The respiratory system consists of passageways that transport air to and from microscopic air sacs in the lungs called alveoli. At the alveoli, oxygen from the inhaled air diffuses into blood vessels and carbon dioxide from the blood diffuses out. This gas exchange is called external respiration. The respiratory and cardiovascular systems work together to deliver oxygen from the lungs to cells throughout the body and remove carbon dioxide from the cells back to the lungs in a continuous cycle. The upper respiratory tract conditions incoming air by warming, humidifying, and filtering it before it reaches the delicate alveoli in the lungs.
The content in the slide are solely depended upon the syllabus of Purbanchal University for third-semester students. This content of the respiratory system will be enough for B.Pharmacy students studying anatomy and physiology
Specialities in Birds respiratory system: Air sacs, specialized parabronchi , Unidirectional flow
Benifits of air sacs, Benefit of 2 respiratory cycles
Bird-like respiratory systems in dinosaurs
Rate of breathings in birds
The content in the slide are solely depended upon the syllabus of Purbanchal University for third-semester students. This content of the respiratory system will be enough for B.Pharmacy students studying anatomy and physiology
Specialities in Birds respiratory system: Air sacs, specialized parabronchi , Unidirectional flow
Benifits of air sacs, Benefit of 2 respiratory cycles
Bird-like respiratory systems in dinosaurs
Rate of breathings in birds
"Burning Man" How to survive in the desert and build a "LOVE"Olexandr Ovsianko
"How to create a city of 70 000 people to survive for 7 days. How to survive in the desert and build a "LOVE". What is Playa and MOOP. 10 Commandments of the new world. How to go and get satisfaction from unusual employment journey.
We begin a new format of Public Programs - Youth Tuesdays, at the event which will invite young architects and urbanists share their experiences and tell their interesting projects.
The first event under this format will be meeting with Olexandr Ovsianko - graduate CANactions School Studio # 2. 2015 Sasha had a chance to go to Burning Man to the United States, which has repeatedly talked enthusiastically CANactions for students in school. It's time to share it with the public.
Alexander tells about his impressions of participation in the world-famous festival, the temporary city in the desert, living in it and Ukrainian installation "LOVE", pictured above. We invite you to plunge into the mystery nevadskoyi desert night October 25 in CANactions.
Human respiratory system powerpoint presentationRitu Sharma
All living organisms guzzle food to produce energy for the consistent working of the body. This is precisely what we do through the method of respiration. Respiration is the natural process through which all the cells of living organisms acquire the energy to accomplish certain life processes that are crucial for existence. Glucose from the food that the animals ingest, gets fragmented down into simpler elements and energy is released. As respiration takes place in the cells of organisms, it is called cellular respiration
Respiration Process which involves taking in oxygen into the cells, using it for releasing energy by burning food and then eliminating the waste products like carbon dioxide and water from the body It is a catabolic process as the food is broken down into simpler form. In short, respiration is a biochemical activity taking place with in the protoplasm of the cell and results in the liberation of energy
2. Breathing and Respiration BREATHING 1. Mechanism by which organisms obtain oxygen from the air and release carbon dioxide 2. It is a physical process 3. It involves lungs of the organism RESPIRATION 1. It includes breathing and oxidation of food in the cells of the organism to release energy 2. It is a biochemical process 3. It involves the mitochondria in the cells where food is oxidized to release energy
Process which involves taking in oxygen into the cells, using it for releasing energy by burning food and then eliminating the waste products like carbon dioxide and water from the bodyBREATHINGMechanism by which organisms obtain oxygen from the air and release carbon dioxideIt is a physical processIt involves lungs of the organism
It is a catabolic process as the food is broken down into simpler form. In short, respiration is a biochemical activity taking place with in the protoplasm of the cell and results in the liberation of energy
( The anaerobic respiration in human muscle tissue produces lactic acid as an end product during vigorous physical exercise)
The respiratory system is the network of organs and tissues that help you breathe. It includes your airways, lungs, and blood vessels. The muscles that power your lungs are also part of the respiratory system. These parts work together to move oxygen throughout the body and clean out waste gases like carbon dioxide.
This presentation elaborates the economic crisis in Sri Lanka. It explains the causes of economic instability in Sri Lanka and the factors worsening it. Such miserable economic situation is presenting valuable lessons for other sister asian countries to counter their economic instability. Pakistan, a sister country of Sri Lanka is facing severe political and economic instability these days. Pakistan is learning from the Sri Lankan economic situation and tending to improve its economy but the extreme political instability is hurdling and exacerbating the economic crisis. However, policies are underway to counter the economic crisis and more probably Pakistan will escape the Sri Lankan experience.
Seminar of U.V. Spectroscopy by SAMIR PANDASAMIR PANDA
Spectroscopy is a branch of science dealing the study of interaction of electromagnetic radiation with matter.
Ultraviolet-visible spectroscopy refers to absorption spectroscopy or reflect spectroscopy in the UV-VIS spectral region.
Ultraviolet-visible spectroscopy is an analytical method that can measure the amount of light received by the analyte.
The ability to recreate computational results with minimal effort and actionable metrics provides a solid foundation for scientific research and software development. When people can replicate an analysis at the touch of a button using open-source software, open data, and methods to assess and compare proposals, it significantly eases verification of results, engagement with a diverse range of contributors, and progress. However, we have yet to fully achieve this; there are still many sociotechnical frictions.
Inspired by David Donoho's vision, this talk aims to revisit the three crucial pillars of frictionless reproducibility (data sharing, code sharing, and competitive challenges) with the perspective of deep software variability.
Our observation is that multiple layers — hardware, operating systems, third-party libraries, software versions, input data, compile-time options, and parameters — are subject to variability that exacerbates frictions but is also essential for achieving robust, generalizable results and fostering innovation. I will first review the literature, providing evidence of how the complex variability interactions across these layers affect qualitative and quantitative software properties, thereby complicating the reproduction and replication of scientific studies in various fields.
I will then present some software engineering and AI techniques that can support the strategic exploration of variability spaces. These include the use of abstractions and models (e.g., feature models), sampling strategies (e.g., uniform, random), cost-effective measurements (e.g., incremental build of software configurations), and dimensionality reduction methods (e.g., transfer learning, feature selection, software debloating).
I will finally argue that deep variability is both the problem and solution of frictionless reproducibility, calling the software science community to develop new methods and tools to manage variability and foster reproducibility in software systems.
Exposé invité Journées Nationales du GDR GPL 2024
Salas, V. (2024) "John of St. Thomas (Poinsot) on the Science of Sacred Theol...Studia Poinsotiana
I Introduction
II Subalternation and Theology
III Theology and Dogmatic Declarations
IV The Mixed Principles of Theology
V Virtual Revelation: The Unity of Theology
VI Theology as a Natural Science
VII Theology’s Certitude
VIII Conclusion
Notes
Bibliography
All the contents are fully attributable to the author, Doctor Victor Salas. Should you wish to get this text republished, get in touch with the author or the editorial committee of the Studia Poinsotiana. Insofar as possible, we will be happy to broker your contact.
What is greenhouse gasses and how many gasses are there to affect the Earth.moosaasad1975
What are greenhouse gasses how they affect the earth and its environment what is the future of the environment and earth how the weather and the climate effects.
Toxic effects of heavy metals : Lead and Arsenicsanjana502982
Heavy metals are naturally occuring metallic chemical elements that have relatively high density, and are toxic at even low concentrations. All toxic metals are termed as heavy metals irrespective of their atomic mass and density, eg. arsenic, lead, mercury, cadmium, thallium, chromium, etc.
Comparing Evolved Extractive Text Summary Scores of Bidirectional Encoder Rep...University of Maribor
Slides from:
11th International Conference on Electrical, Electronics and Computer Engineering (IcETRAN), Niš, 3-6 June 2024
Track: Artificial Intelligence
https://www.etran.rs/2024/en/home-english/
Travis Hills' Endeavors in Minnesota: Fostering Environmental and Economic Pr...Travis Hills MN
Travis Hills of Minnesota developed a method to convert waste into high-value dry fertilizer, significantly enriching soil quality. By providing farmers with a valuable resource derived from waste, Travis Hills helps enhance farm profitability while promoting environmental stewardship. Travis Hills' sustainable practices lead to cost savings and increased revenue for farmers by improving resource efficiency and reducing waste.
The use of Nauplii and metanauplii artemia in aquaculture (brine shrimp).pptxMAGOTI ERNEST
Although Artemia has been known to man for centuries, its use as a food for the culture of larval organisms apparently began only in the 1930s, when several investigators found that it made an excellent food for newly hatched fish larvae (Litvinenko et al., 2023). As aquaculture developed in the 1960s and ‘70s, the use of Artemia also became more widespread, due both to its convenience and to its nutritional value for larval organisms (Arenas-Pardo et al., 2024). The fact that Artemia dormant cysts can be stored for long periods in cans, and then used as an off-the-shelf food requiring only 24 h of incubation makes them the most convenient, least labor-intensive, live food available for aquaculture (Sorgeloos & Roubach, 2021). The nutritional value of Artemia, especially for marine organisms, is not constant, but varies both geographically and temporally. During the last decade, however, both the causes of Artemia nutritional variability and methods to improve poorquality Artemia have been identified (Loufi et al., 2024).
Brine shrimp (Artemia spp.) are used in marine aquaculture worldwide. Annually, more than 2,000 metric tons of dry cysts are used for cultivation of fish, crustacean, and shellfish larva. Brine shrimp are important to aquaculture because newly hatched brine shrimp nauplii (larvae) provide a food source for many fish fry (Mozanzadeh et al., 2021). Culture and harvesting of brine shrimp eggs represents another aspect of the aquaculture industry. Nauplii and metanauplii of Artemia, commonly known as brine shrimp, play a crucial role in aquaculture due to their nutritional value and suitability as live feed for many aquatic species, particularly in larval stages (Sorgeloos & Roubach, 2021).
Richard's aventures in two entangled wonderlandsRichard Gill
Since the loophole-free Bell experiments of 2020 and the Nobel prizes in physics of 2022, critics of Bell's work have retreated to the fortress of super-determinism. Now, super-determinism is a derogatory word - it just means "determinism". Palmer, Hance and Hossenfelder argue that quantum mechanics and determinism are not incompatible, using a sophisticated mathematical construction based on a subtle thinning of allowed states and measurements in quantum mechanics, such that what is left appears to make Bell's argument fail, without altering the empirical predictions of quantum mechanics. I think however that it is a smoke screen, and the slogan "lost in math" comes to my mind. I will discuss some other recent disproofs of Bell's theorem using the language of causality based on causal graphs. Causal thinking is also central to law and justice. I will mention surprising connections to my work on serial killer nurse cases, in particular the Dutch case of Lucia de Berk and the current UK case of Lucy Letby.
hematic appreciation test is a psychological assessment tool used to measure an individual's appreciation and understanding of specific themes or topics. This test helps to evaluate an individual's ability to connect different ideas and concepts within a given theme, as well as their overall comprehension and interpretation skills. The results of the test can provide valuable insights into an individual's cognitive abilities, creativity, and critical thinking skills
1. LECTURE 5: RESPIRATORY SYSTEM
INTRODUCTION
The respiratory system is composed of structures involved in ventilation (airflow to and from the lungs) and gas
exchange to supply blood with oxygen and remove carbon dioxide from the blood. The respiratory system does
this through ventilation, gas exchange between alveoli and capillaries, transportation of oxygen from the lungs
to the cells; gas exchange between cells and capillaries and delivery of carbon dioxide from the cells to the
lungs. In summary events of respiration includes ventilation, external and internal respiration, and cellular
respiration.
Ventilation activities ensure that air moves in and out of the alveoli in sufficient quantities to supply the needs
of the cells involved in oxidative cell respiration. Every cell in our body needs energy, and they obtain their
energy via cellular respiration (aerobically means need oxygen), thus oxygen should be delivered to each cell
continuously. Our cardiovascular system provides a link between the lungs and all the cells throughout the
body. Therefore the ultimate function of breathing is to deliver oxygen to cells, where it takes part in the
reactions of cellular respiration that liberate energy from nutrient molecules and get rid of carbon dioxide,
which maintains the pH of the internal environment.
The passageway that carries air from nose to the alveoli and from alveoli to the nose makes up the respiratory
tract. The respiratory tract is divided into upper (nose, nasal cavity, sinuses and pharynx) and lower (larynx,
trachea, bronchi, bronchiole, and alveoli) respiratory system. Air enters the upper respiratory system it is
filtered, humidified and warmed, before reaching the lungs i.e. upper respiratory system filters, worms and
humidifies incoming air to protect the more delicate surface of lower respiratory system. Think of the mucus
layer of the respiratory epithelium as a sticky flypaper that traps potentially troubling particles (flies or
microbes) from the surrounding airstream.
The lower respiratory system conduct air to the air filled pockets (called alveoli) where gas exchange occurs
between air and blood i.e. oxygen of the inhaled air from alveoli diffuses into the capillaries and carbon dioxide
diffuses from the capillaries to the alveoli. After the gas exchange the carbon dioxide follows the same path out
of the lungs when we exhale.
OVERVIEW
1. The respiratory system consists of passageways that filter incoming air and ultimately transport it into
the microscopic air sacs where gases are exchanged.
2. The entire process of exchanging gases between the atmosphere and body cells is called respiration.
3. Respiration includes 5 parts:
a. Ventilation = breathing
b. External respiration = air into lungs gas exchange (O2 load into the capillaries/ CO2 unload
from the capillaries) air out i.e. exchange between atmospheric air (external environment) and
capillaries or you could say that external respiration is diffusion of gases between the alveoli and
the circulating blood.
c. Transport of respiratory gases = gases in blood transported from lungs to body cells and back
to lungs i.e. delivery of oxygen from the lungs to the cells and delivery of carbon dioxide from
the cells back to the lungs
d. Internal respiration = exchange of gases at body capillaries (O2 unload from capillaries to the
cell/CO2 load from cells to the capillaries i.e. oxygen dissociates from Hb and diffuses out of
RBC and then out of capillaries and enter the cells of peripheral tissue; carbon dioxide diffuses
from the cells of peripheral tissue into the capillaries and then into the RBC and some bind to Hb
and the rest is converted to bicarbonate ion).
e. Cellular respiration = use of oxygen by cells to produce energy (production of CO2).
f. Only ventilation and external respiration are accomplished by respiratory system organs.
Transport of respiratory gases and internal respiration is achieved by cardiovascular system and
2. cellular respiration is achieved by cellular metabolism (chemical reactions that take place inside
the cell)
WHY WE BREATH?
Respiration is necessary because of cellular respiration, the process by which animal cells use oxygen to release
energy from nutrients we eat. The metabolic waste gas, carbon dioxide is produced during cellular respiration,
and it must be transported to the lungs to be expelled.
ORGANS OF THE RESPIRATORY SYSTEM
The organs of the respiratory system can be divided into two groups, or tracts. Those in the upper respiratory
tract include the nose, nasal cavity, sinuses, and pharynx. Those in the lower respiratory tract include the
larynx, trachea, bronchial tree, and lungs.
UPPER RESPIRATORY SYSTEM
1. The upper respiratory organs are lined with mucous membranes. Its function include to: warm incoming
air; moisten incoming air; entrap dust, microorganisms, and particles
a. Epithelium over connective tissue with many goblet cells (mucus).
i. The mucus functions to trap debris.
ii. The cilia beat the debris to the pharynx to be swallowed and destroyed by digestive
enzymes. Note: A healthy respiratory system is continuously cleansed. The sticky mucus
produced by the mucus cells batches the exposed surface of respiratory passageway. As
air passes through the passage way sticky mucus traps dirt, microorganisms, debris and
pathogens. The continuous beating of cilia sweeps trapped material toward the mouth
(pharynx), where they can be swallowed and eliminated by the stomach acid. Smoking
greatly impairs this housekeeping by slowing the beating of cilia. In cystic fibrosis the
mucus cells produce abnormally thick and sticky mucus, thus beating of cilia cannot
sweep the dense mucus. Mucus accumulates and restricts airflow and could block
smaller air passageways.
iii. This tissue also serves to warm and moisten incoming air.
2. Nose (external nares or nostrils)
a. Nose consists of or includes bone and cartilage with internal hairs (hairs traps large particles i.e.
filters air)
3. Nasal cavity (separated by nasal septum)
a. Bone and cartilage of nasal cavity are lined with mucous membranes
3. b. Warms and moistens incoming air
c. Olfactory reception
d. Resonating chambers for speech
4. Nasal conchae
a. Within the nasal cavity there are superior,
middle, and inferior bones called conchae
b. Conchae divide nasal cavity into a series
of groove-like passageway
c. Conchae are lined by mucous membranes
d. Function of nasal conchae is to increase
turbulence of incoming air in order to
better warm, moisten, and filter. As air
passes through the conchae, it create
turbulence in the air so as to trap small
particulates in mucus i.e. passing air will
bounce up and down and microorganism
and small particles will also bounce, and
as they bounce up and down small
particles and microorganisms will stick to
the sticky mucus.
5. Paranasal sinuses
a. Recall from A&P I that sinuses are air-
filled spaces in the frontal, sphenoid,
ethmoid, and maxillary bones of the skull.
These spaces open into the nasal cavity
and are lined with mucous membranes that
are continuous with the lining of the nasal
cavity, so mucus secretions drain from the
sinuses into the nasal cavity
b. During inflammation (swollen of membrane) of the membrane due to nasal infections or allergic
reactions the opening to the nasal cavity could become block and prevent drainage of mucus
secretion into nasal cavity. This may increase pressure in a sinus and cause headache.
6. Pharynx (or throat)
a. It is a passageway for air and food i.e. shared by both respiratory system and digest system.
b. Pharynx is divided into three parts:
i. Nasopharynx (uppermost, behind nasal cavity)
ii. Oropharynx (middle, behind oral cavity) – this is the portion of pharynx that is shared by
both digestive and respiratory systems
iii. Laryngopharynx (lowest)
LOWER RESPIRATORY SYSTEM
Organs of lower respiratory system include:
1. Larynx (or voice box)
a. Larynx consists of nine pieces of cartilage: 3 large cartilages and 3 pairs of small cartilages. The
3 large cartilages of larynx include:
i. Thyroid cartilage (Adam's apple)
ii. Epiglottis closes off the airway during swallowing.
1. During swallowing the larynx is elevated and the epiglottis folds back over the
glottis, preventing food and water particles from entering into respiratory tract i.e.
epiglottis is an elastic cartilage that shields the opening to the larynx during
4. swallowing.
2. Glottis = triangular slit opening between two pairs of vocal cords i.e. inhaled air
leaves the pharynx and enters the larynx through a narrow opening called glottis.
Glottis is the opening to the larynx.
iii. Cricoid cartilage = ring of hyaline cartilage attached to first ring of trachea site of
tracheotomy.
b. Voice production
i. Sound production at the larynx is called phonation. Phonation is the first step in speech
production. Phonation (sound) produced by vocal fold has to be articulated and modified
by tongue, teeth, lips, nasal cavity to produce speech.
ii. Mucous membranes form two pairs of folds.
1. Upper ventricular folds (false vocal cords)
2. Lower vocal folds (true vocal cords)
3. Triangular space between them = glottis.
iii. Sound (phonation) originates from vibration of the vocal folds as air passes through the
open glottis.
2. Trachea (windpipe)
a. Trachea or windpipe is a tough, flexible tube that receive air from the larynx and pass it to the
bronchi
b. Location = mediastinum anterior to esophagus extends from larynx to T5 (fifth thoracic
vertebrae)
c. Structure: 16-20 incomplete rings of hyaline cartilage = C-rings
i. C shape cartilages hold them open and prevent its collapse or overexpansion as pressure
changes within the respiratory system.
d. Carina = point where trachea divides into right & left primary bronchi i.e. when trachea branches
into left and right, it becomes primary bronchi.
e. Function = support against collapse, continue to warm, moisten & filter air.
3. Bronchial Tree
a. The bronchial tree consists of branched airways leading from the trachea to the microscopic air
sacs in the lungs. Its branches begin with the right and left primary bronchi
b. The openings of the primary bronchi are separated by a ridge of cartilage called the carina
c. Each primary bronchus enters its respective lung (left bronchus enters left lung and right
bronchus enters right lung)
d. Primary bronchus branches into secondary or lobar bronchi, which branch to each lobe i.e. at
the entrance to the lungs primary bronchi will branch into secondary bronchi and then each
secondary bronchus will enter one lobe of the lung (Three branch from the right primary
bronchus, and two branch from the left)
e. Secondary bronchi will branch into tertiary or segmental bronchi
f. Each tertiary bronchi branches several times giving rise to multiple bronchioles
4. Bronchioles
a. Each bronchiole branches further to form terminal bronchioles
b. Each terminal bronchiole subdivides into microscopic branches called respiratory bronchioles
(lined by simple squamous epithelium), which subdivide into several alveolar ducts, which
terminate into numerous alveoli and alveolar sacs.
c. As bronchi branches: Epithelium changes from ciliated to non-ciliated; Cartilage decreases;
Smooth muscle increases
5. 5. ALVEOLI (microscopic air sacs)
a. Alveoli are thin-walled, microscopic air sacs that open to an alveolar sac. Air can diffuse freely
from the alveolar ducts, through the alveolar sacs, and into the alveoli (The lungs contain more
than 300 million alveoli)
b. Wall consists of epithelial cells, septal cells and macrophages
i. Epithelial cells called Type I Alveolar cells form a continuous simple squamous lining
of the alveolar wall.
ii. Septal cells called Type II Alveolar cells are scattered among the squamous lining.
These cell s produce (secrete) surfactant
1. Surfactant lowers surface tension and prevents alveolar collapse i.e. surfactant
helps prevent the alveoli from collapsing.
iii. Alveolar Macrophages remove dust particles and other debris from alveolar spaces.
6. A diagrammatic view of alveolar structure. A single capillary may be involved in gas exchange with several
alveoli simultaneously
iv. Alveolar-Capillary (Respiratory) Membrane
1. Function = allows for rapid diffusion of gases (from area of high concentration
to area of low concentration and/or form area of high pressure to are of low
pressure).
2. This exchange of gas between alveoli and capillaries are called External
Respiration
6. Lungs
a. Location = thoracic cavity
b. Description: The lungs are soft, spongy, paired, cone-shape organs in the thoracic cavity;
covered by pleural (serous) membranes. A layer of serous membrane, the visceral pleura, is
firmly attached to the surface of each lung, and this membrane folds back at the hilus to become
the parietal pleura
i. visceral pleura – covers the outer surfaces of the lungs
ii. Parietal pleura – covers the inner surface of the thoracic wall and extends over the
diaphragm.
iii. Pleural cavity filled with serous fluid.
7. c. Each lung is divided into lobes by fissures:
i. Right lung has 3 lobes: superior, middle, and inferior.
ii. Left lung has 2 lobes: superior and inferior
iii. Each lobe: receives a secondary bronchus
iv. Each lobe is divided into lobules (bronchopulmonary segment)
BREATHING MECHANISM/VENTILATION
Introduction: Recall that the function of the respiratory system is to supply cells with oxygen and remove
carbon dioxide. The breathing mechanism is called ventilation. Movement of the diaphragm and rib cage
causes change in the volume of the thoracic cavity. When the shape of thoracic cavity changes, the lungs will
either expands or compresses, and consequently expansion and compression changes the air pressure within the
lungs. Air will flow from area of higher pressure to area of lower pressure. The direction of air flow is
determined by the difference between atmospheric pressure and intrapulmonary pressure (pressure inside the
lungs or pressure inside the respiratory tract).
1. Gas Law
a. Boyle’s Law: states that pressure and volume are inversely (indirectly) proportional i.e. volume
and pressure have inderct relationship. When volume is decreased pressure increases, and when
volume is increase, pressure decreases.
b. Dalton’s law: in a mixture of gases like air, the total pressure is the sum of the individual partial
pressures of the gases in the mixture. The pressure of gas determines the rate at which it will
diffuse from region to region. Gas will diffuse from are of high pressure to area of low pressure.
c. Henry’s law: The amount of gas in solution is directly proportional to their partial pressure i.e.
more pressure means more gasses in solution. For example unopened can of soda will have high
pressure inside and high pressure means more gas will be in the solution, but when a can of soda
is opened, pressure decreases and gas escapes from the solution.
2. Ventilation involves two actions, inspiration and expiration.
a. Inspiration (inhalation) = breathing air in.
i. Elevation of rib cage and contraction of the diaphragm enlarges the thoracic cavity.
Increase in the size of thoracic cavity mean the pressure inside the lungs becomes lower
than the atmospheric pressure, air flows into the lung i.e. when atmospheric pressure is
higher than lung pressure air moves into the lung
ii. During inspiration: The diaphragm muscle pushes downward i.e. The size of thoracic
cavity increases; The pressure in the thoracic cavity decreases (Boyles' Law); The air
pressure inside the thoracic cavity (lungs) is less than the atmospheric pressure and
therefore air rushes into lungs to equalize the pressure gradient.
b. Expiration = breathing out depends on two factors: the elastic recoil of tissues that were
stretched during inspiration (i.e. tissues bouncing back to shape); the inward pull of surface
8. tension due to the alveolar fluid. The first event in expiration is the diaphragm and external
intercostal respiratory muscles relax.
i. When the rib cage returns to its original position and the diaphragm relaxes the volume
of the thoracic cavity decreases. Pressure rises, and air moves out of the lungs.
3. Respiratory Distress Syndrome (RDS) in premature newborns (collapsed lungs) occurs due to the lack
of surfactant in the alveoli.
4. Respiratory Volumes and Capacities
a. Are measured by a spirometer
b. Include the following 4 volumes from which 4 capacities may be calculated.
i. One inspiration plus the following expiration is called a respiratory cycle. Tidal Volume
= amount (volume) of air that enters the lungs during normal inspiration and leaves the
lungs during normal expiration; approximately 500 ml. In other word it is the volume of
air that enters or leaves the lungs during a normal respiratory cycle.
ii. Inspiratory Reserve Volume (IRV) = the amount of air the can be forcibly inhaled after
a normal tidal inspiration; approximately 3000 ml.
iii. Expiratory Reserve Volume (ERV) = the amount of air that can be forcibly exhaled
after a normal tidal expiration; approximately 1100 ml.
iv. Residual Volume (RV) = amount of air that always remains in lungs; approximately
1200 ml.
v. Vital Capacity (VC) = the maximum amount of air that can be exhaled after a maximum
inhalation.
vi. Inspiratory Capacity = total amount of air that can be inspired after a tidal expiration.
vii. Functional Residual Capacity = amount of air left in the lungs after a tidal expiration
viii. Total Lung Capacity = VC + RV; approximately 6 L.
9. 5. Alveolar Ventilation
a. Minute Ventilation = Amount of air that enters and exits respiratory system in one minute (tidal
volume multiplied by the number of breathing per minute)
b. Anatomic dead space (ADS) = air space in respiratory passageways not involved in gas
exchange;
CONTROL OF BREATHING
1. Normal breathing = rhythmic and involuntary.
2. Respiratory Center = Nervous Control
a. Located in pons & medulla of brain stem
b. Medullary Rhythmicity area composed of dorsal respiratory group which controls the basic
rhythm of breathing and ventral respiratory group which controls forceful breathing.
3. Factors Affecting Breathing
a. Chemoreceptors in carotid and aortic bodies of some arteries are sensitive to:
i. Low levels of oxygen
ii. High levels of CO2
1. Increase in CO2 level affect chemosensitive areas (central chemoreceptors) of
respiratory center and breathing rate and depth increases
iii. Hyperventilation is rapid, shallow breathing that increases O2 level and decrease in blood
CO2 concentration and a rise in pH. NOTE CO2 concentration and pH have inverse
(indirect) relationship. The higher the CO2, the lower the pH, the lower the CO2, the
higher the pH i.e. high CO2 = acidic pH; and low CO2 = base or alkaline pH
iv. Low pH increases breathing rate. High concentration of CO2, decreases pH (make pH
acidic)
ALVEOLAR GAS EXCHANGES
1. External Respiration = the exchange of oxygen and carbon dioxide between the alveoli and capillaries
at the lungs.
a. The pressure of gas determines the rate at which it will diffuse from region to region (Dalton's
Law).
b. In a mixture of gases, the amount of pressure that each gas creates = partial pressure.
c. In air that reaches the alveoli:
i. PO2 = 104 mm Hg (the partial pressure of oxygen in the alveoli is about 104)
ii. Partial pressure of deoxygenated blood at the pulmonary capillaries = 40
iii. Oxygen will diffuse from are of high pressure (alveoli) to are of low pressure (pulmonary
capillaries)
iv. PCO2 = 40 mm Hg (the partial pressure of carbon dioxide in the alveoli is about 40)
v. Partial pressure of carbon dioxide in the pulmonary capillaries are 45
vi. Carbon dioxide will diffuse from are of high pressure (pulmonary capillaries) to are of
low pressure (alveoli)
d. The partial pressure of a gas is directly related to the concentration of that gas in a
mixture.(Dalton’s Law of Partial Pressure)
e. Diffusion of gases through the respiratory membrane proceeds from where a gas is at high
partial pressure → low partial pressure.
f. The rate of diffusion of gases also depends on a number of factors, including the following:
1. gas exchange surface area
2. diffusion distance
3. Breathing rate and depth.
2. Internal Respiration = the exchange of oxygen and carbon dioxide between tissue capillaries and tissue
cells i.e. internal respiration is the process by which dissolved gases are exchanged between the blood
10. and interstitial fluids.
a. In tissue cell: pCO2 = 45 pO2 = 40
b. In tissue capillaries: pCO2 = 40 pO2 = 95.
c. Therefore, oxygen diffuses from the capillaries into the interstitial fluid and from interstitial
fluid into the cell and carbon dioxide diffuses from cell into the interstitial fluid and from
interstitial fluid into capillaries.
GAS TRANSPORT (in Blood)
1. Oxygen Transport
a. When oxygen diffuses into the capillaries from the alveoli, it binds with hemoglobin (Hb) in red
blood cells to form oxyhemoglobin. Recall that each hemoglobin could bind to 4 oxygen
molecules.
b. A weak bond is formed so oxygen can be delivered to the cells and then released when needed.
c. The release of oxygen from hemoglobin depends on many factors:
11. i. High blood [CO2] means need for oxygen
ii. Low blood pH (acidity) means high concentration of CO2, and high concentration of CO2
means acidic pH (low pH)
iii. High blood temperature, means increased physical activity thus it means need for more
oxygen. Recall from your A&P that heat is produced by skeletal muscle and distributed
by blood. High muscle activity means more heat.
d. Carbon Monoxide (CO) binds to hemoglobin more efficiently than oxygen i.e. hemoglobin has
more affinity to bind to carbon monoxide then to oxygen
i. If the hemoglobin (that is supposed to bind with oxygen) is bound to CO, much less Hb is
available to bind and transport oxygen to the tissues Hypoxia (oxygen deficiency) results
and cells die.
2. Carbon Dioxide Transport (CO2)
a. CO2 is transported in 3 forms:
i. Dissolved CO2= 7%
ii. Carbaminohemoglobin=23%
iii. Bicarbonate ions= 70%
b. In tissues, CO2 is produced by cellular respiration i.e. cells continuously use oxygen and organic
molecules (e.g. glucose) to generate ATP (energy to maintain homeostasis) and CO2 as a waste
product of cellular respiration). CO2 from the cell diffuses into the interstitial fluid and then from
the interstitial fluid it diffuses into the capillaries.
c. Once inside the capillaries, 7% of the CO2 will be dissolved in the plasma and transported to the
lungs as dissolved in the plasma
d. 93 % of the CO2 will enter the RBC (red blood cells).
e. Inside the RBC 23% of the CO2 will bind to hemoglobin and will be transported to the lungs as
bound to the hemoglobin
f. 70 % of CO2 inside the RBC will combine with H2O to form H2CO3 (Carbonic acid). Carbonic
acid dissociates to H+
and bicarbonate ion (HCO3
-
). Enzyme carbonic anhydrase facilitate this
reaction)
CO2 + H2O → H2CO3 → H+
+ HCO3
-
12. 1) In the capillaries 93% of CO2 will enter RBC.
Inside RBC 70 % of CO2 will combine with H2O
and form carbonic acid; 23 % will bind to
hemoglobin (Hb) and form carbaminohemoglobin.
2)Carbonic acid is a weak acid therefore it will
quickly dissosiate into bicarbonate and hydrogen
ions with the help an enzyme called carbonic
anhydrase
3) hydrogen ions will bind to hemoglobin and
bicarbonate will move out of the RBC via chloride
shift in exchange for Cl i.e. chlorine will enter RBC
and Bicarbonate will move out of the RBC.
4) carbon dioxide will be delivered to the lungs
(mainly in the form of Bicarbonate ions, but 23 %
bound to Hb and 7% dissolved in the plasma). At
the lungs the reaction is reversed: Bicarbonate
enters RBC and chlorine moves out of the RBC;
Hydrogen ion that was bound to Hb will be
dissociated; Hydrogen ion and bicarbonate will
combine and form carbonic acid; carbonic acid will
dissociate into carbon dioxide and water; carbon
dioxide will diffuse from RBC to the plasma and
from plasma to alveoli; also carbon dioxide that
was bound to Hb, will dissociate from it and diffuse
out of RBC and then diffuse to the alveoli.
LIFE SPAN CHANGES
1. The lungs, respiratory passageways, and alveoli undergo aging-related changes exacerbated by exposure
to pollutants, smoke, etc., increasing the risk of developing respiratory illnesses.
2. Loss of cilia, thickening of mucus, and impaired macrophages increases the risk of infection as one age.
3. Breathing becomes more difficult as one ages due to:
a. calcified cartilage
b. skeletal changes
13. c. altered posture
d. Replacement of bronchiole smooth muscle by fibrous connective tissue.
4. Vital Capacity decreases with age.
a. The lungs contain a greater proportion of “stale” air.
b. Alveoli coalesce and become shallower, slowing gas exchange.
Summary of Organs of Respiratory System and their Function
Part Description Function
Nose Part of face centered above the mouth
and inferior to the space between the
eyes
Nostrils provide entrance to nasal cavity; internal hairs
begin to filter incoming air
Nasal
cavity
Hollow space behind nose Conducts air to pharynx; mucous lining filters, warms,
and moistens incoming air
Sinuses Hollow spaces in various bones of the
skull
Reduce weight of the skull; serve as resonant
chambers
Pharynx Chamber posterior to the nasal cavity,
oral cavity, and larynx
Passageway for air moving from nasal cavity to larynx
and for food moving from oral cavity to esophagus
Larynx Enlargement at the top of the trachea Passageway for air; prevents foreign objects from
entering trachea; houses vocal cords
Trachea Flexible tube that connects larynx with
bronchial tree
Passageway for air; mucous lining continues to filter
air
Bronchial
tree
Branched tubes that lead from the
trachea to the alveoli
Conducts air to the alveoli; mucous lining continues to
filter incoming air
Lungs Soft, cone-shaped organs that occupy
a large portion of the thoracic cavity
Contain the air passages, alveoli, blood vessels,
connective tissues, lymphatic vessels, and nerves of
the lower respiratory tract
Summary of divisions of Respiratory System
Organs Function
Upper respiratory System Nasal cavity, sinuses,
pharynx
filtered, warmed, and humidified
incoming air
Lower respiratory system Larynx, trachea, bronchi,
bronchiole, alveoli
Continue filtering air, alveoli allows for
gas exchange