Chapter 22 Flashcards - New

1.     Pulmonary ventilation – the act of _______; ______ and ______

breathing

Inhalation and exhalation

1. External respiration – the exchange of o2 and CO2 between the ______ and the __________

a. Inside of lungs are _______ (which is why its called external respiration)

3. Internal respiration – exchange of gasses between the ____ and the ____, at the _____

1. External respiration – the exchange of o2 and CO2 between the lungs and the blood inside the lungs

a. Inside of lungs are ____outside the body__ (which is why its called external respiration)

3. Internal respiration – exchange of gasses between the blood and the tissues, at the tissues

Upper respiratory system (basic functions) Pt 1

1. Nose & nasal cavity – function (filters________________)

2. Paranasal sinuses – These are __________ that make the _________ and also help with ____________________ (lined with epithelial tissue)

3. Pharnyx

a. Nasopharynx - Creates _____, and _____ catches things and moves things along

ii. ________ prevents movement of food into nose during swallowing

iii. _____________– part of the lymphatic system – traps things that come into the body and allows our immune system to be exposed to it

1. Nose & nasal cavity – function (filters air to breathe in)

2. Paranasal sinuses – These are open spaces that make the skull lighter and also help with warming and moistening the air (lined with epithelial tissue)

3. Pharnyx

a. Nasopharynx - Creates mucous, Cilia catches things and moves things along

ii. ___Uvula__ prevents movement of food into nose during swallowing

iii. Pharyngeal tonsil – part of the lymphatic system – traps things that come into the body and allows our immune system to be exposed to it

Upper respiratory system (basic functions) Pt 2

a. Oropharynx –

i. Primarily___stratified squamous epithelial_ tissue

1. Provides ________________

ii. Palatine tonsils – exposed to anything that __________________________

iii. Lingual tonsil - Expose immune system to whatever comes in through our ______

b. Laryngopharynx – at the back of the throat below the mouth

1. Two tubes that split at the laryngopharynx

2. Posterior tube = continuous with the _____

3. Anterior tube = enters towards the ____ and then the ______

Upper respiratory system (basic functions) Pt 2

a. Oropharynx –

i. Primarily___stratified squamous epithelial_ tissue

1. Provides resistance to abrasion

ii. Palatine tonsils – exposed to anything that we breathe in through our mouth or swallow

iii. Lingual tonsil - Expose immune system to whatever comes in through our mouth

b. Laryngopharynx – at the back of the throat below the mouth

1. Two tubes that split at the laryngopharynx

2. Posterior tube = continuous with the esophagus

3. Anterior tube = enters towards the larynx and then the trachea

Why do sinus infections often lead to ear infections?

Opening of the pharyngotympanic tube/eustachian tube, which connects to the back of the nose at the top of the throat. Nasal cavity and inner ear are continuous, meaning pressure of the inner ear and pressure of the nasal cavity are continuous as well. Sinus infections can spread to the ear and vice versa

Larynx: Functional Anatomy

i. Holds ________ (primarily hyaline cartilage (stiff))

ii. Directs _______into proper locations

1. Epiglottis – when we swallow the _____ folds down, the ____ folds up, and the _____ blocks the opening into the larynx and the trachea (forcing the food down the esophagus)

iii. Voice production – thin folds of tissue inside the larynx that vibrate when stiffened and air comes out (how we produce speech)

1. True vocal cords – ___________

2. False vocal cords – fold shut so that anything that is __________________

i. Holds airway open (primarily hyaline cartilage (stiff))

ii. Directs food/air into proper locations

1. Epiglottis – when we swallow the epiglottis folds down, the larynx folds up, and the epiglottis blocks the opening into the larynx and the trachea (forcing the food down the esophagus)

iii. Voice production – thin folds of tissue inside the larynx that vibrate when stiffened and air comes out (how we produce speech)

1. True vocal cords – produce speech

2. False vocal cords – fold shut so that anything that is small enough to bypass the epiglottis gets blocked

Trachea

a. Mucosal layer

i. ___Pseudo-stratified ciliated columnar epithelial_____ tissue

1. Contains goblet cells, cilia, and seromucous glands that help the trachea do its job well

ii. Cilia* - the inside of the trachea is lined with mucous that traps what we breathe in, and the cilia ____________________

b. Submucosal layer

i. Seromucous glands – produce ____________ that is more effective at lining things rather than being moved up and out

1. If you smoke, it burns the cilia and then the goblet cells and seromucous glands (causes dry hacking cough)

c. Adventitia

i. _________________ rings hold trachea open

1. Significance of “C” shape – _________

a. Mucosal layer

i. ___Pseudo-stratified ciliated columnar epithelial_____ tissue

1. Contains goblet cells, cilia, and seromucous glands that help the trachea do its job well

ii. Cilia* - the inside of the trachea is lined with mucous that traps what we breathe in, and the cilia move it upward to be coughed out

b. Submucosal layer

i. Seromucous glands – produce sheet-like mucous that is more effective at lining things rather than being moved up and out

1. If you smoke, it burns the cilia and then the goblet cells and seromucous glands (causes dry hacking cough)

c. Adventitia

i. ____Hyaline Cartilage___ rings hold trachea open

1. Significance of “C” shape – holds the trachea open but the c-shape allows for the esophagus to expand and lets food move on through

Bronchial Tree

i. Right/left primary bronchi – carry air into __________

ii. Lobar/secondary bronchi - each carry to ___________________

1. __ on right ______ on left because the left only has 2 lobes (because the heart is larger on the left side)

iii. Segmental/tertiary bronchi

iv. Etc…

v. Bronchioles

1. Smaller than ____ diameter

vi. Terminal bronchioles

1. Smaller than ______ diameter

i. Right/left primary bronchi – carry air into their separate lungs

ii. Lobar/secondary bronchi - each carry to one of the lobes of the lung

1. 3__ on right ____2___ on left because the left only has 2 lobes (because the heart is larger on the left side)

iii. Segmental/tertiary bronchi

iv. Etc…

v. Bronchioles

1. Smaller than 1mm diameter

vi. Terminal bronchioles

1. Smaller than 0.5 mm_ diameter

i. ***Changes that occur with progression into the tree

1. Cartilage rings become plates and eventually are replaced with ______

2. Epithelium changes from pseudostratified columnar to __ columnar epithelium_ and finally to _____________

3. Increase in ______________

i. ***Changes that occur with progression into the tree

1. Cartilage rings become plates and eventually are replaced with __smooth muscle_

2. Epithelium changes from pseudostratified columnar to __ columnar epithelium_ and finally to __ simple cuboidal epithelium_

3. Increase in smooth muscle

i. Respiratory bronchioles – this is where smooth muscle stops; made of simple squamous epithelium; carries air into an _________

ii. Alveolar ducts – what connects the __________ to the ______ and carries air into the _____

iii. Alveolar sacs – cluster of alveoli; when we breathe, they ____________ (similar to a balloon);

iv. Alveolus (alveoli) –are surrounded by ______

v. The respiratory membrane – what the gas has to ____ during the e_______; also simple squamous epithelium; makes it easy to _________

1. Type 1 cells (majority of an alveolar wall)

a. Tissue type – simple squamous epithelium

b. Function – ______________

2. Type 2 cells –

a. Tissue type - simple cuboidal epithelium

b. Function – ____________, which keeps everything moist while decreasing surface tension (which would make inflation very difficult if they didnt), allowing everything to expand and deflate smoothly

3. A_____________connect adjacent alveoli

4. Alveolar macrophages – looking for ________________

i. Respiratory bronchioles – this is where smooth muscle stops; made of simple squamous epithelium; carries air into an alveolar duct

ii. Alveolar ducts – what connects the resp bronchioles to the alveoli and carries air into the alveoli

iii. Alveolar sacs – cluster of alveoli; when we breath, they expand and deflate (similar to a balloon);

iv. Alveolus (alveoli) –are surrounded by capillaries

v. The respiratory membrane – what the gas has to cross during the exchange of gases; also simple squamous epithelium; makes it easy to exchange gases

1. Type 1 cells (majority of an alveolar wall)

a. Tissue type – simple squamous epithelium

b. Function – makes diffusion of gases efficient

2. Type 2 cells –

a. Tissue type - simple cuboidal epithelium

b. Function – secretion of surfactant, which keeps everything moist while decreasing surface tension (which would make inflation very difficult if they didnt), allowing everything to expand and deflate smoothly

3. Alveolar pores connect adjacent alveoli

4. Alveolar macrophages – looking for things that make it into the lungs

1. Pleurae

a. Parietal pleura –

b. Visceral pleura –

c. Pleural cavity and pleural fluid –

1. Pleurae

a. Parietal pleura – inner layer that lies on the surface of the lung

b. Visceral pleura – lies against the chest wall

c. Pleural cavity and pleural fluid – place in between the pleurae; filled with pleural fluid, which acts as a lubricant

Pressures and resulting air movement in the thoracic cavity--

1. Pressures involved

a. Atmospheric pressure – the pressure of the atmosphere (at sea level = _________)

i. Lower atmosphere pressing down on you the ______ that you go

b. Intrapulmonary pressure – pressure -________

i. ___________ with each breath

ii. At the start and end of each inhale and exhale, the intrapulmonary pressure is equal to ________________

c. Intrapleural pressure – pressure in _________________________

i. ALWAYS ____________________________

1. This is due to two factors that create a slight vacuum effect:

a. _________

b. _____________

d. *Transpulmonary pressure – difference between i___________________

ii. This determines the ____________

Pressures and resulting air movement in the thoracic cavity--

1. Pressures involved

a. Atmospheric pressure – the pressure of the atmosphere (at sea level = 760 mmHg)

i. Lower atmosphere pressing down on you the higher that you go

b. Intrapulmonary pressure – pressure inside your lungs

i. ____rises___ and falls___ with each breath

ii. At the start and end of each inhale and exhale, the intrapulmonary pressure is equal to atmospheric pressure

c. Intrapleural pressure – pressure in between the visceral and parietal pleura

i. ALWAYS just slightly less that intrapulmonary pressure __

1. This is due to two factors that create a slight vacuum effect:

a. Recoil ability of lungs

b. Surface tension

d. *Transpulmonary pressure – difference between intrapulmonary and intrapleural pressure

i. Found by ___Intrapleural – intrapulmonary pressure _______

ii. This determined the size of the lungs

1.     Disorders

a.     Atelectasis –

b.    Pneumothorax –

1. Disorders

a. Atelectasis – collapsed lung

b. Pneumothorax – hole in the wall of the chest that causes atelectasis – transpulmonary pressure goes away bc both intrapulmonary and intrapleural pressure are now both equal to atmospheric pressure

Boyles Law:

as volume ______ pressure ______ and vice versa

 as volume ___increases__ pressure __decreases__ and vice versa

1. Pressure volume relationships

a. Boyles law:

i. More importantly, as volume _______ pressure ________ and vice versa

b. Differences in pressure

i. When there is a difference in 2 pressures and an available pathway then there will be ____________

1. Pressure volume relationships

a. Boyles law:

i. More importantly, as volume increases pressure ___decreases__ and vice versa

b. Differences in pressure

i. When there is a difference in 2 pressures and an available pathway then there will be movement

Steps of Inspiration

1. Diaphragm _____ and moves ___________

2. External intercostal muscles ______, and the ribs move ____ and ______.

3. The volume of the _______________increases and __________________ decreases

4. The decreased pressure pulls and ___________ the lungs _________

5. This causes the volume of the intrapulmonary space to __________.

6. The increase in volume causes intrapulmonary pressure to _________

7. Intrapulmonary pressure becomes lower than _____________(___ mmHg).

8. Air rushes into the lungs until _____________________

Steps of Inspiration

1. Diaphragm contracts and moves inferiorly (downward).

2. External intercostal muscles contract, and the ribs move up and outward.

3. The volume of the intrapleural space increases and Intrapleural pressure decreases

4. The decreased pressure pulls and stretches the lungs outward.

5. This causes the volume of the intrapulmonary space to increase.

6. The increase in volume causes intrapulmonary pressure to decrease.

7. Intrapulmonary pressure becomes lower than atmospheric pressure (760 mmHg).

8. Air rushes into the lungs until equilibrium is reached.

Steps of Expiration

1. Diaphragm _____ and moves _______.

2. External intercostal muscles _____, making the ribs move _____ and ______.

3. The volume of the intrapleural space ___________.

4. This causes intrapleural pressure to ___________

5. The lungs recoil and _______to a _______ size.

6. This causes the volume of the intrapulmonary space to __________.

7. This causes intrapulmonary pressure to ____________.

8. Intrapulmonary pressure now is __________ atmospheric pressure.

9. Air rushes out of lungs until intrapulmonary pressure is ______ as atmospheric pressure again (_________).

Steps of Expiration

1. Diaphragm relaxes and moves upward.

2. External intercostal muscles relax, making the ribs move inward and downward.

3. The volume of the intrapleural space decreases.

4. This causes intrapleural pressure to increase

5. The lungs recoil and pull back to a smaller size.

6. This causes the volume of the intrapulmonary space to decrease.

7. This causes intrapulmonary pressure to increase.

8. Intrapulmonary pressure now is above atmospheric pressure.

9. Air rushes out of lungs until intrapulmonary pressure is the same as atmospheric pressure again (equilibrium).

a. Forced expiration

i. Muscles involved?

1. Contracts ______ and ______

ii. This is the only time expiration is an active process*

b. Lung compliance

i. Ability of ___________- anything that messes with this affects your _________

a. Forced expiration

i. Muscles involved?

1. Contracts Internal intercostals and abdominals

ii. This is the only time expiration is an active process*

b. Lung compliance

i. Ability of lungs to expand- anything that messes with this affects your breathing

c. Disorders

i. Asthma – what happens when the _____________, resulting in a __________(a smaller place for air to move through)

ii. Infant respiratory distress syndrome (IRDS)

____________________________

c. Disorders

i. Asthma – what happens when the walls of the bronchioles become thicker, resulting in a smaller lumen (a smaller place for air to move through)

ii. Infant respiratory distress syndrome (IRDS)

1. Lungs are one of the last things developed; in babies that are born early, the type 2 cells (which release surfactant) aren’t developed and they don’t secrete surfactant, which means the lungs have to fight surface tension to inflate

2. ___Premature babies_ are most at risk

Lung volumes:

1. Measured using a _______

2. Respiratory volumes

a. Tidal volume (TV) – normal quiet inhale/exhale (about ______)

b. Inspiratory reserve volume (IRV) – air that you can forcefully inhale after a normal tidal inhale (about ________)

c. Expiratory reserve volume (ERV) – air that you can forcefully exhale after a normal tidal exhale (about __________)

d. Residual volume (RV) – air that remains in your lungs always, even after a forceful exhale

Lung volumes:

1. Measured using a spirograph__

2. Respiratory volumes

a. Tidal volume (TV) – normal quiet inhale/exhale (about 500 mL)

b. Inspiratory reserve volume (IRV) – air that you can forcefully inhale after a normal tidal inhale (about 3100ml)

c. Expiratory reserve volume (ERV) – air that you can forcefully exhale after a normal tidal exhale (about 1200 mL)

d. Residual volume (RV) – air that remains in your lungs always, even after a forceful exhale

Sticky Note:

1. Respiratory capacities

a. Inspiratory capacity (IC) – tidal vol + IRV

b. Functional residual capacity (FRC) – ERV + RV

c. Vital capacity (VC) – all of the air that you could possibly move – IRV + VC + ERV

d. Total lung capacity (TLC) – TV + IRV + ERV + RV

2. Dead space - the vol of the __________ (about 1 mL per pound of body weight) it is everything that takes up mass, but isn’t part of the ____________

1. Respiratory capacities

a. Inspiratory capacity (IC) – tidal vol + IRV

b. Functional residual capacity (FRC) – ERV + RV

c. Vital capacity (VC) – all of the air that you could possibly move – IRV + VC + ERV

d. Total lung capacity (TLC) – TV + IRV + ERV + RV

2. Dead space - the vol of the conducting zone (about 1 mL per pound of body weight) conducting zone is everything that takes up mass, but isn’t part of the respiratory zone

 

Sticky Note:

1.     Alveolar ventilation

a.     Minute ventilation – how much air is moved per breath

                                               i.     MV = BR x TV (Sound familiar? It should! Think “Cardiac Output)

b.    Alveolar ventilation rate (AVR) – how much of  the air that you breathe in gets to the parts of the lung that are involved in gas exchange

                                               i.     Better than minute ventilation

1.     AVR = BR x (TV – dead space)

1. What is partial pressure - represents the ______________of a gas to the ___________, which is the sum of all partial pressures.

individual contribution

total pressure

1. Dalton’s Law

a. Total pressure of a mix of gasses is equal to _______________

b. At higher altitudes, pressure is ___ therefore there is _______

1. Dalton’s Law

a. Total pressure of a mix of gasses is ___equal to the pressure of the whole mixture___

b. At higher altitudes, pressure is lower therefore there is less oxygen

c. % of a gas/contribution x total pressure is equal to the partial pressure

atmospheric pressure at sea level=

760mmHg

Composition of air IN ORDER

a. N2

b. O2

c. H2O

d. CO2

External Respiration

1. Movement of gas between __________ ______

a. Oxygen – has a steeper____________

b. Carbon dioxide – more ____________

2. Partial pressure gradients and solubility

a. Oxygen has a steeper ___________

b. Equal amounts of oxygen and carbon dioxide are exchanged due ___to the fact that we can ______(2 reasons) ______

1. Movement of gas between ___the lungs and the blood ______

a. Oxygen – has a steeper partial pressure gradient

b. Carbon dioxide – more soluble

2. Partial pressure gradients and solubility

a. Oxygen has a much steeper ___ has a steeper partial pressure gradient __

b. Equal amounts of oxygen and carbon dioxide are exchanged due ___to the fact that we can pack a lot more CO2 into fluid than we can oxygen, and O2 has the steeper partial pressure gradient__

Thickness of respiratory membrane – ____________thick, meaning gas can diffuse _______________

2 layers of squamous epithelium

easier and more efficiently

1. Ventilation perfusion coupling

i. Ventilation is the_________________; perfusion = _____________________

ii. We want these to match

b. Role of oxygen – changes the ______________ to allow more or less blood into the capillary

c. Role of carbon dioxide – changes the _______________

i. Less ventilation than perfusion →oxygen autoregulates the __________→pulmonary arterioles serving these alveoli _________→ match of vent and perfusion

ii. More ventilation than perfusion → oxygen autoregulates the ___________ → pulmonary arterioles serving these alveoli _______ → match

1. Ventilation perfusion coupling

i. Ventilation is the movement of air in and out of the alveoli; perfusion = how much blood is moving through a capillary

ii. We want these to match

b. Role of oxygen – changes the diameter of the arteriole to allow more or less blood into the capillary

c. Role of carbon dioxide – changes the diameter of the bronchiole

i. Less ventilation than perfusion  oxygen autoregulates the arteriolar diameter  pulmonary arterioles serving these alveoli constrict match of vent and perfusion

ii. More ventilation than perfusion  oxygen autoregulates the arteriolar diameter  pulmonary arterioles serving these alveoli dilate  match

Internal respiration:

1.     Movement of gases between _________________ & ___________

Internal respiration:

1. Movement of gases between ____the capillaries and the tissue cells of the body____

Sticky Note!!

Tying internal respiration, external respiration, and partial pressures together: (you DO need to know these numbers)

1. Oxygen partial pressures (pO2 )

a. High (100-105mmHg)

i. Locations

1. Lungs/alveoli

2. Pulmonary veins

3. Systemic arteries

b. Low (40 mmHg)

i. Location

1. Tissues

2. Pulmonary arteries

3. Systemic veins

2. Carbon dioxide partial pressures (pCO2)

a. High (45 mmHg)

i. Locations

1. Tissues

2. Pulmonary Arteries

3. Systemic veins

b. Low

i. Locations

1. Lungs/alveoli

2. Pulmonary veins

3. Systemic arteries

1.     Gas movement at lungs (include partial pressures)

• See document

Oxygen Transport:

i. Each hemoglobin can hold _________

1. When carrying 4 oxygens = _____saturated (3=___, 2=__, 1=__)

ii. Binding of an oxygen causes _________ which results in hemoglobin ________(it now likes o2 more than it did before), making it easier for ____________(happens every time O2 binds with the hemoglobin) __

1. If H+ is low, and O2 is high, then more ___________, and there will be more ________ (and the opposite is true)

i. Each hemoglobin can hold 4 oxygens

1. When carrying 4 oxygens = 100% saturated (3=75, 2=50, 1=25)

ii. Binding of an oxygen causes __hydrogen ion to fall off_ which results in hemoglobin changing shape (it now likes o2 more than it did before), making it easier for another o2 to attach (happens every time O2 binds with the hemoglobin) __

1. If H+ is low, and O2 is high, then more oxygen will bind to the hemoglobin, and there will be more H+ around (and the opposite is true)

a. Factors influencing saturation

i. pO2

1. partial pressure of oxygen

2. ↑pO2 → __saturation (when oxygen is up, saturation of hemoglobin goes up)

ii. pCO2

1. ↑pCO2 → saturation (because carbon dioxide binds to hemoglobin than oxygen – it will knock the _____ off to bind to hemoglobin)

iii. pH

• ↓pH (which is an increase in H+ concentration) → ___saturation

o If there is more H+, it will bind to hemoglobin, knocking the oxygen off

o Low pH (acidity) also ____________

iv. Temperature

1. ↑temperature→ saturation (because high temp ___________, meaning the hemoglobin now cant carry oxygen as well)

a. Factors influencing saturation

i. pO2

1. partial pressure of oxygen

2. ↑pO2 → ↑saturation (when oxygen is up, saturation of hemoglobin goes up)

ii. pCO2

1. ↑pCO2 → ↓saturation (because carbon dioxide binds to hemoglobin easier than oxygen – it will knock the O2 off to bind to hemoglobin)

iii. pH

• ↓pH (which is an increase in H+ concentration) → ↓saturation

o If there is more H+, it will bind to hemoglobin, knocking the oxygen off

o Low pH (acidity) also denatures protein

iv. Temperature

1. ↑temperature→ ↓saturation (because high temp denatures protein, meaning the hemoglobin now cant carry oxygen as well)

****Tissues with high metabolism (high oxygen demand), for example exercising

- When you use your leg muscles a lot: (decrease in oxygen, increase in CO2, high lactic acid → decrease in pH, increase in temp) → all cause____________

o Why would we want low saturation where we need it the most?

• __________________________________________________________________

decrease in saturation

Because we don’t want the hemoglobin to hold onto the oxygen, we want the oxygen to fall off the hemoglobin and be diffused into the muscle and used SO REDUCING SATURATION MAKES IT EASIER FOR O2 TO MOVE INTO THE TISSUE

Saturation

a. In the lungs:

i. __pO2 - Theres a lot of oxygen bc we’re constantly breathing more in

ii. __pCO2 – we’re constantly breathing it out

iii. __pH – the inside of the lungs is slightly alkaline

iv. __temp – because the lungs are outside the body

1. ALL OF THESE THINGS CAUSE? ___________ – we want this. The lungs create an environment that makes hemoglobin really like ________

b. REMEMBER- some, not much, oxygen is _______________

a. In the lungs:

i. ↑pO2 - Theres a lot of oxygen bc we’re constantly breathing more in

ii. ↓pCO2 – we’re constantly breathing it out

iii. ↑pH – the inside of the lungs is slightly alkaline

iv. ↓temp – because the lungs are outside the body

1. ALL OF THESE THINGS CAUSE? Increased saturation – we want this. The lungs create an environment that makes hemoglobin really like oxygen.

b. REMEMBER- some, not much, oxygen is dissolved in the plasma

Disorders:

a. Hypoxia – low oxygen

i. Anemic hypoxia -

ii. Ischemic hypoxia -

iii. Histotoxic hypoxia -

1. Tissue can’t use O2 for example cyanide poisoning - stops a part of cell respiration so ATP is not produced

iv. Hypoxemic hypoxia -

v. Carbon monoxide poisoning -

a. Hypoxia – low oxygen

i. Anemic hypoxia - not enough oxygen bc you have some sort of iron deficiency

ii. Ischemic hypoxia - ischemia = reduced blood flow – not good blood flow= disrupts o2 transport

iii. Histotoxic hypoxia - some poisons affect the tissues’ ability to use oxygen.

1. Tissue can’t use O2 for example cyanide poisoning - stops a part of cell respiration so ATP is not produced

iv. Hypoxemic hypoxia - suffocation, not enough oxygen available to breathe

v. Carbon monoxide poisoning - (CO) = carbon monoxide. CO likes hemoglobin more than any other gas – it will bind with hemoglobin and prevent O2 from binding. It is pretty much irreversible – when CO binds to hemoglobin, an O2 cannot bind

Carbon dioxide transport:

- CO2 is very soluble

1. Dissolved in plasma (7-10%)

2. Bound to ____________(20%ish)

a. Globin – O2 binds to the

_________ CO2 binds to the _________ (globin)

b. When CO2 is bound to the globin, we call it HbCO2, carbaminohemoglobin

3. As _______________ in plasma (70%)

Carbon dioxide transport:

- CO2 is very soluble

1. Dissolved in plasma (7-10%)

2. Bound to hemoglobin (20%ish)

a. Globin – O2 binds to the heme group, CO2 binds to the protein (globin)

b. When CO2 is bound to the globin, we can it HbCO2, carbaminohemoglobin

3. As bicarbonate ions in plasma (70%)

How is most CO2 carried in the blood?

What are the products of CO2 and water?

- As bicarbonate ion

- Bicarbonate ion and H+

1. Notice that H+ is produced for each CO2 that follows the bicarbonate pathway

a. As CO2 increases, therefore _?_pH

b. Shallow breathing

a. If someone is breathing shallowly/slowly, they are breathing ____, which leads to _?_pCO2

b. _?_ pCO2 → ↑H+ (_?_pH)

c. Rapid breathing

a. If someone is breathing more rapidly or more deeply, they are breathing more

b. _?_ pCO2 → _?_H+ (_?_pH)

1. Notice that H+ is produced for each CO2 that follows the bicarbonate pathway

a. As CO2 increases, therefore ↓pH

a. EXAM QTN: Just because someones pH is low DOES NOT MEAN that you know/can assume anything about their CO2 – many factors influence pH, not just CO2

b. Shallow breathing

a. If someone is breathing shallowly/slowly, they are breathing less, which leads to an increased build up of CO2 in the body(↑pCO2)

b. ↑ pCO2 → ↑H+ (↓pH)

c. Rapid breathing

a. If someone is breathing more rapidly or more deeply, they are breathing more

b. ↓ pCO2 → ↓H+ (↑pH)

a. EXAM QTN: Just because someones pH is low DOES NOT MEAN that you _____________________

know/can assume anything about their CO2 – many factors influence pH, not just CO2

Control of respiration by neural mechanisms:

1. Medulla respiratory centers

a. Ventral respiratory group (VRG) – responsible for ________________by initiating inspiration and expiration – it does this by ________________ at a regular rate without any input

b. Dorsal respiratory group (DRG) – ______________ set by the VRG, telling it to ___________, or __________(depolarize less quickly)

2. Pontine respiratory centers (in the ____)

a. Pontine respiratory group (PRG) –

i. _______function________

ii. Times your breathing based on ____________ – (ex. Singing and breathing at specific spots, taking a breath at the end of a sentence in a speech)

Control of respiration by neural mechanisms:

1. Medulla respiratory centers

a. Ventral respiratory group (VRG) – responsible for setting your respiration rate by initiating inspiration and expiration – it does this by spontaneously depolarizing at a regular rate without any input

b. Dorsal respiratory group (DRG) – modifies the rate set by the VRG, telling it to depolarize (speed up) more quickly, or slow down (depolarize less quickly)

2. Pontine respiratory centers (in the pons)

a. Pontine respiratory group (PRG) –

i. Smooths the transition between an inhale and an exhale

ii. Times your breathing based on certain activities – (ex. Singing and breathing at specific spots, taking a breath at the end of a sentence in a speech)

Factors that influence rate and depth of respiration:

1. Important chemical factors

a. _____________

i. ___ is the most important chemical factor that influences our breathing depth and rate

ii. __ is also very important in influencing breathing depth and rate

iii. Hypercapnia – elevated _______ (hypocapnia = the opposite)

b. Less important: ___

i. Most of the time doesn’t play any role in out breathing but actually _function_________

Factors that influence rate and depth of respiration:

1. Important chemical factors

a. CO2, pH

i. CO2 is the most important chemical factor that influences our breathing depth and rate

ii. pH is also very important in influencing breathing depth and rate

iii. Hypercapnia – elevated CO2 (hypocapnia = the opposite)

b. Less important: O2

i. Most of the time doesn’t play any role in out breathing but actually sensitizes some of the receptors to CO2

1. Central chemoreceptors – most important

a. Location – front portion of the _____ (in the brainstem)

b. Detect H+ (pH) – by sampling the ________

c. BBB – separates the brain from the blood

i. Central chemoreceptors sample the CSF for its __, then send a signal to the brain (the DRG), which then tells the VRG to speed or slow breathing

ii. cannot cross the BBB bc it has a positive charge, but ____ can

iii. AND, CSF is made of water, AND the ependymal cells that make the CSF, also make ______enzyme_____

iv. So when ___ crosses, it reacts with H2O (very quickly bc of the carbonic anhydrase) and creates H2CO3, which dissociates into HCO3- and H+ (which the central chemoreceptors CAN detect)

1. Central chemoreceptors – most important

a. Location – front portion of the medulla (in the brainstem)

b. Detect H+ (pH) – by sampling the cerebrospinal fluid

c. BBB – separates the brain from the blood (things that are very very small and do not have a charge can cross the BBB)

i. Central chemoreceptors sample the CSF for its pH, then send a signal to the brain (the DRG), which then tells the VRG to speed or slow breathing

ii. H+ cannot cross the BBB bc it has a positive charge, but CO2 can

iii. AND, CSF is made of water, AND the ependymal cells that make the CSF, also make carbonic anhydrase

iv. So when CO2 crosses, it reacts with H2O (very quickly bc of the carbonic anhydrase) and creates H2CO3, which dissociates into HCO3- and H+ (which the central chemoreceptors CAN detect)

v. Example if pH is low (lots of H+) - chemoreceptors then tell the ___ that pH is low, the DRG tells the central respiratory group the same thing, and the V____ responds by breathing ______ removing CO2 with every breath, making ph more alkaline)

d. Hyperventilation*

i. CO2 is down (very low), H+ is low, and it tries to tell the central chemoreceptors that pH is high, but there may be a glitch and someone having a hyperventilative attack, they cant slow down

ii. The reason that you give them a paper bag is because _______________________

v. Example if pH is low (lots of H+) - chemoreceptors then tell the DRG that pH is low, the DRG tells the central respiratory group the same thing, and the VRG responds by breathing faster (removing CO2 with every breath, making ph more alkaline)

d. Hyperventilation*

i. CO2 is down (very low), H+ is low, and it tries to tell the central chemoreceptors that pH is high, but there may be a glitch and someone having a hyperventilative attack, they cant slow down

ii. The reason that you give them a paper bag is because then, they breathe back in the CO2 that they’ve been releasing, bringing CO2 levels back up in the blood

1. Peripheral chemoreceptors –

i. These sample the ________

b. Location - same location as the baroreceptors (in the ____________________________

c. Detect _______3_________

iv. Minor role of O2 is to ______________ to CO2 (we need oxygen for these receptors to detect CO2)

1. Example Scenario – long run

a. Buildup of lactic acid → ↓pH → peripheral chemoreceptors detect low pH (they can detect changes in pH from any source because they sample the blood directly) → send signals to DRG → VRG → ↑ respiratory rate → ↓pCO2 → ↓H+ (↑pH)

i. Even though CO2 levels weren’t the problem (it was decreased pH caused by lactic acid), we can adjust pH by ______________

1. Peripheral chemoreceptors –

i. These sample the blood directly

b. Location - same location as the baroreceptors (in the carotid bodies of the carotid sinuses, and the arch of the aorta (in the aortic bodies)

c. Detect CO2, H+ (pH), O2

i. CO2 dissolved in the plasma

ii. Any pH at all

iii. And somewhat sensitive to O2

iv. Minor role of O2 is to sensitize receptors to CO2 (we need oxygen for these receptors to detect CO2)

1. Example Scenario – long run

a. Buildup of lactic acid → ↓pH → peripheral chemoreceptors detect low pH (they can detect changes in pH from any source because they sample the blood directly) → send signals to DRG → VRG → ↑ respiratory rate → ↓pCO2 → ↓H+ (↑pH)

i. Even though CO2 levels weren’t the problem (it was decreased pH caused by lactic acid), we can adjust pH by using CO2

a. Hypoxic drive –

i. _________ becomes the primary stimulus for breathing

ii. When ___oxygen___ is below ______mmHg in arterial blood (they should be about 95-100mmHg) ____

1. Can happen in a patient with COPD (prolonged difficulty breathing → very high CO2 levels and pH is very low)

iii. Prolonged elevated CO2 results in receptors being ______________ to CO2 or pH, due to oxygen starvation and prolonged elevated CO2, meaning that oxygen can then _________________________________

iv. What should be done and what happens if too much oxygen is given?

____________________________________________

a. Hypoxic drive –

i. ___oxygen___ becomes the primary stimulus for breathing

ii. When ___oxygen___ is below ____60 mmHg in arterial blood (they should be about 95-100mmHg) ____

1. Can happen in a patient with COPD (prolonged difficulty breathing → very high CO2 levels and pH is very low)

iii. Prolonged elevated CO2 results in receptors being numb/nonresponsive to CO2 or pH, due to oxygen starvation and prolonged elevated CO2, meaning that oxygen can then stimulate the peripheral chemoreceptors to tell you to breathe

iv. What should be done and what happens if too much oxygen is given?

1. If someone is having this much trouble breathing, giving them oxygen back up to normal would remove the stimulus for the patient to breath – so you have to give them oxygen but cut it off so that their O2 mmHg levels stay below 60

1. Hypothalamic controls of breathing?

a. Limbic system

i. Emotions

ii. Pain or cold

1. Gasping – either can cause a gasping breath

1. Cortical control - ___________________

2. Proprioceptors – specialized nerve endings that detect the position of our body in space – if you ____ more than normal these proprioceptors send signals to the DRG → signals to the VRG → breathe ______

3. Irritant reflex – ______________________

4. Hering-Breuer reflex – __________ receptors on the surface of the lungs that detect inhalation, which when lungs are fully inflated, send inhibitory signals to the control resp group, preventing VRG to send any signals that would cause more inhalation

1. Cortical control

a. Voluntary breathing – where we choose when or how fast to breath

2. Proprioceptors – specialized nerve endings that detect the position of our body in space – if you move more than normal these proprioceptors send signals to the DRG  signals to the VRG  breathe faster

3. Irritant reflex – holding breath or coughing when around smoke, harsh chemicals, etc. – prevents damage to the lungs

4. Hering-Breuer reflex – stretch receptors on the surface of the lungs that detect inhalation, which when lungs are fully inflated, send inhibitory signals to the control resp group, preventing VRG to send any signals that would cause more inhalation

Why does breathing change during exercise? – all of this happened before CO2 starts to build up or pH starts to drop

(3 reasons)

Why does breathing change during exercise? – all of this happened before CO2 starts to build up or pH starts to drop

1. Psychological – you learn that every time I start exercising, I start breathing faster, so it becomes learned behavior

2. Cortical activation of skeletal muscle and respiratory centers – activation of conscious movement of skeletal muscles sends a signal to respiratory centers, saying “hey start breathing faster”

3. Proprioceptor input – detect when we are moving, and when we are moving signals are sent to our medulla oblongata

Disorders:

1. Chronic obstructive pulmonary disease (COPD) - characterized by an irreversible decrease in the __________________

a. A class of diseases

i. Emphysema - Enlargement of alveoli

2. Destruction of alveolar walls

3. Loss of elasticity

4. Collapse of bronchioles

a. Traps air

b. Barrel chest - ?

ii. Chronic bronchitis

1. Inhaled irritants – leads to chronic production of excess _______, the mucosae become inflamed and fibrous and obstruct the airways – this impairs lung ventilation and gas exchange

b. More than 80% of diagnosed have a _______________

c. Dyspnea - difficult or labored breathing often referred to as “air hunger,” gets progressively worse.

d. Hypoventilation - insufficient ventilation in relation to metabolic needs, causing them to retain CO2

e. Two common “types”

i. Pink puffers - Exertion of breathing leads to ___________________

ii. Blue bloaters - (Commonly have a stocky build) Unable to maintain ____________________________

ability to force air out the lungs

barrel - the bronchioles open during inspiration but collapse during expiration, trapping huge volumes of air in the alveoli. This leads to development of a permanently expanded “barrel chest” and flattens the diaphragm, reducing ventilation efficiency.

mucus

history of smoking

i. Pink puffers - Exertion of breathing leads to weight loss but adequate blood gas levels

ii. Blue bloaters - (Commonly have a stocky build) Unable to maintain blood gas levels and it causes them to be hypoxic → obviously cyanotic

1. Tuberculosis (TB)

a. Bacterial infection by Mycobacterium tuberculosis - symptoms include fever, night sweats, weight loss, racking cough, and coughing up blood.

i. 1/3 people infected but most __________

1. Because, a massive inflammatory and immune response usually contains the primary infection in fibrous, or calcified, nodules (tubercles) in the lungs

never develop the disease

What kind of lung cancer can affect the hormones?

c. Small cell carcinoma

i. 20%

ii. Originates in main bronchi and grows in mediastinum

iii. Very metastatic

iv. Many produce hormones like ADH

Cystic fibrosis is caused by?

b. Cl- channel mutation - causes the protein to misfold and get degraded before it reaches the cell membrane

i. Water isn’t moved properly

ii. Leads to mucous buildup