respiratory

Match each respiratory capacity with its approximate value. - total lung capacity (TLC): - inspiratory capacity (IC): - vital capacity (VC): - functional residual capacity (FRC):

- TLC: about 5800mL - IC: about 3500mL - VC: about 4600mL - FRC: about 2300mL

Match each pulmonary volume with its approximate value. - tidal volume (TV): - inspiratory reserve volume (IRV): - expiratory reserve volume (ERV):

- TV: about 500mL - IRV: about 3000mL - ERV: about 1100mL

Match each pulmonary volume with its definition. - expiratory reserve volume (ERV): -inspiratory reserve volume (IRV): -tidal volume (TV): -residual volume (RV):

- expiratory reserve volume (ERV): amount of air that can be forcefully expired after expiration of tidal volume -inspiratory reserve volume (IRV): amount of air that can be forcefully inspired after inspiration of tidal volume -tidal volume (TV): amount of air inspired/expired with each quiet breath -residual volume (RV): volume of air remaining in the lungs after forceful expiration

Match each respiratory capacity with its definition. - total lung capacity (TLC): - vital capacity (VC): - inspiratory capacity (IC): - functional residual capacity (FRC):

- total lung capacity (TLC): vital capacity plus residual volume - vital capacity (VC): maximum amount of air that can be expelled after a maximal inspiration - inspiratory capacity (IC): air inhaled after a quiet expiration - functional residual capacity (FRC): air left in lungs after normal expiration

List in order the steps that result in blood CO2 levels having an effect on central chemoreceptors.

1. CO2 crosses blood barrier 2. CO2 combines with water to form carbonic acid. (H2CO3) 3. Carbonic acid ionized, releasing hydrogen ions (H+). 4. Hydrogen ions stimulate central chemoreceptors.

What is the partial pressure of oxygen (Po2) in alveolar air

104 mm Hg

The partial pressure of oxygen (Po2) in alveolar air is

104 mmHg

A fully loaded hemoglobin molecule carries

4 oxygen molecules

The PO2 in the tissue fluid is ______ mm Hg

40

The partial pressure of oxygen (PO2) of blood entering the pulmonary capillaries is ______ mm Hg.

40

The diffusion gradient for the exchange of CO2 at the alveoli is as follows: P co2 in pulmonary capillaries is _______ mm Hg and the Pco2 in alveolar air is _____ mmHg

45 40

On average, the partial pressure of carbon dioxide (PCO2) entering the pulmonary capillaries is ______ mm Hg. The PCO2 of alveolar air is ______.

45; 40

What is the adult value for resting tidal volume?

500 mL

How much of the carbon dioxide in the blood is dissolved in plasma?

7%

Describe the interaction between blood oxygen levels and the regulation of respiration.

Blood oxygen has little direct effect on central chemoreceptors.

Indicate the three statements that apply to the regulation of breathing.

Blood oxygen levels must be very low to trigger or stimulate the peripheral chemoreceptors. Low blood oxygen levels have little direct effect on the central chemoreceptors. Oxygen levels play only a minor role in the control of normal respiration.

Which equation correctly illustrates what happens in the tissues, as carbon dioxide is picked up by the blood?

CO2 + H2O → H2CO3 → H+ + HCO3-

True or false: A sphygmomanometer is a medical device used to measure air volumes in order to evaluate the course of respiratory illnesses.

False

Which of these reactions occurs in the alveolar capillaries? (The other occurs in the tissues.)

H+ + HCO3- → H2CO3 → CO2 + H2O

Why do the lungs expand as the rib cage lifts and the diaphragm contracts?

Lung tissue adheres to the thoracic wall due to the pleural fluid and pleural membranes; when the thoracic wall moves, the lungs are pulled along.

95 mm Hg is the partial pressure of ____ in systemic arterial blood.

O, O2, or oxygen

Why does surface tension develop within the watery fluid lining the alveoli?

Polar water molecules are attracted to each other.

Why do normal fluctuations in blood oxygen levels have little influence on respiratory control?

Systemic venous blood is still 75% saturated, so oxygen is still abundant.

True or false: Lung expansion in response to movements of the diaphragm and chest wall depends on the pleural membranes.

True

True or false: Pleural (serous) fluid holds the pleural membrane layers together during breathing.

True

True or false: The partial pressure of oxygen (PO2) in blood entering the alveolar capillaries is 40 mm Hg.

True

Define hyperventilation.

Ventilation that exceeds needs of the body, lowering blood CO2 levels.

Which lung capacity is calculated by adding the tidal volume (TV), inspiratory reserve volume (IRV), and the expiratory reserve volume (ERV)?

Vital capacity (VC)

What are alveoli?

air sacs

An increase in blood CO2 or a decrease in blood pH will lead to which change in respiration?

alveolar ventilation will increase

Gas exchange between the air and the blood occurs at the _____ of the lungs

alveoli or alveolus

Which structure is the site of gas exchange in the lungs?

alveolus

Define minute ventilation.

amount of air moved into airways per minute

Name the space occupied by air that remains in the trachea, bronchi, and bronchioles after inhalation.

anatomic dead space

The space occupied by inhaled air not used for gas exchange is called the ______ dead space. The inhaled air remains in the trachea, bronchi, and bronchioles.

anatomical or anatomic

Carbon dioxide is transported as different forms in the blood. What is the most common form?

as bicarbonate ions

Why does carbon dioxide diffuse from the tissues into the capillaries?

because the PCO2 is higher in the tissues than in the blood

One way in which carbon dioxide can be carried to the lungs is as part of _______ ions

bicarbonate

Which method is used to carry approximately 98% of the oxygen in the blood?

bound to the iron portion of the hemoglobin molecules in red blood cells

The control centers for respiration (respiratory areas) are located in which part of the central nervous system?

brainstem

Which components are part of the lower respiratory system?

bronchial tree trachea lungs

Which of the following crosses the blood-brain barrier, interacts with water, and ultimately results in the production of hydrogen ions?

carbon dioxide (CO2)

When carbon dioxide combines with water, the compound ______ is formed.

carbonic acid

List two locations for the peripheral chemoreceptors that monitor CO2, pH, and oxygen levels of the blood.

carotid bodies aortic bodies

The hollow space behind the nose that is divided medially by the nasal septum is the nasal

cavity

The hollow space just behind the nose is called the nasal

cavity

The ______ chemoreceptors respond to hydrogen ions, but not to carbon dioxide.

central

An increase in acidity, PCO2, or temperature will ______ the oxygen saturation of hemoglobin.

decrease

The function of surfactant is to ______ the surface tension of the fluid lining the alveoli, reducing the tendency for the alveoli to collapse.

decrease

Indicate two changes that will trigger increased alveolar ventilation.

decreased blood pH increased blood levels of CO2

Indicate three factors that will cause an increase in the release of oxygen from oxyhemoglobin in the tissues.

decreased pH increased temperature increased PCO2

Air moves out of the lungs when the size of the thoracic cavity ______.

decreases

What effect does contraction of the diaphragm have on intra-alveolar pressure?

decreases intra-alveolar pressure

List three forms by which carbon dioxide is transported in the blood.

dissolved in plasma as bicarbonate ions as carbaminohemoglobin

As blood passes through the tissue (systemic) capillaries, oxygen is ______ because the Po2 in the tissue fluid is ______ than the Po2 in the blood of those capillaries.

dropped off; lower

The type of tissue making up the lungs accounts for ______, which contributes to the tendency for the lungs to return to their resting size after they have been stretched.

elastic recoil

What is the anatomical term for the nostrils of the nose?

external nares

True or false: CO2 and O2 compete for the same binding sites on hemoglobin molecules.

false

Hemoglobin is composed of ______ globin subunits and ______ heme units.

four; four

While oxygen binds to the heme groups of hemoglobin, carbon dioxide binds to the ______ of hemoglobin.

globin

The protein portion of hemoglobin is called _____ and it is composed of ____ polypeptide chain(s).

globin 4

The difference in distribution of gases between two areas, such as within the alveoli and alveolar capillaries, is called the partial pressure

gradient

Almost all of the oxygen diffusing into the alveolar capillaries becomes bound to the protein called ________ on the surfaces of red blood cells.

hemoglobin

Blood flowing through the tissue capillaries picks up carbon dioxide because active tissues, such as skeletal muscle, have a relatively ______ PCO2 compared to the blood.

high

A gas will diffuse from an area of ______ partial pressure for the gas to an area of ______ partial pressure.

higher; lower

Carbonic acid dissociates into which two products?

hydrogen ion bicarbonate ion

Considering the factors that influence respiration, the two that are more important in respiratory regulation are ______ and ______.

hydrogen ions carbon dioxide

The central chemoreceptors in the medulla oblongata respond to ______.

hydrogen ions only

The central chemoreceptors respond to ______, not to ______.

hydrogen ions; carbon dioxide

Which of the following would cause a decrease in carbon dioxide levels in the blood?

hyperventilation

A higher-than-normal breathing rate that lowers blood CO2 concentration is termed

hyperventilation, tachypnea, or hyperventilating

Hyperventilation causes carbon dioxide levels in the blood to ______.

increase

Rate and depth of breathing will increase if carbon dioxide levels are ______ in the blood.

increased

What happens to respiration when blood levels of carbon dioxide increase?

increased alveolar ventilation

Contracting the external intercostal muscles ______ the size of the thoracic cavity.

increases

The oxygen saturation of hemoglobin ______ as the PO2 increases.

increases

Control of respiration is based on input from ______ that monitor lung inflation and ______ that monitor O2, CO2, and pH.

mechanoreceptors; chemoreceptors

The ______ respiratory center includes two groups of neurons called the ventral respiratory group (VRG) and the dorsal respiratory group (DRG).

medullary

The amount of air moved into the airways each minute is called the

minute ventilation

Define ventilation.

movement of air into and out of lungs

Air movements other than breathing, such as coughing or sneezing to clear air passages, are called

nonrespiratory or non-respiratory movements

The openings through which air can enter and leave the nasal cavity are called the external nares or

nostrils

Decreasing the size of the thoracic cavity causes air to move ______ the lungs.

out of

Because of its abundance in both arterial and venous systemic blood, ______ does not affect respiration until its blood levels get abnormally low.

oxygen

In order for decreased ______ to play a role in the respiratory control mechanism involving peripheral chemoreceptors, blood levels of this component must drop to 50% of normal.

oxygen

The oxygen saturation of hemoglobin increases as the partial pressure of ______ increases.

oxygen

What binds to the iron atoms found within a hemoglobin molecule?

oxygen

Which of the following has the LEAST influence on the rate of respiration?

oxygen concentration in the blood

The respiratory system functions to obtain ______ and remove ______.

oxygen; carbon dioxide

As oxygen dissolves in blood, it rapidlhy combines with hemoglobin, forming a new compound called

oxyhemoglobin

When oxygen combines with hemoglobin, the resulting molecule is called

oxyhemoglobin

Which name is given to hemoglobin that is carrying oxygen atoms?

oxyhemoglobin

Central chemoreceptors monitor the ______ of the brain.

pH

What is directly monitored by the central chemoreceptors?

pH of the brain

Which term describes the amount of pressure each gas in a mixture contributes to the overall gas pressure?

partial pressure

In a mixture of gases, the amount of pressure each gas contributes to the total pressure is called the

partial pressure of the gas

During quiet breathing, expiration is a(n) ______ process, since it relies on the recoil of elastic tissues to change thoracic cavity volume.

passive

The respiratory control mechanism involving ______ chemoreceptors will only be triggered when blood levels of oxygen drop to 50% of normal.

peripheral

When blood oxygen levels decrease dramatically, ______ chemoreceptors in the carotid and aortic bodies stimulate the respiratory centers of the brain to _______ breathing rate.

peripheral increase

The aortic bodies and carotid bodies are locations for

peripheral chemoreceptors

Attraction between water molecules in the serous fluid in the pleural cavity causes the ______ to stick together.

pleurae

Which is a passive process?

quiet expiration

List three factors that allow for the lungs to undergo normal expiration (reduction of lung volume to resting state).

recoil of compressed abdominal organs elastic tissue in the lungs and thoracic wall surface tension within alveoli

Which are three functions of the respiratory system?

remove CO2 from the body regulate blood pH participate in gathering olfactory information

The amount of air that remains in the lungs after a maximal forced expiration is called the

residual volume

The respiratory volume called the ______ cannot be directly measured using spirometry.

residual volume

Which volume is defined as the amount of air that remains in the lungs after a maximal forced expiration?

residual volume (RV)

What is the correct formula for calculating total lung capacity (TLC)?

residual volume + vital capacity (RV + VC)

Both inspiration and expiration are under the control of groups of neurons in the brainstem that comprise the

respiratory or respiration areas

What is the name of the medical device used to measure air volumes (except the residual volume)?

spirometer

In the alveoli, the attraction of water molecules to each other creates a force called _______ ________ that makes it difficult to inflate the alveoli and may collapse them.

surface tension

The substance that functions to reduce surface tension within alveoli is called

surfactant

It is necessary that the respiratory membrane be ______ in order to allow adequate gas exchange.

thin

The volume of air that enters or leaves the airways and alveoli during a respiratory cycle is called the

tidal volume

Which three of the respiratory volumes can be directly measured using spirometry?

tidal volume expiratory reserve volume inspiratory reserve volume

Name the respiratory volume that is defined as the amount of air moved in, then out, during a single respiratory cycle.

tidal volume (TV)

Which respiratory volume has a normal value of 500 mL?

tidal volume (TV)

Consider the bicarbonate reaction involving the intermediary carbonic acid. The production of bicarbonate ion occurs in the ______ while the production of CO2 occurs in the ______.

tissues; lungs

Which of these calculated volumes typically has the greatest value?

total lung capacity

Which of these structures is part of the lower respiratory system?

trachea

True or false: The respiratory membrane is very thin so that oxygen and carbon dioxide can easily diffuse across it.

true

The medullary respiratory center is composed of which two areas?

ventral respiratory group dorsal respiratory group

The purposes of nonrespiratory movements of air include ______.

verbal communication clearing air passages expressing emotions

The maximum volume of air a person can exhale after taking the deepest breath possible is called the

vital capacity or VC

Carbon dioxide combines with ____ to form carbonic acid.

water