QUIZ #2 STUDY GUIDE (CHAPTER #22) – Flashcards

1. Pulmonary ventilation (commonly called breathing): Air is moved into and out of the lungs (during inspiration and expiration) so the gases there are continuously changed and refreshed. 2. External respiration: Oxygen diffuses from the lungs to the blood, and carbon dioxide diffuses from the blood to the lungs. 3. Transport of respiratory gases: Oxygen is transported from the lungs to the tissue cells of the body, and carbon dioxide is transported from the tissue cells to the lungs. The cardiovascular system accomplishes this transport using blood as the transporting fluid. 4. Internal respiration: Oxygen diffuses from blood to tissue cells, and carbon dioxide diffuses from tissue cells to blood.

The nose moistens and warms the air. The hairs and mucous help to clean & filter the air. The nasal conchae protrude from the lateral walls. They increase the mucosal area. Enhance air turbulence. During exhalation the nasal cavity reclaim heat and moisture.

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Speech involves intermittent release of erpiredar and the opening and closing of the glottis. The length of the true vocal cords and the size of the glottis change with the action of the intronoic laryngeal mucus that clone the cartilages ?????

The trachea's elastic elements make it flexible enough to stretch and move inferiorly during inspiration and recoil during expiration, but the cartilage rings prevent it from collapsing and keep the airway patent despite the pressure changes that occur during breathing. The open posterior parts of the cartilage rings, which abut the esophagus, are connected by smooth muscle fibers of the trachealis and by soft connective tissue. Because this portion of the tracheal wall is flexible, the esophagus can expand anteriorly as swallowed food passes through it. Contraction of the trachealis muscle decreases the trachea's diameter, causing expired air to rush upward from the lungs with greater force. This action helps expel mucus from the trachea when we cough by accelerating the exhaled air to speeds of 100 mph! The last tracheal cartilage is called the carina. marking the point where the trachea branches into the two main bronchi. There is the submucosa which is the middle stratum of the trachea. This is a layer of dense connective tissue in which the tracheal glands are embedded. There are also blood vessels, nevers, and lymphatics here. The glands are mixed glands of tubuloalveolar type and they mainly contain mucous cells. There are demilunes of serous cells that cap the mucous cells. The ducts from these glands go through the lamina propria to empty onto the epithelial surface. Decrease in the flow of air through the upper airway for 10 seconds, decreasing O2 saturation or abrupt arousal from sleep

LUNGS: -Apex: superior tip. -Base: Inferior surface that rests on the diaphragm. -Hilum: On mediastinal surface, site of attachment of blood vessels, bronchi, lymphatic vessels, and nerves. -Cardiac notch of left lung: concavity that accommodates the heart. *Left lung smaller, has 2 lobes (superior and inferior) *Right lung has 3 lobes (superior, middle, inferior lobes) ALVEOLI: Surrounded by fine elastic fibers. Contain open pores that - 1. connect adjacent alveoli, 2. allow air pressure throghout the lung to be equalized. House alveolar machrophage that keep alveolar surfaces sterile.

VENTILATION: Involves inspiration (movement of the air into the lungs) and expiration (movement of the air out of the lungs). Depend on volume changes in thoracic cavity. Volume change -> pressure changes-> Pressure changes -> gases flow to equalize pressure. PERFUSION: The process of forcing blood or other fluid to flow through a vessel and into the vascular bed of a tissue to provide oxygen & other nutrients.

???? Quiet inspiration mechanics (Diaphragm, external intercostal muscles) and Quiet expiration, Deep inspiration and expiration: Involves other muscles, pulmonary ventilation, getting air in and out of body, dependent on changes of space in chest cavity - inspiration - ribs up, diaphragm down, abdominal muscles down and out, negative pressure forces air in, expiration - lungs recoil, diaphragm rises, pushing air out and reestablishing pressure Negative pressure Pip is caused by opposing forces. Two inwards forces promote lung collapse: 1. Elastic recoil of lungs decreases lung size (wants to collapse) 2. Surface tension of alveolar fluid reduces alveolar size One outward force tends to enlarge the lungs 1. Elasticity of the chest wall pulls the thorax outward. Creates pressure to keep chest open.

Boyle's Law states that when the pressure rises, the volume decreases and when the pressure decreases the volume increase. P1V1=P2V2 Relationship between pressure and volume of a gas. Pressure (P) varies INVERSELY with volume (V)

Inspiratory muscles consume energy to overcome 3 factors that hinder air passage and pulmonary ventilation. 1. Airway resistance. ??? 2. Alveolar surface tension. ??? 3. Lung compliance. Diminished by scar tissue/fibrosis, reduced production of surfactant, decreased flexibility of thoracic cage.

TYPE I ALVEOLAR CELLS: Flattened squamous epithelial cells that allow passage of gas across their cytoplasm. Terminally differentiated. Cover majority of alveolar wall TYPE II ALVEOLAR CELLS: Scattered throughout lungs. Cuboidal cells secrete surfactant & anitmicrobial proteins.

Spirometer: instrument used to measure respiratory volumes and capacities. Spirometer can distinguish btw: - Ostructive Pulmonary disease - increased airway resistance (bronchitis) - Restrictive diorders - reduction in total lung capacity due to structural/functional changes (fibrosis/TB). - Minute ventilation: total amount of gas flow into or out of the resp. tract on 1 minute. PFT: 1.Increases in TLC, FRC, and RV may occur as a result of obstructive disease. 2. Reduction in VC, TLC, FRC, and RV result from restrictive disease.

Forced vital capacity (FVC) - gas forcibly expelled after taking a deep breath. Forced expiratory volume (FEV) - amount of gas expelled during specific time intervals on FVC. Increases in TLC, FRC, and RV may occur as a result of an obstructive disease (long breath) Reduction in VC, TLC, FRC, and RV result from restrictive disease (short breath)

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The total pressure in a mixture of gases is equal to the sum of the partial pressures of all the gases in the mixture

-When a mixture of gases is in contact with a liquid, each gas will dissolve in the liquid in proportion to its partial pressure. -The amount of gas that will dissolve in a liquid also depends upon its solubility. (CO2 is 20x more soluble in water than O2/very little N2 dissolves in water)

Alveoli contain more CO2 and water vapor than atmospheric air; due to - gas exchanges in the lungs - humidification of air - mixing of alveolar gas that occurs with each breath

Partial pressure gradients and gas solubilities. Ventilation - Perfusion coupling Structural characteristics of the respiratory membrane

1) ventilation: amount of gas reaching the alveoli 2) Perfusion: blood flow reaching the alveoli. ** Must be matched or COUPLED for efficient gas exchange - Changes in Po2 in the alveoli cause changes in the diameter of the arterioles. Where alveolar O2 is high, arterioles dilate. Where alveolar O2 is low, arterioles constrict. -Changes in Pco2 in teh alveoli cause changes in teh diameter of the bronchioles. Where alveolar CO2 is high, bronchioles dilate. Where alveolar CO2 is low, bronchioles constrict.

EXTERNAL RESPIRATION: Exchange of O2 and CO2 across the respiratory membrane by diffusion. INFLUENCED BY: -Partial pressure gradients and gas solubilities -Ventilation-perfusion coupling -Structural characteristics of the resp. membrane. INTERNAL RESPIRATION: Capillary gas exchange in body tissues. Partial pressures & diffusion gradients are reversed compared to external respiration. Po2 in tissue is always lower than in systemic arterial blood Po2 of venous blood is 40mm hg & PCO2 is 45 mm hg

O2 carried from alveoli throughout the body by blood. Hgb picks up O2 at the lungs and releases it at the cells. It is 1.5% dissolved in plasma and 98.5% loosely bound to each Fe of Hgb in RBCs (4 O2/hgb) ???

PO2 Temperature Blood pH PCO2 Concentration of BPG

hemoglobin's oxygen binding affinity is inversely related to both acidity and concentraion of carbon dioxide. Aka decrease in blood pH or an increase in blood CO2 results in hemoglobin releasing their loads of Oxygen, while the reverse makes them pick up oxygen As cells metabolize glucose: -PCO2 and H+ increase in concentration in capillary blood. Declining pH weakens the Hbg-O2 bond (Bohr effect) -Heat production increases Increasing temp directly and indirectly decreases Hgb affinity for O2.

Inadequate O2 delivery to tissues due to: Too few RBC's Abnormal or too little Hgb Blocked circulation Metabolic poisons Pulmonary disease Carbon Monoxide

In 3 forms: 1) Dissolved in blood plasma- 7-10% 2) Bound to globin of Hgb (carbaminohemoglobin)- 20% 3) Bicarbonate ion dissolvedin plasma- 70%

CO2 combines w/ water to form carbonic acid (H2CO3) which quickly dissociates. CO2 + H2O H2CO3 (HCO3)- + H+ Most of the above formula occurs in the RBC's. In systemic capillaries - HCO3 quickly diffuses from RBC's into the plasma. The chloride shift occurs: outrush of HCO3 from RBC's is balanced as CL moves in from the plasma. In pulmonary capillaries: HCO3 moves into RBC's & binds w/ H+ to form H2CO3. H2CO3 is split by carbonic anhydrase into CO2 and water. CO2 diffuses into alveoli. CO2 + H2O H2CO3 (HCO3)- + H+ H2CO3 is carbonic acid HCO3 is bicarbonic ion

HCO3 in plasma is the "alkaline reserve" of the carbonic acid bicarbobate buffer system. If H+ concentration in blood rises, excess H+ is removed by combining with HCO3. If H+ concentrations begin to drop H2CO3 disassociates releasing H+.

The effect of oxygen on carbon dioxide binding to hemoglobin. When oxygen binds to hemoglobin, it decreases the affinity of hemoglobin for carbon dioxide so it causes more carbon dioxide to be released., Bohr Effect - increases O2 delivery (to tissue) by decreasing Hb affinity for O2 (via increased CO2 and H+ in peripheral sites) Haldane effect - increase CO2 delivery (to lung) by decreasing Hb affinity for H+ and CO2 (via increased PO2 in lung)

Medulla = 1. Dorsal Respiratory group (DRG) Near the root of cranial nerve IX Integrates input from peripheral stretch & chemoreceptors. 2. Ventral Respiratory group (VRG) Rhythm generating & integrative center Sets eupenia (12-15 breath/ min) Inspiratory neurons excite insp muscles via phrenic & intercostal nerves Expiratory neurons inhibit the inspiratory neurons

Depth is determined by how actively the resp center stimulates the resp muscles. Rate is determined by how long the inspiratory center is active. Both are modified in response to changin body demands. ????

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Stretch receptors in the pleura and airways are stimulated by lung inflation. Inhibitory signals to the medullary respiratory centers & inhalation & allow expiration to occur. Acts more as a protective repsonse than a normal mechanism.

Adjustments are made for the intensity and duration of exercise. Hyperpnea = increase in ventilation (10-20 fold) in response to metabolic needs. Pco2, Po2, and ph remain surprisingly constant during exercise. Pyschological stimuli - anticipation of exercise Simultaneous corticol motor activation of skeletal muscles & Resp centers. Exitatory impulses reaching resp centers from medulla.

HYPERCAPNIA: Abnormally high level of carbon dioxide in the body and tissues. HYPERVENTILATION: HYPERNEA: Increase in ventilation (10 to 20 fold) in response to metabolic needs.

HYPOCAPNIA: not enough CO2 in the blood HYPOVENTILATION: Decreased respiration= inadequate alveolar ventilation in relation to metabolic demands. Can cause respiratory acidosis and hypercapnia. HYPOPNEA: Decrease in the flow of air through the upper airway for 10 seconds, decreasing O2 saturation or abrupt arousal from sleep

Chemorecepters become more responsive to Pco2 when Po2 declines. Sustantial decline in Po2 directly stimulates peripheral receptors. Decline in O2 stimulates the kidneys to accelerate production of EPO. RBC count slowly goes up.

Chronic obstructive pulmonary disease (COPD) is one of the most common lung diseases. It makes it difficult to breathe. Smoking is the leading cause of COPD. Irreversible. Decreases the amout of air one can exhale. Chronic bronchitis/ emphysema. ???

"Pink Puffer" Barrel Shaped Chest Enlargement of air spaces and decreased recoil resulting from destruction of alveolar walls, increased compliance. Increased elastase activity, increased lung compliance due to loss of elastic fibers. Exhale through pursed lips to increase airway pressure and prevent airway collapse during exhalation.

Arises with reactivation of Mycobacterium tuberculosis Occurs at apex of lung (high oxygen tension) Forms cavitary foci of caseous necrosis May lead to miliary pulmonary TB or TB bronchopneumonia

an abnormal respiratory condition associated with allergic hypersensitivity to certain inhaled allergens, characterized by bronchospasm, wheezing, and dyspnea. Airway inflammation due to an immune response caused by release of interleukins.

A pneumonia that occurs from abnormal entry of secretions or substances into the lower airway. It usually follows aspiration of material from the mouth or stomach into the trachea and subsequently the lungs.

1. Squamous cell carcinoma = in bronchial epithelium 2. Adenocarcinoma = peripheral lung areas 3. Small cell carcinoma = Has lymphocyte type cells that originate in the primary bronchi and metz

At birth, Resp centers are activated, alveoli inflate and lungs begin to function. Resp rate is high in newborns & slows into adulthood.

Thorax becomes rigid, lungs lose elasticity, vital capacity declines, respiratory system protective mechanisms lose efficiency, blood O2 levels decline & elderly become hypoxic during sleep which causes sleep apnea