Lectures 19-21

Front 1

Robert Boyle

Back 1

RobertBoyle showed that both animals and flames died in a vacuum indicating that aircontained something (oxygen) that is required both to maintain life and to keepa candle burning

Front 2

Joseph Priestly

Back 2

Examined the ability of gases to support life: Most gases cannot support life

Mice survived when placed in gas produced by heating mercuric oxide (oxygen)

Mice lived longer if plant material is present in the container (oxygen)

Front 3

Antoine Lavoisier

Back 3

Experimented with Priestly's life-supporting gas: Named the gas "oxygen"

Discovered that animals and burning coal consume O2 and release CO2 and heat.

Demonstrated that the amount of heat produced relative to O2 uptake is about the same for animals and burning coal.

Front 4

Respiratory Surface

Back 4

site of oxygen, carbon dioxide exchange.

(must be moist & have a large surface area)

Front 5

2-step process of a coupled respiratory &

circulatory system

Back 5

step 1: exchange between respiratory medium (Alveoli) and circulatory system

step 2: exchange between circulatory system and interstitial fluid bathing cells

Front 6

Advantages (1) & Disadvantages (3) of respiration in aquatic animals

Back 6

Advantage:

respiratory surfaces always moist

Disadvantages:

O2 concentration relatively low in ocean

exchange must be extra efficient

needs to expend energy for gas exchange

Front 7

ventilation

Back 7

any method of increasing contact between the respiratory medium and the respiratory surface

(usually requires energy)

Front 8

counter-current exchange through gills

Back 8

water flows in through the mouth, out through the gills while blood flow in thin lamella passes water in opposite direction. The water warms the blood which warms the body.

Front 9

Advantages (3) & Disadvantages (1) of respiration in terrestrial animals

Back 9

Advantages:

higher concentration of O2

O2 and CO2 diffuse faster in air

air is easier to move & requires less energy

Disadvantage:

loss of water by evaporation

Front 10

Human anatomy pathway of respiratory system

Back 10

mouth --> pharynx --> larynx --> trachea --> bronchi --> bronchioli --> alveoli

Front 11

pleural sac

Back 11

thin, fluid-filled sac that separates the lungs and chest wall. always has negative pressure that keeps the lungs bigger and the chest wall

smaller.

Front 12

delta pressure =

Back 12

intrathoracic pressure - air pressure

= (intrapleural + intra-alveolar) - air

Front 13

Inspiration: process

Back 13

ACTIVE process.

1. diaphragm contracts, lungs expand

2. intercostal muscles contract, ribs expand

3. lung volume increases

4. air flows in through oral cavity

Front 14

Inspiration: pressure levels

Back 14

intra-alveolar pressure = negative

intrapleural pressure = negative

air pressure = positive

delta pressure = negative

Front 15

Expiration: process

Back 15

PASSIVE process.

1. diaphragm relaxes, lungs shrink

2. intercostal muscles relax, ribs relax

3. lung volume decreases

4. air flows out of oral cavity

Front 16

Expiration: pressure levels

Back 16

intra-alveolar pressure = positive

intrapleural pressure = negative

air pressure = positive

delta pressure = positive

Front 17

Tidal volume

Back 17

breathing normally at rest. ~500mL

Front 18

Expiratory reserve volume

Back 18

actively exhaling air as much as you can. ~1100mL

Front 19

Residual volume

Back 19

volume of air remaining at lungs at the end of a forced exhalation. ~1200mL

Front 20

Dead space

Back 20

volume of air remaining in airways at the end of each exhalation. ~150mL

Front 21

Inspiratory reserve volume

Back 21

actively inhaling air as much as you can. ~3000mL

Front 22

Vital capacity

Back 22

the total volume that is available for the organism to use. (tidal + expiratory reserve +

inspiratory reserve = ~4600mL)

Front 23

Total pulmonary ventilation rate

Back 23

Tidal volume * respiratory rate

(500mL/breath * 12 breaths/min = 6000mL)

Front 24

Alveolar ventilation rate

Back 24

Tidal volume - dead space * respiratory rate

(500mL - 150mL * 12 breaths/min = 4200mL)

Front 25

Frick's Law of Diffusion

Back 25

delta Qs/delta t = Ds * (C2-C1)

Front 26

Partial pressure of O2 and CO2 in AIR

Back 26

O2 = 160mmHg

CO2 = 0.25mmHg

Front 27

Respiratory pigments

Back 27

carrier proteins that transport oxygen through blood. include hemoglobin (humans) and

hemocyanin (arthropods/mollusks)

Front 28

Hemoglobin structure

Back 28

4 protein subunits, each with iron in the center binding oxygen for each subunit.

Front 29

___% of oxygen is dissolved in blood

___% of oxygen is bound to hemoglobin

Back 29

2% dissolved

98% hemoglobin

Front 30

Red blood cells

Back 30

cells packed with hemoglobin

Front 31

Oxygen-hemoglobin dissociation curve

Back 31

Thehigher the partial pressure of oxygen, the more oxygen saturation (binding) ofhemoglobin

lungs: ppO2 = 100mmHg, 99% saturation

tissues at rest: ppO2 = 40mmHg, 75% saturation

tissues exercise: ppO2 = 10mmHg, 10% saturation

Front 32

Bohr shift

Back 32

Decreasedbinding of oxygen to hemoglobin, high ppCO2, low pH

(see picture)

Front 33

Myoglobin

Back 33

respiratory pigment in muscle that rely on

aerobic metabolism (red muscle/dark meat)

has a single heme group instead of four

much higher affinity for O2 than hemoglobin

O-H dissociation curve shifts to the left

Front 34

___% of CO2 is dissolved in blood

___% of CO2 is bound to hemoglobin

___% of CO2 contributes to the bicarbonate

buffer system

Back 34

7% dissolved

23% hemoglobin

70% bicarbonate

Front 35

Pons respiratory center

Back 35

modulates medulla respiratory center

Front 36

Medulla respiratory center

Back 36

generates the respiratory rhythm by

responding to sensory feedback and interacting with respiratory motoneurons

Front 37

Hering-Breuer reflex

Back 37

inspiratory neurons in medulla stimulate respiratory motoneurons which trigger respiratory muscles to expand which activates stretch

receptors in bronchi, sending negative feedback to the respiratory center to end inspiration

Front 38

Peripheral chemoreceptors

Back 38

located in carotid bodies, aortic arch, and fish gills.

activated by a decrease in ppO2 and an increase in ppCO2, although it has to be a significant change.

Front 39

Central chemoreceptors

Back 39

very sensitive, fast, and crucial for respiratory

regulation

located in the medulla oblongata

activated by a decrease in pH (increase in [H+]) of the CSF

CO2 and H+ in CSF bind to central chemoreceptors

response: respiratory control centers increases ventilation to increase ppO2 and decrease pCO2

Front 40

Shallow-water blackout

Back 40

sudden loss of consciousness while diving caused by hyperventilation before diving and physical activity while diving, among other things.

Front 41

hyperventilation

Back 41

increases ppO2 without changing O2 content

decreases ppCO2 and CO2 content

decreases respiratory drive

longer breath-holding time

Front 42

hypoventilation

Back 42

decreases ppO2 and slightly decreases O2

content

increases ppCO2 and CO2 content & [H+]csf

increases respiratory drive

shorter breath-holding time