Unit 8: The Respiratory System - Gas Exchange and Transport & Unit 9: Regulation - The Rate of Respiration and Blood pH (Module 2)

dalton’s law

the concept that within a mixture of gases, each gas within the atmosphere exerts its own pressure, as if no other were present

partial pressures

atmospheric pressure = total of ____

faster

the greater the difference in partial pressure, the ____ the rate of diffusion

ok

review how dalton’s law applies to external and internal respiration (look at drawing in notes & explain to self)

exercise, altitude, emphysema, diffusion distance

what are some things that influence the rate of gas exchange?

rate of diffusion increases because PO2 is lower and CO2 is higher in the pulmonary capillaries

how does exercise influence rate of gas exchange?

PO2 decreases at higher altitudes, so the rate of diffusion decreases

how does altitude influence rate of gas exchange?

emphysema

integrity of the alveolar wall is damamged

less surface area for gas exchange, slowing the rate of diffusion

how does emphysema influence rate of gas exchange?

if the pulmonary capillaries are farther from the alveoli (due to liquid) the rate of diffusion slows

how does diffusion distance influence rate of gas exchange?

pulmonary edema

example of something that would cause diffusion distance to slow rate of diffusion

dizziness, fatigue, headache

what are some symptoms of altitude sickness?

increase RBCs by secreting more EPO from the kidneys

how might the body combat altitude sickness?

oxyhemoglobin

Hb + O₂ = ________

4

how many heme groups does each hemoglobin molecule have?

partial pressure of O2, pH of the blood, PCO2, temperature

transport of O2 is influenced by…

increases

as Po2 increases, Hb-O₂ _______ (lungs)

O2 breaks off from Hb-O2

as PO2 decreases… (in the tissues)

increases

as pH decreases, hydrogen ions ______

lose its affinity for O2

a decrease in pH causes Hb to what?

Bohr effect

the relationship between low blood pH and the release of O2 from Hb

bind more to O2

as pH increases, Hb will…

releases O2

As PCO2 increases, Hb…

increase in PCO2 and decrease in pH

what two things cause Hb to release O2?

CO2 +H2O → H2CO3 → HCO3- + H+

Bohr Effect Equation

carbonic acid

what is the name for H2CO3

bicarbonate

what is the name for HCO3-?

lose its affinity for O2

an increase in temperature causes Hb to what?

200

CO has ____ times the affinity that O2 has for Hb

HCO3-

where is most CO2 carried?

chloride shift

how is HCO3- released from RBCs?

carbaminohemoglobin (Hb-CO2)

13% of Co2 is carried in blood as ____

PCO2

carbaminohemoglobin is formed as ____ increases

blood plasma

9% of the body’s CO2 is dissolved where?

ventral respiratory group (VRG), pneumotaxic area, apneustic area

where is regulation of breathing carried out?

VRG

which nuclei in the brain stem is in the medilla?

Pneumotaxic and apneustic area

which major nuclei are in the pons?

inspiratory area

stimulates diaphragm and external intercostals via the phrenic nerve and intercostal nerves

forceful inhalation

during _____ the expiratory area is stimulated to generate forceful exhalation

pneumotaxic area

sends inhibitory signals to prevent lungs from overfilling; causes short quick breaths and increases rate of respiration

apneustic area

sends signals to prolong depolarization; causes long deep breaths and decreases the rate of respiration

higher brain areas, proprioceptors, stretch receptors, temperature

things that influence the regulation of breathing

proprioceptors

when activated, they send signals to inspiratory area in anticipation for movement

stretch receptors

inhibit apneustic when the ones in the bronchioles are activated

increases

as temperature increases, respiration ___

decrease

Categorize whether the following decreases or increases oxyhemoglobin levels?

Decreased pH

decrease

Categorize whether the following decreases or increases oxyhemoglobin levels?

increased temperature

decrease

Categorize whether the following decreases or increases oxyhemoglobin levels?

heavy exercise

increase

Categorize whether the following decreases or increases oxyhemoglobin levels?

increased PO2

increase

Categorize whether the following decreases or increases oxyhemoglobin levels?

decreased PCO2

bicarbonate ion

the majority of CO2 in the blood is carried as _____

carbonic anhydrase

the reaction between CO2 and H2O to H2CO3 is catalyzed by _____

chloride shift

the _____ is an anion exchange that takes place in RBCs as a mechanism to transfer bicarbonate ions out of the cell

carbaminohemoglobin

the combination of CO2 and a protein known as ______ is abbreviated HbCO2

dissolved gas

less than 10% of CO2 is transported as _____

Haldane

the ability of CO2 to bind to deoxygenated hemoglobin more readily than it does oxyhemoglobin is referred to as the ______ effect

decreases

Indicate whether the following decreases or increases respiratory rate

blood levels of hydrogen ions decrease

decreases

Indicate whether the following decreases or increases respiratory rate

blood pH increases

increases

Indicate whether the following decreases or increases respiratory rate

Arterial PO2 drops below 60 mmHg

increases

Indicate whether the following decreases or increases respiratory rate

levels of CO2 in the blood increase

increases

Indicate whether the following decreases or increases respiratory rate

blood levels of hydrogen ions increase

increases

Indicate whether the following decreases or increases respiratory rate

blood pH decreases

alveolar

indicate whether the following takes place in the alveolar or systemic capillaries

decreasing carbon dioxide levels decrease the levels of HHb (deoxyhemoglobin)

alveolar

indicate whether the following takes place in the alveolar or systemic capillaries

carbonic acid in RBCs concerts back to CO2 and water

alveolar

indicate whether the following takes place in the alveolar or systemic capillaries

CO2 diffuses from the blood

alveolar

indicate whether the following takes place in the alveolar or systemic capillaries

oxygen is diffusing into the blood

systemic

indicate whether the following takes place in the alveolar or systemic capillaries

chloride ions shifts into the RBC

systemic

indicate whether the following takes place in the alveolar or systemic capillaries

CO2 binds to plasma proteins

systemic

indicate whether the following takes place in the alveolar or systemic capillaries

CO2 is diffusing into the blood

systemic

indicate whether the following takes place in the alveolar or systemic capillaries

carbonic anhydrase is increasing the amount of carbonic acid

central chemoreceptors

the pH of the cerebrospinal fluid is monitored by which of these brainstem centers?

medulla oblongata

the vagus and glossopharyngeal nerves carry afferent signals from peripheral chemoreceptors to a chemosensitive area in the ____

peripheral chemoreceptors

found in the carotid artery and arch of aorta

hypoxemia, hypercapnia, acidosis

what do peripheral chemoreceptors monitor (in the blood)?

central chemoreceptor

found in the medulla, regulates CSF

hypercapnia, acidosis, NOT hypoxemia

what does the central chemoreceptor monitor for (and not)?

hypercapnia

the increase in PCO2 above 40 mmHg; also results in excess H+

signal inspiratory area to increase rate and depth of breathing

how does the peripheral chemoreceptor respond to hypercapnia?

decrease; ‘blow off’ excess CO2

does hyperventilation increase or decrease CO2 levels?

no

do the chemoreceptors do anything for hypocapnia

7.35-7.45

what is considered normal blood pH?

CO2; O2

regulation of breathing depends more on ____ than _____

more

if the rate of respiration increases, more or less CO2 is exhaled?

less

if the rate of respiration decreases, more or less CO2 is exhaled?

increase (become alkaline/basic)

if the rate of respiration increases, what will pH do?

left

is the rate of respiration increases, which way will bohr effect equation go?

right

if the rate of respiration decreases, which way will the borh effect equation go?

decrease (become acidic)

if the rate of respiration decreases, what will pH do?

anxiety or asthma attack, hyperventilation

what could cause the rate of respiration to increase?

holding breath

what could cause rate of respiration to decrease?

inspiratory area; increasing

if blood pH decreases, chemoreceptors in the aortic and carotid bodies activate the __________, which acts to rid CO2 by _____ the rate of respiration

negative

do the chemoreceptors operate under negative or positive feedback?

no

if blood pH increases, __ impulses are sent to the inspiratory area

hemoglobin and bicarbonate

two examples of buffers

lower than 7.35

respiratory acidosis is a pH of ___

respiratory acidosis

abnormally high levels of CO2 (which also increases H+ and HCO3-

respiratory acidosis

leads to decreased activity of the nervous system, may become disoriented; comatose → death

injury to the medulla and to muscles

what can respiratory acidosis cause?

pulmonary edema

collection of fluids in alveoli and lungs, increasing pulmonary capillary pressure and blocking exchange of O2/CO2

CHF, pneumonia

some causes of pulmonary edema