Lab 4

Question 1

What is anatomical dead space (aka conducting zone)? What about the transitional/respriatory zone?

Answer 1

anatomical dead space: The volume of the respriatory tract that does not participate in gas exchange

Question 2

What is the difference between alveolar pressure, intra-pleural pressure, and transmual
pressure?

Answer 2

Alveolar pressure: Pressure within alveoli.
intra-pleural pressure: Pressure within plural sac. About 4 mmHg less than atmospheric pressure
transmural pressure: difference betwen intral-plural space and intra-alveolar space

Question 3

What is the difference between tidal volume, IRV, ERV, and RV?

Answer 3

Tital volume: amount of air exchange on a normal respiration
IRV: inspiratory reserve volume: additional volume that can be inhaled on inspiration
ERV: Expiratory reserve volume: additional volume used during maximal expiration
RV: residual volume: volume of gas left after maximal expiration

Question 4

What is the difference between total lung capacity (TLC), functional residual capacity (FRC), vital capacity (VC), and inspiratory capacity (IC)?

Answer 4

TLC: total volume of air in lungs after maximal inspiration
FRC: volume of gas remaining after normal tidal expiration. FRC = RV + ERV
VC: volume of air expelled after maximal inspiration followed by expiration. VC = ERV + TV + IRV
IC: maximal volume of air that can be expired. IC = TV + IRV

Question 5

What is the Hering-Breuer reflex

Answer 5

When there is an increase in the stretch of smooth m. tissue in the lungs, there will be an inhibitory response from inspiratory n.s. Visa versa if decrease in observed.

Question 6

What is hyperpnea and what is it caused by?

Answer 6

increase in ventilation matching an increase in
metabolic activity, such as exercise

Question 7

What does IR stand for? How is it measured?

Answer 7

-IR is internal (cellular) respriation.
- It is meausred via the respiratory quotient. RQ=CO2 output/ O2 input
-glucose’s RQ ~ 1

Question 8

What are the four steps of external to internal respiration?

Answer 8

1) Ventilation of air from the body
2) Gas exchange between alveoli and capillaries
3) transport of gasses thru the blood
4) gas exchange between capillaries and tissues (IR)

Question 9

What is the primary function of the respiratory system? How about the secondary ones?

Answer 9

Primary function: gas exchange
secondary function: water and heat balance, acid-base balance, immunity, vocalization, production of enzymes, smell

Question 10

What is the difference between type I and type II alveoli?

Answer 10

Type I: covers 95% of SA. Primarily used in gas exchange
Type II: covers 5% of SA. used in pulmonary surfactant secretion

Question 11

Formula for minute ventilation, dead space ventilation, and alveolar ventilation

Answer 11

VE= minute ventilation = TV * RR
Dead space ventilation = DS(vol)RR
Alveolar ventilation = (TV - DSvol)RR= V(E) - V(DS)

Question 12

What are the three major ways that CO2 can enter the blood?

Answer 12

1) 8% form bicarbonate
2) 65% will rxt with enzymes to form bicarbonate
3) 27% will enter a RBC and form a carbaminobemoglobin with the terminal amine of a hgb

Question 13

Where are the central chemoreceptors? how about the peripheral chemoreceptors? How about the stretch receptors? (for respiratory system)

Answer 13

Central = medulla oblongata
peripheral = aortic arch/ carotid body
stretch= lung parenchyma

Question 14

Which area of the brain controls respiration?

Answer 14

the medulla and pons

Question 15

What does hypoventilation lead to in pCO2 in the blood? What about hyperventilation? What is this called? What does this do to blood pH?

Answer 15

hypoventilation = increase in arterial pCO2 (hypercapnia). Increases pH
hyperventilation = decrease in pCO2 (hypocapnia). Decrease pH

Question 16

What does hypoxia mean? What does it correspond with in blood pH?

Answer 16

decrease in arterial pO2? decrease in pH?

Question 17

What does a decrease in pH do to ventilation rate? Why

Answer 17

Decrease in pH –> increase in pCO2. This increases ventilation rate.

Question 18

What does the medullary respiratory center sense?

Answer 18

pCO2

Question 19

What innervates the lung parenchyma/smooth muscle stretch receptors?

Answer 19

the vagus n.

Question 20

What is the Bohr effect?

Answer 20

It is when the hgb molecule shifts conformation in low pH environments to become oxygen releasing. Visa versa in high pH environments

Question 21

Which breath hold had the highest breath hold time? normal breathing, re-breathing, or hyperventilation? Why?

Answer 21

hyperventilation due to the low pCO2 it produces in the blood

Question 22

What does the dorsal receptor group do? WHat does the ventral respiratory group do? WHere are they?

Answer 22

-They are in the medulla oblongata
-Dorsal: receives info from central and peripheral chemoreceptors
ventral: regulates breathing from the dorsal

Question 23

What gas has more effect on ventilation rate? CO2 or O2?

Answer 23

CO2

Question 24

What is the normal percent for oxygen saturation at rest?

Answer 24

100%

Question 25

When do stretch receptors trigger respriatory drive? When do only chemoreceptor trigger respriatory drive?

Answer 25

Chemoreceptors only at rest. stretch receptors activate when forced (accessory) inspriation happens.