane. It must be thin for gas exchange.

What is the visceral layer of the pleurae?

serous membrane that covers the lungs

what is the parietal layer of the pleura?

adheres to the mediastinum, inner surface of the rib cage and superior surface of the diaphragm.

what is the pleural cavity?

potential space between the pleurae (Film slippery of pleural fluid)

Why do we have a pleurae?

Pleurae reduce friction and conduct compartmentalization

define inspiration

inhaling

define expiration

exhaling

define respiratory cycle

Respiratory cycle is a full cycle of inhaling and exhaling

What are the major respiratory muscles?

diaphragm, internal, external intercostals.

What happens during quite respiration?

diaphragm and external intercostals contract during inspiration, during expiration muscles relax, structures recoil to original shape and results in airflow out of the lungs.

What happens during forced inspiration ?

the diaphragm and external intercostals contract during inspiration.

What happens during forced expiration?

the internal intercostals and abdominal muscles contract.

What is the Valsalva maneuver?

taking a deep breath, holding it closed by the epiglottis and then contracting the abdominal muscles to raise abdominal pressure and push organ contents out.

Explain how the Ventral respiratory group in the brainstem control respiration

primary generator of the respiratory rhythm (receives info from the dorsal)

Explain how the dorsal respiratory group in the brainstem control respiration

modifies the rate and dept of breathing

Explain how the pontine respiratory group in the brainstem control respiration

sends signals to the medullary respiratory centers, helps smooth the transition between inhalation and exhalation, can also shorten or prolong inspiration.  

What do central chemoreceptors receptors respond to?

changes in pH of cerebrospinal fluid

What do peripheral chemoreceptors respond to?

O2 and CO2 content of pH of blood

What do stretch receptors respond to?

inflation of lungs

What do irritant receptors respond to?

smoke, dust, pollen, chemical fumes, cold air

How can we voluntarily control breathing?

Originates in the motor cortex of the frontal lobe of the cerebrum. Sends impulses bypassing the brainstem

What is atmospheric pressure? Explain how/what changes in pressure occur in the lungs, and how that determines the flow of air.

drives respiration and is the weight of the air above us (earth’s atmosphere). Air flows into the lungs when pressure is lower than the atmospheric pressure, then flows out of the lungs when pressure is higher than atmospheric pressure. The pressure changes are caused by changes in lung volume during breathing

What are three factors that influence airway resistance?

Airway diameter, mucus or obstructions in the airway, and lung volume

Define alveolar ventilation rate (AVR)

air that ventilates alveoli X respiratory rate

Define Tidal Volume

volume of air being inhaled and exhaled in one cycle during quiet breathing

Define Inspiratory reserve volume

air in excess of tidal volume that can be inhaled with maximum effort

Define expiratory reserve volume

air in excess of tidal volume that can be exhaled with maximum effort

Define Residual volume

air remaining in lungs after maximum expiration

Define vital capacity

total amount of air that can be inhaled and exhaled with the maximum effort

Define total lung capacity

maximum amount of air that lungs can contain

Define minute respiratory volume

amount of air inhaled per minute

Explain what partial pressure is

separate contribution of each gas in a mixture

Explain what occurs during alveolar gas exchange. What aspects allow this process to happen?

It is back and forth traffic of O2 and CO2 across the respiratory membrane. Air in the alveolus Is in contact with a film of water that is covering the alveolar epithelium. For oxygen to get into the blood it must dissolve into this water. It passes through the respiratory membrane, separating the air from the blood stream. For carbon dioxide to leave the blood it must pas the other way, gases diffuse down their concentration gradient.

How is oxygen transported in the blood?

transported by hemoglobin. There is 4 protein (globin) portions, each with a heme group. These then bind one O2 to the ferrous ion (fe2+).

How is carbon dioxide transported in the blood?

transported in 3 ways. As Bicarbonate ions in the plasma, bound to a hemoglobin, and dissolved directly in the plasma.

Explain carbon monoxide poisoning.

competes for the O2 binding sites on the hemoglobin molecule.

Explain Carbon dioxide loading and oxygen unloading at systemic tissues. How does carbonic anhydrase play a role in this? How about the chloride shift?

At the systemic tissues, cells are constantly producing CO2 as a waste product of cellular respiration. This causes carbon dioxide loading into the blood and oxygen unloading from the blood to the tissues. Carbonic anhydrase coverts CO2 into bicarbonate for transport, and the chloride shift moves bicarbonate into the plasma while brining chloride into RBCs to maintain electrical balance.

Explain Carbon dioxide unloading and oxygen loading at the alveoli.

At the alveoli, oxygen diffuses into the blood and binds to hemoglobin, while carbon dioxide is converted from bicarbonate back to CO2, diffuses into the alveoli, and is exhaled. The reverse chloride shift allows bicarbonate to reenter RBCs so it can be converted back into CO2 for removal

How can the body adjust gas exchange to meet the demands of active tissue?

During exercise or increased activity, the body breathes faster and deeper, increases heart output, redirects blood flow to active tissues, and promotes oxygen unloading from hemoglobin, allowing tissues to receive more oxygen and remove carbon dioxide more efficiently

Describe how pH, carbon dioxide, and oxygen levels stimulate breathing.

High carbon dioxide levels, low pH, and low oxygen levels stimulate chemoreceptors, which signal the respiratory centers in the brainstem to increase the rate and depth of breathing to maintain proper gas exchange and blood chemistry

Hypoxia

tissue does not receive enough oxygen

Hypoxemic hypoxia

not enough oxygen in the blood

Ischemic hypoxia

inadequate circulation of blood (congestive heart failure)

Anemic hypoxia

inability of the blood to carry adequate oxygen

Histotoxic hypoxia

metabolic poisons such as cyanide prevent tissues from using oxygen

Chronic bronchitis

affects the airways, the bronchi become inflamed and produce excessive mucus, narrows the airways and makes breathing difficult.

Emphysema

walls of the alveoli are damaged and lose their elasticity, reduces the surface area available for gas exchange and traps air in the lungs