ch23 hw

Calculate the alveolar ventilation if the tidal volume is 500 ml., the respiratory rate is 12/minute, and the anatomical dead space is 100 ml.

4800 ml

With a respiratory rate of 12 breaths per minute and a tidal volume of 500mL, what would the minute ventilation be?

6 liters per minute

1. If intrapulmonary pressure was 760 mm Hg, what would you expect the intrapleural pressure to be?

756 mm Hg

5. The altitude of Kabul, Afghanistan, is approximately 6000 feet. What is the approximate alveolar oxygen partial pressure found here?

85 mm Hg

__________ is a lung disease marked by a reduced number of cilia, reduced motility of the remaining cilia, goblet cell hypertrophy and hypersecretion, and thick sputum.

Chronic bronchitis

2. The empirical formula for bicarbonate is ________________.

HCO3-

3. Carbon dioxide goes through a series of reactions resulting in the formation of bicarbonate. Where does this reaction occur?

Systemic capillaries

Which of the following does not influence the rate of gas diffusion across the respiratory membrane?

Temperature of the gases

Complete each sentence with the correct word.

The majority of CO₂ in the blood is carried as bicarbonate ion. The ability of CO₂ to bind to deoxygenated hemoglobin more readily than it binds oxyhemoglobin is referred to as the Haldane effect. The chloride shift is an anion exchange that takes place in red blood cells as a mechanism to transport bicarbonate ion out of the cell. The combination of carbon dioxide and protein known as carbaminohemoglobin is abbreviated HbCO₂. The decrease in the ability of oxygen to bind to hemoglobin when the pH decreases is known as the Bohr effect. The reaction between CO2 and H2O to form H2CO3 is catalyzed by carbonic anhydrase. Less than 10% of CO₂ is transported as dissolved gas.

Fill in the blanks with the appropriate terms regarding the general functions of the respiratory system.

The respiratory tract is a passageway forair between the external environment and the alveoli (air sacs) of the lungs. There are two gases that are exchanged during respiration. Carbon dioxide diffuses from the blood into the alveoli while the other gas, oxygen, diffuses from the alveoli into the blood. Receptors located in the superior regions of the nasal cavity called olfactoryreceptors detect odors as air moves across them. The vocal cords of the larynx (voicebox) vibrate as air moves across them to produce sound. Sounds then resonate in upper respiratory structures.

1. Surfactant is produced by __________.

Type II pneumocytes

6. Under normal conditions, the alveolar oxygen partial pressure is ______________________ than the atmospheric oxygen partial pressure.

always lower

3. Renal retention of bicarbonate _______________ blood pH, acting as a compensatory mechanism for the condition of respiratory ____________________________

increases; acidosis.

3. The unloading of oxygen at the tissues results in the formation of ______________________ . This configuration of hemoglobin _____________________ carbon dioxide.

deoxyhemoglobin; more readily binds to

1. Negative pressure ventilation, demonstrated by iron lungs, allows a person to breathe by producing an intermittent negative pressure that moves across the chest and diaphragm. This specific action would artificially induce the intrapulmonary pressure to _____________ atmospheric pressure, thus resulting in ______________

drop below; inspiration.

What is the name for the membranes which surround the lungs?

pleural

During expiration, the alveolar pressure must be

greater than atmospheric pressure

2. The intrapulmonary pressure is _______________ than the atmospheric pressure during exhalation.

higher

2. Under normal conditions, the partial pressure of carbon dioxide within the tissues is _____________ than the partial pressure of carbon dioxide within the systemic capillaries.

higher

2. At the respiratory membrane, the partial pressure of carbon dioxide in the plasma is _______ than in the _______ of the lungs.

higher; alveoli

7. Within the Tibetan highlander population, genetic variation has been found to determine relative oxygen-hemoglobin saturation levels. Individuals within this population may be homozygous for either the low oxygen saturation gene or the high oxygen saturation gene. Individuals may also be heterozygous, carrying one low and one high oxygen saturation gene. Based on this information, individuals within the population carrying __________________________ alleles are expected to demonstrate a physiological advantage for survival.

homozygous high oxygen saturation population

2. Acute carbon monoxide poisoning would result in ____________________ of the tissues because oxygen ____________________.

hypoxia; is not released from hemoglobin in sufficient amounts at the tissues

8. No genetic differences were found among the Andean population in either oxygen-hemoglobin saturation levels, nor hemoglobin concentrations. However, this group as a whole displayed higher hemoglobin concentration levels than their lower altitude neighbors. The most accurate explanation for this finding is that individuals constantly exposed to lower atmospheric partial pressures for oxygen would have a physiologic response which would

increase the cumulative number of red blood cells

2. If the atmospheric PCO2 exceeded the alveolar PCO2, the pulmonary capillary PCO2 would

increase well above normal range.

4. Hypoventilation results in a/an _________________ in the arterial partial pressure of carbon dioxide, which may result in respiratory ___________________________.

increase; acidosis.

2. When this negative pressure stops being applied, the lungs __________________, and the intrapulmonary pressure __________________

recoil; increases.

1. Carbonic anhydrase is found in the _______________ where it directly catalyzes the formation of ____________________.

red blood cells; carbon dioxide gas into carbonic acid

1. The inspiratory muscles ____________ during normal exhalation resulting in a/an __________________ in the thoracic volume.

relax; decrease

As air moves down through the tracheobronchial tree, the first structure(s) that contain alveoli will be the

respiratory bronchioles.

3. Increased levels of 2,3 BPG occur in response to decreased blood pH levels. With all other variables unchanged, an increased concentration of 2,3 BPG in the blood would

result in a shift of the oxygen-hemoglobin dissociation curve to the right enhancing unloading of oxygen at the tissues.

2. Increased production of surfactant would

result in an increase in the thickness of the respiratory membrane, which would decrease diffusion of respiratory gases.

1. The binding of CO to hemoglobin causes the oxygen-hemoglobin dissociation curve to

shift to the left, indicating that the carboxyhemoglobin is less likely to release bound oxygen.

1. Respiratory gases cross the respiratory membrane by __________.

simple diffusion

1. Oxygen molecules bind ___________________ of the hemoglobin.

specifically to the heme region

Which of the following is the term for the attraction of water molecules to other water molecules, which help you to exhale by making alveoli smaller?

surface tension

1. Carbon dioxide enters the blood at the _____________________ capillaries. Here, some of the carbon dioxide binds to the _____________ region of hemoglobin.

systemic; globin

At the venous ends of the pulmonary capillaries,

the PCO2 is equal in the capillaries and in the alveoli.

At the arterial ends of the pulmonary capillaries,

the PO2 is lower in the capillaries than in the alveoli.

2. Blood pH decreases in response to

the dissociation of carbonic acid into bicarbonate and hydrogen ions.

1. The reason tetrodotoxin causes death so quickly is directly related to

the loss of respiratory muscle function, which disables a person's ability to appropriately adjust thoracic volumes and associated intrapulmonary pressures.

Which of the following muscles increases the volume of the thorax during a normal inhalation? (1) diaphragm (2) external intercostals (3) internal intercostals (4) rectus abdominis

1, 2

Match the muscle with its role in respiration.

1. Internal intercostals: Contract during expiration 2. External intercostals: Contract during inspiration 3. Diaphragm: Contract during inspiration 4. Abdominal muscles: Contract during expiration

Indicate whether each statement is true or false regarding cerebral and limbic system control of respiration.

1. The cerebral cortex is only involved in unconscious control of respiration. False 2. Emotions can affect respiration via the limbic system. true 3. Voluntary hyperventilation results in decreased blood flow to the brain. true 4. Apnea is the absence of breathing, either voluntarily or involuntarily. true

Indicate whether each statement is true or false regarding the structure of the lungs.

1. The left lung has two lobes and right lung has three. true 2. The cardiac notch is located on the hilum. false 3. Each lobe is subdivided into bronchopulmonary segments. true 4. The bronchopulmonary partitions in each lung are separated by connective tissue. true 5. Bronchopulmonary segments are subdivided into lobes. false

The composition of alveolar air differs from atmospheric air. Indicate all of the factors that account for this difference.

Presence of water vapor Additional carbon dioxide due to gas exchange Less oxygen due to gas exchange

Which of the following functions is associated with the nose?

Producing mucus to trap debris from inhaled air

Which of the following could be involved to assist the diaphragm when you inhale normally?

the external intercostals

The highlighted structures are the ___________.

segmental bronchi

Which component of the respiratory system is shared with the digestive system in that it is a passageway for air as well as food?

Pharynx

What type of cells make up about 90% of the alveolar surface?

Type I pneumocytes

3. Insufficient surfactant production would result in

a tendency for the lungs to collapse.

3. A person suffering from hypercapnia compensates by ____________________ ventilation.

increasing

As acidity of the blood increases, how is affinity of hemoglobin for oxygen affected?

Affinity decreases

Indicate whether each statement is true or false regarding pressure and respiration.

1. A decrease in alveolar volume causes a decrease in intra-alveolar pressure. false 2. During inspiration, pleural pressure is lower than intra-alveolar pressure true 3. As lung volume increases during respiration, pleural pressure decreases. true

Indicate whether each statement is true or false regarding the differences between quiet breathing and labored breathing.

1. During quiet, normal breathing, inspiration is passive. false 2. Muscles contract more forcefully during labored breathing than during normal respiration. true 3. During labored expiration, the volume of the thorax decreases passively. false 4. During quiet expiration, the volume of the thorax decreases passively. true

Indicate whether each statement is true or false regarding pressure of gases.

1. Gases move from an area of lower concentration to higher concentration. False 2. Daltons law states that the total pressure of a gas is the sum of pressures of each gas. true 3. If a single gas represents 60% of the total gas, its partial pressure will be 60% of the total pressure. true 4. If the concentration of oxygen in the alveoli is greater than the concentration of oxygen in the blood, oxygen will diffuse out of the blood. false 5. Typically, carbon dioxide concentrations are higher in the blood than in the alveoli, so carbon dioxide diffuses from the blood to the alveoli. true

Match the description with the appropriate term.

1. The tendency for an expanded lung to decrease in size due to elastic fibers: Lung recoil 2. Water molecules being attracted to other water molecules due to their chemistry (oppositely charged ends of the molecules) surface tension 3. Mixture of lipoprotein molecules produced by secretory cells of the alveolar epithelium to prevent alveoli from collapsing: Surfactant

Match the respiratory system structure with its description.

1. Visible structure on the face: External nose 2. Extends from the nares to the choanae: Nasal cavity 3. Common opening for digestive and respiratory systems: Pharynx 4. Located posterior to the choanae and superior to the soft palate: Nasopharynx 5. Extends from the soft palate to the epiglottis: Oropharynx 6. Extends from the tip of the epiglottis to the esophagus: Laryngopharynx 7. Passageway for air; extends from the base of the tongue to the trachea: Larynx 8. Windpipe; membranous tube attached to the larynx: Trachea 9. Large, conical-shaped organs of respiration: Lungs 10. Small, air-filled chambers for where gas exchange takes place: Alveoli

Indicate whether each statement is true or false regarding carbon dioxide exchange.

1. When hemoglobin is saturated with oxygen, it readily takes up carbon dioxide molecules. false 2. In the chloride shift, HCO3- is exchanged for Cl-. true 3. HCO3- joins with H+ to form carbonic acid. true 4. The release of hydrogen ions from hemoglobin results in an uptake of oxygen by hemoglobin. true

Indicate whether each statement is true or false regarding oxygen and carbon dioxide transport in the blood.

1. When your bodys temperature increases, more oxygen is released from hemoglobin. True 2. When carbon dioxide levels increase at the tissue capillaries, blood pH decreases. true 3. An increase in blood carbon dioxide levels results in an increase in hemoglobins affinity for oxygen. false 4. When carbon dioxide leaves the blood at the pulmonary capillaries, pH levels decrease. false

4. Using the graph provided, determine the correct oxygen partial pressure associated with the classification of "high altitude."

112 mm Hg

3. When using positive pressure ventilators, what triggers the elastic recoil of the lung, and what does this action cause?

Airway pressure reaching zero; expiration

2. Which environment separated by the respiratory membrane would display the highest oxygen partial pressure?

Alveolar air

In which of the following sequences does PO2 progressively decrease?

Atmospheric air, blood in aorta, systemic tissues

Carbon dioxide is more soluble in water than is oxygen. Which gas has the higher rate of diffusion?

Carbon dioxide

Select the correct word from the list to complete each sentence.

Carbon dioxide diffuses into red blood cells and plasma in the tissues. Carbon dioxide diffuses out of red blood cells and plasma in the lungs. In the chloride shift, HCO3- is exchanged with Cl- in the red blood cells in order to maintain electrical neutrality. The Haldane effect occurs in the lungs, when hemoglobin that is bound to oxygen is less able to bind with carbon dioxide. In the tissues, hemoglobin releases oxygen. When hemoglobin releases oxygen, it is more able to bind with carbon dioxide.

Which of the following explains why the PO2 of the blood leaving pulmonary capillaries is 104 mm Hg, but the blood leaving the lungs to enter the left atrium is 95 mm Hg?

Deoxygenated blood from bronchial circulation is mixed with blood from oxygenated alveolar circulation.

2. If four new drugs were discovered and each of them resulted in the unique physiologic responses indicated below, which drug do you think would hold the most promise as a cure for tetrodotoxin poisoning?

Drug 3

Which of the following structures is part of the respiratory system? Select all that apply.

Nasal cavity Trachea Pharynx larynx

1. ___________________ is used to sustain metabolic activities within the cells, and ________________ is produced as a result of these activities.

Oxygen; carbon dioxide

Which of the following receptors is stimulated by a decrease in pH caused by metabolic issues (rather than acidosis caused by a change in CO2 levels)?

Peripheral chemoreceptors

When H+ levels in the blood increase, how will respiratory rate and depth be affected?

Respiratory rate and depth will increase.

For air to flow into or out of the lungs, there must be

a pressure gradient established between the atmosphere and the alveoli.

Normally, the partial pressure of oxygen gas is higher in the

air within the alveoli.

1. Hyperpnea would result in ___________________________ within the blood.

an increase in PO2 and a decrease in PCO2

2. Contraction of the diaphragm and external intercostal muscles results in ____________ in the thoracic volume which results in _______________ of the intrapulmonary pressure.

an increase; a decrease

The nasal vestibule is located in the ______ portion of the nasal cavity.

anterior

1. Under normal conditions, the region expected to have the lowest PCO2 is the ___________________.

atmosphere

Hyperventilation _____ plasma carbon dioxide levels, which _____ plasma pH.

decreases; increases

When carbon dioxide levels in the blood increase, the

blood becomes more acidic.

One of the functions of the respiratory system is to alter the levels of carbon dioxide in the blood, thus regulating __________.

blood pH

Most oxygen is carried in the blood ______, but most carbon dioxide is ________.

bound to hemoglobin; associated with bicarbonate ions in the plasma

Oxygenated blood is carried to the tissues of the lungs via the __________.

bronchial arteries

The ranking from highest to lowest PO2 in the area of the arterial ends of the tissue capillaries is

capillaries, tissue fluid, cells.

1. Which of the following are bicarbonate ions exchanged for when they diffuse from plasma back into red blood cells?

chloride ions

The two mechanisms used to prevent food from entering the larynx are

closure of the glottis. tipping of epiglottis over glottis.

During inspiration, the diaphragm _______ and the volume of the thoracic cavity _________, whereas during expiration, the diaphragm _________ and the volume of the thoracic cavity ___________.

contracts; increases; relaxes; decreases

The part of the respiratory system where gas exchange does not take place is called _________.

dead space

Which of the following statements concerning the lungs and the pleura is true?

each lung is suspended

Since the diaphragm is not contracting when you exhale, where does the force come from that makes the thoracic cavity smaller and increases pressure during normal exhalation?

elastic recoil

A lung disease marked by abnormally few but large alveoli is __________.

emphysema

The condition of newborns called infant respiratory distress syndrome is caused by

lack of surfactant.

2. Decreased PCO2 results in an increase in blood pH levels. Both of these conditions result in a shift of the oxygen-hemoglobin dissociation curve to the ______________________. This shift _______________ hemoglobin's affinity for oxygen.

left; increases

The largest division of each lung are _____, which are divided into _____.

lobes; segments

Expiration during quiet breathing

occurs when the diaphragm and external intercostal muscles relax.

2. A single hemoglobin displaying a saturation level of 75% would be bound to __________.

three oxygen molecules

1. Oxygen unloading occurs at the _________________________. This process causes a/an _________________ in the oxygen partial pressure of the blood leaving this region.

tissues; decrease

Gasses diffuse because of differences in partial pressures from areas of higher pressure to areas of lower pressure.

true

When partial pressures for a given gas are equal between the capillaries and the tissue fluids, no net movement of that gas occurs.

true

The lungs have

two blood flow routes and two lymphatic supplies.