Module 17: Respiratory System Flashcards
List the functions of the respiratory system (6)
- provides for gas exchange
- helps regulate blood pH
- contains smell receptors
- filters incoming air
- produces vocal sounds
- excretes water and heat
Name the four respiratory processes (4)
- pulmonary ventilation
- external respiration
- transport of respiratory gases to the tissues
- internal respiration
moving air into and out of the lungs is defined as
pulmonary ventilation
exchange of gases at the alveoli of the lungs is defined as
external respiration
exchange of gases between blood and tissue is defined as
internal respiration
part of the respiratory system (zone) that brings air into or out of the lung is defined as
conducting zone
the part of the respiratory system (zone) where gas exchange takes place
respiratory zone
what structures make up the conducting zone?
- nose
- pharynx
- larynx
- trachea
- bronchi
- bronchioles
- terminal bronchioles
what is the function of the conducting zone?
to filter, warm, moisten and conduct air to the lungs
what structures make up the respiratory zone?
- respiratory bronchioles
- alveolar ducts
- alveolar sacs
- alveoli
the respiratory tract is also divided into _____ and _____ portions
upper, lower
upper respiratory tract includes:
- nasal cavity
- oral cavity
- pharynx
- larynx (views differ but for this text know its classified in the upper respiratory tract)
lower respiratory tract includes:
- trachea
- ALL components of the lungs
the upper respiratory tract is full of _____ ______
endogenous (normal) flora, (full of microorganisms)
the lower respiratory tract should be ______
sterile
sputum:
abnormal, thick mucus (spit mixed with respiratory secretions)
the _____ is often cultured if a physician suspects pneumonia.
sputum
Function of nose and paranasal sinuses
Moisturize, warm, & filter
Serves as a passageway for air and food, is a resonating chamber for sound, and house the tonsils
Pharynx
3 zones of pharynx
Nasopharynx
Oropharynx
Laryngopharynx
Lies between the internal mates and has sourest respiratory function
• Eustachian tubes
• houses the pharyngeal tonsils(adenoids)
Nasopharynx
Lies between the moth with both reparatory and digestive functions
•houses the palatine tonsils and the lingual tonsils
Oropharynx
Lies inferior to the oropharynx and opens into the larynx and esophagus
• respiratory and digestive functions
Laryngopharynx
Floating, u-shaped bone in anterior neck
Hyoid bone
“Sorting paddle” that detects and responds to material entering the oropharynx
Epiglottis
Opening of the larynx
Glottis
How is sound produced
By vibrations as air passes the vocal chords
- Connects the laryngopharynx with the trachea.
Larynx
The greater the _____ the louder the sound
Pressure
Single cartilage
Thyroid
Epiglottis
Cricoid
Paired cartilage
Arytenoid
Corniculation & cuneiform
Forms the anterior surface of the larynx
Thyroid
Leaf shaped piece of byline cartilage that closes over the larynx when food or liquids are swallowed. Also allows gases, O2, through the larynx into the trachea
Epiglottis
A ring of hyaline cartilage that forms the inferior portion of the larynx
Cricoid
Influences change in position and tension of the vocal folds
Arytenoid
Support the vocal folds and the epiglottis
Corniculate & cuneiform
- A semi-rigid passageway for air that’s about 12 cm long.
- 16-20 c-shaped rings of cartilage
- posterior surface shared with esophagus
Trachea
Pathway of air
- Outside worlds
- Mouth or nose
- Pharynx
- Larynx
- Trachea
- Left or Right primary Broncos
- Secondary bronchus
- Tertiary bronchus
- Bronchioles
- Terminal bronchioles
- Respiratory bronchioles
- Alveoli
- Bloodstream
Bronchioles end in the basic unit of the lung, the _____
Lobule
Each lobule contains…(4)
Lymph vessel
Arteriole
Venule
Terminal bronchiole
Grape-like clusters at the end of the respiratory bronchioles where has exchange occurs
Alveoli
Which primary bronchus extends more vertically, is wider, and shorter…an aspirated object is more likely to lodge in this side.
Right
An internal ridge where the trachea divides into the right and left bronchi and is used as a landmark when performing a bronchoscopy or visual examination of the bronchi. FYI: it’s a very sensitive area for triggering the cough reflex
Carina (Latin: boat prow)
How many lives in the right lung
3
How many loves in the left lung
2
FYI: there’s 1 secondary bronchus for each love of the lung
🤓
Apex
Superior part of lung
Base
Inferior part of lung
An opening on the medial surface of each lung that lets the primary bronchi, blood vessels, lymph vessels, and nerves enter
Hilum
Visceral pleura
Adheres to lung
Parietal pleura
Adheres to chest wall
Pleural fluid
- reduces frictions
- allows easy movement as the lungs expand and contract
- allows the visceral and parietal pleura because of the surface tension it creates
What is pleurisy
Membrane becomes inflamed
What’s pleural effusion
Excess fluid in the pleural cavity
- Muscle that forms the floor of the thoracic cavity.
- most important muscle to power breathing
- responsible for ~75% of the air that enters the lungs during quiet breathing
The diaphragm
Make up the intermediate layer of the intercostal space. Help decrease the size of the thoracic cavity during forced exhalation.
Internal intercostal muscles
Distributed over the superior surface of diaphragm and causes contraction of the diaphragm muscles
Phrenic nerve
Where does the phrenic nerve originate from
C3-5
Sympathetic
Dilation of bronchial smooth muscle
Cells & Nerves:
• preganglionic cells bodies in intermediate horn of T1-T4 spinal cord
• postganglionic cell bodies in sympathetic chain ganglia
• nerves form pulmonary plexus in hilum of lung
Parasympathetic
- Innervation via CN X (vagus nerve)
- release ACH
- causes mucus secretion and construction of bronchial smooth muscle
- movement of air into the lungs
- an active process and requires muscle action
Inspiration/Inhalation
- movement of air out of the lungs
- usually a passive process due to quiet breathing due to elasticity of lung
- active muscle help during vigorous exercise or certain disease conditions causing difficulty (COPD)
Expiration/Exhalation
The process of gas exchange in the body
Respiration
Apply Boyle’s Law to inspiration
Contraction of diaphragm and external intercostals =
⬆️ Volume
⬇️ Pressure
Accessory muscles (3)
- Sternocleidomastoid: elevates sternum
- scalene muscles
- pectoral is minor: elevate ribs
Muscles produce two movements in chest
- “pump handle” action of sternum
- “bucket handle” action of ribs
Apply Boyle’s Law to exhalation
Elastic recoil of chest wall & lungs =
⬇️ Volume
⬆️ Pressure
Apply Boyle’s Law to forced exhalation
Abdominal muscles and internal intercostals contract further =
⬇️⬇️⬇️⬇️ Volume
⬆️⬆️⬆️⬆️ Pressure
What measures the volume of air exchange during breathing and the respiratory rate
Spirometer
Record of spirometer
Spirogram
Volume of air inspired or expired during normal quiet breathing
Tidal Volume (Vt)
All of the air that you can breathe in form the top of tidal volume (during a very deep inhalation)
Inspiration Reserve Volume
All of the air that you can breath out from the bottom of tidal volume during a forced exhalation
Exploratory Reserve Volume
Air still present in the lung tissue after maximal exhalation. It is what keeps the lungs open even after we have breathed out all that we can
Residual Volume
Combination of specific lung volumes
Respiratory capacities
The sum of tidal volume and inspiration reserve volume
Inspiratory capacity
The sun of residual volume and expiratory reserve volume
Functional residual capacity
The sum of inspiratory reserve volume, tidal volume, and expiratory reserve volume
Vital capacity
Sum of vital capacity and residual volume
Total lung capacity
Where does external respiration occur
The alveolar-capillary membrane
In order for a molecule of gas to pass from the alveolar space into the blood, it must cross these layers:
- Across the membrane and cytoplasm of the very thin type 1 alveolar cell
- Through the basement membrane of the type 1 alveolar cell
- Through the basement membrane of the endothelial cell
- Across the membrane and cytoplasm of the very thin endothelial cell lining the capillary
Process of external respiration
- Deoxygenated blood is carried from the heart to the lungs by the pulmonary arteries and arterioles
- Gas exchange takes place at the capillaries covering the alveoli
- Oxygenated blood is carried from the lungs to the heart by the pulmonary veins and venules
Where does internal respiration occur
Capillaries
Process of internal respiration
- O2 is delivered to the body’s tissues
- CO2 is picked up and carried back to the lungs for excretion
What has the highest Po2 (106mmHg) for internal respiration oxygen
Alveolar air
What has the lowest Po2 (40mmHg) for internal respiration oxygen
Tissue
________ picks up O2 where the concentration (partial pressure) is highest and releases O2 where it’s partial pressure is lowest
Hemoglobin
Most of the carbon dioxide is carried as __________________
Bicarbonate ion (HCO3-)
What has the highest Pco2 (45 mmHg) for internal respiration carbon dioxide
Tissue
What has the lowest pco2 for internal respiration carbon dioxide
Alveolar air
In the O2-hemoglobin saturation curve, the higher the PO2 the ____ oxygen is bound to Hb
More
Where is PO2 highest (97%)
Alveolar air and arterial blood
Where is Po2 the lowest (~or
Tissues
Do tissues need more or else O2 during exercise
More
True/False: actively working tissues generate acids as waste, highering the pH
False: it lowers the pH
What does pH have to do with the O2-hemoglobin saturation curve
A drop in pH shifts the curve to the right = more O2 to be released at the tissues
Normal blood pH
7.4
Higher PCO2 levels shifts the O2-Hb saturation curve to the _____ and _____ O2 is delivered to the tissues
Right, more
What happens in the O2-Hb Saturation Curve if it’s shifted to the Right
- less O2 bound at lung
- more O2 delivered at tissues
What happens when the O2-Hb Saturation Curve shifts to the left
- more O2 at lungs
- less O2 at tissues
Do higher temperatures shift the O2-Hb Saturation Curve to the right or left
Right
How does fever help deliverance of O2
When we’re sick and have a fever, more O2 is delivered to the tissues helping them fight infection
Fetal Hb has a ________ affinity for O2 than adult Hb
Higher
When PO2 is low, fetal Hb can carry up to ____ more O2 than maternal Hb
30%
4 things that affect O3-Hb Saturation Curve
- pH
- Effect of Pco2
- temperature
- pregnancy
What is the most important buffer system in human biology?
Carbonic acid-bicarbonate buffer system
Equation for carbonic acid-bicarbonate buffer system
H2O + CO2 H2CO3 H+ + HCO3
Does H+ ⬆️ or ⬇️ when pH is low. What happens?
⬆️ this pushes reaction to the left and more H2P and CO2 are made
Does H+ ⬆️ or ⬇️ when pH is high? What’s happens?
⬇️ this pushes the reaction to the right and more H+ are released
Function of medulla rhythmic its area
Control basic rhythm of respiration
Inspiratory center
- stimulate diaphragm by phrenic nerve
- stimulates external intercostals by intercostal nerves
Expiratory center
- inactive during quiet breathing
* stimulates internal intercostals and abdominal muscles to contract during forced exhalation
Limits duration of inspiration to prevent lungs from getting fully
Pneumotaxic center
Coordinates transition between inhalation and exhalation
Apneustic center
Emotions
Affect breathing
Hypercapnia, low O2, or acidosis
Stimulate more rapid breathing
Bronchial stretch receptors (Hering-Breuer reflex)
Sense overinflation, arrest breathing temporarily
Hypothalamus
Sense fever, increase breathing
Moderate pain
Increase breathing
Severe pain
Causes apnea–a temporary cessation of breathing
When do the lungs begin to develop in a fetus
4th week
When do lungs become highly vascular and respiratory bronchioles, alveolar ducts, and some primitive alveoli begin to develop in fetus
16-26 weeks
When do alveoli develop in fetus
26+ weeks
Fetal primary and secondary bronchi visible at
5th week
Fetal tertiary bronchi visible at
6th week
Fetal lives of lung evident at
End of 8th week
Earliest viable premature babies are
26 weeks down, 23 weeks to go
Alveoli must overcome _______ to inflate
Surface tension (the reason a glass doesn’t overflow over the brim when you pore water in it)
Surfactants
The reduce surface tension in water. One end likes grease, the other likes water
Ex. Detergents
______ is necessary to prevent the collapse of alveoli on exhalation
Surfactant
When is enough surfactant sufficient enough to permit survival of a premature infant
Produced at 26-28 weeks of gestation
Infant Respiratory Distress Syndrome (IRDS)
Failure to make sufficient surfactant at birth can lead to this
- 2/3 infants
Surfactants used for neonates
Exosurf (synthetic) Survanta (minced cow lung) Infasurf (calf lung) Curosurf (pig lung) Surfaxin (synthetic)
