IMAT Biology Lesson 6.6 | Anatomy and Physiology | Respiratory System

Summary

In this detailed lecture on the human respiratory system, Andre explores the anatomy and physiology of both the upper and lower respiratory tracts. He explains key structures like the nasal cavity, pharynx, larynx, trachea, bronchi, bronchioles, and alveoli, emphasizing their roles in gas exchange. The lecture covers the mechanics of breathing, including muscle involvement and pressure changes, and introduces lung volumes and capacities measured by spirometry. Finally, Andre touches on how gases like oxygen and carbon dioxide are transported in the blood, laying the foundation for understanding respiratory and circulatory system diseases.

Takeaways

• 🧠 Introduction to the anatomy and physiology of the human respiratory system.
• 👃 The upper respiratory tract includes the nasal cavity, pharynx, and larynx, which contains the vocal cords.
• 🔄 The lower respiratory tract begins with the trachea, which splits into the primary bronchi leading to the lungs.
• 🌬️ The bronchi divide into smaller tubes called terminal bronchioles, which further divide into respiratory bronchioles and alveolar ducts ending in alveoli where gas exchange occurs.
• 🫁 The diaphragm and intercostal muscles are crucial for lung contraction and expansion, facilitating breathing.
• 💨 Gas exchange occurs in the alveoli through diffusion, driven by differences in partial pressures of oxygen and carbon dioxide between alveoli and capillaries.
• 🦠 The trachea and bronchi have cartilage and goblet cells that produce mucus, helping trap and expel pathogens.
• 💪 Smooth muscles in the trachea and bronchi can contract to adjust airflow, responding to environmental conditions or allergic reactions.
• 🔍 Gas transport in the blood: Oxygen is carried by hemoglobin, while carbon dioxide is mostly transported as hydrogen carbonate in the plasma.
• 📉 Spirometry measures lung volumes and capacities, including tidal volume, vital capacity, and residual volume, which are critical for understanding respiratory health.

Q & A

What is the primary function of the nasal cavity in the respiratory system?

The primary function of the nasal cavity is to filter, warm, and humidify the air we breathe in.

What are the main anatomical structures of the upper respiratory tract?

The main anatomical structures of the upper respiratory tract include the nasal cavity, pharynx, and larynx.

What is the role of the trachea in the respiratory system?

The trachea serves as a passage for air to travel from the upper respiratory tract to the lower respiratory tract and is supported by cartilage to keep it open.

Describe the pathway of air from the trachea to the alveoli.

Air travels from the trachea to the primary bronchi, then to the terminal bronchioles, respiratory bronchioles, alveolar ducts, and finally reaches the alveoli where gas exchange occurs.

What is the function of the diaphragm in respiration?

The diaphragm contracts and flattens to increase the volume of the thoracic cavity, reducing the pressure and allowing air to flow into the lungs. It relaxes to help expel air during exhalation.

How does gas exchange occur in the alveoli?

Gas exchange occurs in the alveoli through diffusion, where oxygen moves from the alveoli into the blood in the capillaries, and carbon dioxide moves from the blood in the capillaries into the alveoli.

What are goblet cells and what is their function in the respiratory system?

Goblet cells are cells that produce mucus to trap viruses, bacteria, and other particles, preventing them from entering the lungs and causing infection.

What is the difference between the right and left lungs in terms of lobes?

The right lung has three lobes, while the left lung has two lobes.

Explain the concept of partial pressure in the context of gas exchange.

Partial pressure refers to the pressure exerted by a specific gas in a mixture of gases. Gas exchange occurs because gases move from areas of higher partial pressure to areas of lower partial pressure.

What happens during anaphylactic shock in the respiratory system?

During anaphylactic shock, the smooth muscles in the trachea and bronchus contract, narrowing the airways and making breathing difficult.

What is the function of the cilia in the respiratory system?

Cilia are tiny hair-like projections that move mucus and trapped particles out of the respiratory tract, helping to keep the airways clear.

What are the different volumes and capacities measured in a spirogram?

A spirogram measures tidal volume (normal breathing volume), total lung capacity, residual volume (air left in lungs after exhalation), functional residual capacity (residual volume plus expiratory reserve volume), inspiratory reserve volume, expiratory reserve volume, and vital capacity (inspiratory reserve volume plus tidal volume plus expiratory reserve volume).

How is carbon dioxide transported in the blood?

Carbon dioxide is transported in the blood in three main ways: dissolved in plasma (5%), as hydrogen carbonate (85%) after combining with water and an enzyme, and as carbaminohemoglobin (10%) after combining with hemoglobin.

What is the significance of the pleural cavity in the respiratory system?

The pleural cavity, the space between the parietal and visceral pleura, contains a small amount of fluid that reduces friction during breathing and helps maintain the negative pressure needed for lung expansion.

What happens to intrapleural pressure during inspiration?

During inspiration, the intrapleural pressure decreases as the thoracic cavity volume increases, allowing air to flow into the lungs.

What is the relationship between volume and pressure in the lungs?

Volume and pressure in the lungs are inversely related; increasing the volume of the lungs decreases the pressure, and decreasing the volume increases the pressure, facilitating the movement of air in and out of the lungs.

Outlines

00:00

🫁 Introduction to the Respiratory System

The video introduces the respiratory system, detailing the anatomy of the upper and lower respiratory tracts. Key structures include the nasal cavity, pharynx, larynx, trachea, bronchi, and alveoli. The importance of the diaphragm and intercostal muscles in breathing is also explained.

05:01

🌬️ Gas Exchange Process

This section covers the process of gas exchange in the alveoli, emphasizing the roles of oxygen and carbon dioxide partial pressures. It explains how oxygen moves from the alveoli to the capillaries and how carbon dioxide is transferred in the opposite direction.

10:01

💨 Role of Smooth Muscle and Goblet Cells

The role of smooth muscle, goblet cells, and cilia in the respiratory system is discussed. Smooth muscles help regulate airway diameter, while goblet cells produce mucus to trap pathogens. The section also explains how these features protect against respiratory infections.

15:02

💉 Respiratory Physiology and Pressure Dynamics

This part details the physiology of respiration, focusing on the mechanics of inspiration and expiration. It explains how changes in volume and pressure facilitate airflow into and out of the lungs, and the roles of various pressures, including atmospheric, intrapleural, and intrapulmonary pressures.

20:04

📈 Lung Volumes and Capacities

The concluding section introduces the concept of lung volumes and capacities, including tidal volume, total lung capacity, residual volume, functional residual capacity, inspiratory reserve volume, expiratory reserve volume, and vital capacity. The importance of these measurements in respiratory function is highlighted.

Keywords

💡Respiratory system

The respiratory system is the network of organs and tissues that help you breathe. It includes the airways, lungs, and blood vessels. In the video, the respiratory system is divided into the upper and lower respiratory tracts, covering structures from the nasal cavity to the alveoli where gas exchange occurs.

💡Nasal cavity

The nasal cavity is the hollow space within the nose. It is the first part of the upper respiratory tract, responsible for filtering, warming, and humidifying the air we breathe. In the video, the nasal cavity is identified as the entry point of air into the respiratory system.

💡Pharynx

The pharynx is the part of the throat behind the nasal cavity and mouth. It serves as a pathway for the movement of air into the larynx and food into the esophagus. The video highlights the pharynx as a crucial component of the upper respiratory tract.

💡Larynx

The larynx, also known as the voice box, houses the vocal cords and is involved in breathing, producing sound, and protecting the trachea against food aspiration. The video discusses the larynx's role in sound production and its location in the upper respiratory tract.

💡Trachea

The trachea, or windpipe, is a tube that connects the larynx to the bronchi, allowing air passage to the lungs. It is part of the lower respiratory tract and is supported by cartilage to maintain its structure. The video describes the trachea as a critical airway leading to the lungs.

💡Bronchi

The bronchi are the two large tubes that branch off from the trachea into the lungs, further dividing into smaller bronchioles. They are part of the lower respiratory tract. In the video, the bronchi are described as pathways for air to reach the lungs and are discussed in the context of branching into the primary bronchi.

💡Alveoli

Alveoli are tiny air sacs in the lungs where gas exchange occurs. Oxygen is absorbed into the blood, and carbon dioxide is expelled from the blood into the alveoli. The video emphasizes the alveoli as the primary site of gas exchange in the respiratory system.

💡Diaphragm

The diaphragm is a large, dome-shaped muscle located below the lungs that plays a key role in breathing by contracting and relaxing to change the volume of the thoracic cavity. The video explains the diaphragm's function in stimulating lung contraction and its role in the mechanics of breathing.

💡Gas exchange

Gas exchange is the process of oxygen entering the blood and carbon dioxide being expelled from the blood, primarily occurring in the alveoli. The video discusses gas exchange in detail, explaining how it is driven by differences in partial pressure between the alveoli and the blood.

💡Partial pressure

Partial pressure refers to the pressure exerted by a single type of gas in a mixture of gases. It is crucial in the process of gas exchange in the lungs. The video explains how differences in partial pressure of oxygen and carbon dioxide drive their movement between the alveoli and the capillaries.

💡Pleural cavity

The pleural cavity is the thin fluid-filled space between the two layers of the pleura (the visceral and parietal pleura) that surrounds the lungs. The video mentions the pleural cavity when discussing lung anatomy and the mechanics of breathing.

💡Intercostal muscles

Intercostal muscles are the muscles located between the ribs that assist with the expansion and contraction of the thoracic cavity during breathing. The video discusses their role in breathing by explaining how they help inflate and deflate the lungs.

💡Spirogram

A spirogram is a graphical representation of lung volumes and capacities measured during breathing. It includes metrics like tidal volume, vital capacity, and residual volume. The video introduces the spirogram to explain different lung volumes and capacities.

💡Hemoglobin

Hemoglobin is a protein in red blood cells that carries oxygen from the lungs to the body's tissues and returns carbon dioxide from the tissues back to the lungs. The video explains hemoglobin's role in oxygen transport and its importance in the respiratory system.

💡Carbonic anhydrase

Carbonic anhydrase is an enzyme that catalyzes the conversion of carbon dioxide and water to carbonic acid, which then dissociates into bicarbonate and hydrogen ions. The video highlights its role in the transport of carbon dioxide in the blood.

💡Tidal volume

Tidal volume is the amount of air that is inhaled or exhaled during normal breathing. The video refers to tidal volume when discussing the measurement of lung volumes and capacities.

💡Vital capacity

Vital capacity is the maximum amount of air a person can exhale after maximum inhalation. It includes the tidal volume, inspiratory reserve volume, and expiratory reserve volume. The video explains vital capacity in the context of measuring lung function.

Highlights

Introduction to the anatomy of the respiratory system, starting with the upper respiratory tract.

Explanation of the nasal cavity and pharynx as parts of the upper respiratory tract.

Description of the larynx and its function, including the role of the vocal cords.

Distinction between the upper and lower respiratory tracts, with the trachea marking the division.

Detailed breakdown of the lower respiratory tract, including the trachea, bronchi, and lungs.

Explanation of the bronchial tree, from primary bronchi to alveoli, and their roles in gas exchange.

Role of the diaphragm and intercostal muscles in respiration.

Identification of the pleural cavity and its components: parietal pleura, visceral pleura, and the pleural cavity space.

Mechanism of gas exchange in the alveoli, focusing on partial gas pressures of oxygen and carbon dioxide.

Differentiation of the right lung (three lobes) and left lung (two lobes).

Explanation of trachea and bronchi structures, including cartilage, goblet cells, and smooth muscle.

Function of cilia and goblet cells in protecting the respiratory system from pathogens.

Detailed look at the smooth muscle and its role in regulating airway resistance.

Carbon dioxide transportation in the blood, including the formation of hydrogen carbonate.

Overview of lung volumes and capacities, including tidal volume, residual volume, and total lung capacity.

Description of inspiratory and expiratory reserve volumes and their importance in lung function.

Definition of vital capacity and its components.

Transcripts

[Music]

hi everybody my name is andre and

welcome back to med school eu

today we are going to continue on with

this lengthy topic of anatomy physiology

of

systems

in humans and more specifically today we

are going to talk about the respiratory

system we'll begin the unit with

anatomy of the respiratory system

so

we have a couple of labels to go through

just

anatomical labels here

so beginning with the upper respiratory

tract

we got the nasal cavity up at the top

so this is the nasal

cavity

next this

little part right here at the back of

the throat that's called the pharynx

that's fairings

going a little bit lower past the

pharynx we got the larynx and in the

larynx

we've got our vocal cords so this is

where

the sound comes from that comes from the

vocal cords in the larynx now going

further down there's going to be a

divide here

between the

upper respiratory tract and the lower

respiratory tract so these all of these

anatomical structures are part of the

upper respiratory tract

and going below down here to the trachea

this is the trachea

and anything below the trachea is the

lower respiratory tract

so

splitting off from the trachea to the

right lung and the left lung this big

part right here is called the primary

bronchi

and past the the bronchi of course we've

got here the lungs and we're going to go

into further anatomy about the lungs

because there's going to be further

breakdowns and

splitting of these tubes from the

bronchi

all the way down to the alveoli and

that's what we are going to discuss in

this one so here of course we got our

trachea as you can see it's covered in

cartilage

and the the next is the bronchi which we

have labeled already as you can see

they're pretty much identical on both

sides then this moves into terminal

bronchial so that's the

the smaller division here from the

bronchus

it becomes a terminal bronchiole and

from terminal bronchial we go into

respiratory bronchiole and finally this

goes into the alveolar duct and from the

alveolar duct we're gonna have

these little grape-like structures

called alve

oli

and gas exchange occurs

in the alveoli and

sporadically in the alveolar duct

however all these other structures the

bronchioles respiratory termin terminal

and

the bronchi the bronchus and the trachea

there's going to be no gas exchange

occurring only the alveoli and

sometimes alveolar duct depending on the

thickness of it now the structure that

goes right underneath is not shown here

but the structure that goes underneath

the lungs is called the diaphragm and

the diaphragm is responsible for

contraction

of the lungs so it's going to stimulate

breathing

as well as the intercostal muscles so

the muscles that go in between here are

called inter

so intercostal muscles the one that goes

that go between between the ribs and the

diaphragm at the bottom are going to be

responsible for

inflating and deflating the lungs and

we're going to discuss their primary

functions in the next few slides as well

so there are uh three more labels here

so we got the plural cavity so there's

going to be a space between

the two plurals so the

the outer plural is called the parietal

the inner plural is called the visceral

pleura and of course the space in

between is going to be called pleural

cavity so this is just a cavity

space in between the two pleura so

that's the general respiratory system

anatomy so now we are going to talk a

little bit about gas exchange as it

occurs in the alve

alveoli so for breathing in

the gas is primarily going to be oxygen

and the gas pressure here in

the capillary

is primarily going to be carbon dioxide

so we're going to offload the carbon

dioxide and we're going to load on the

oxygen and the reason that's going to

happen is because of partial gas

pressures

so

the partial gas pressure of oxygen in

the alveoli is going to be much greater

than in the capillary therefore the net

movement of gas is going to go to the

capillary and this is just a phenomenon

called diffusion

where it goes from an area of high

concentration to an area of lower

concentration in this case we're talking

about gases therefore we're going to

refer to as partial pressure so

higher partial pressure of gas is going

to move over to

the lower partial pressure of gas now

the same thing occurs with the carbon

dioxide the

atmospheric carbon dioxide partial

pressure is extremely low compared to

the capillary carbon dioxide partial

pressure because these capillaries are

going to bring deoxygenated blood from

the body and which will have metabolites

and carbon dioxide so carbon dioxide is

going to be taken up

by the alveoli again through diffusion

the same concept

where it goes from an area of higher

partial pressure to an area of

lower partial pressure of carbon dioxide

now the exact opposite occurs once these

travel to cells so these are not alveoli

anymore these are just cells

of the body now cells of the body are

going to have lots of carbon dioxide

in high concentrations so there's going

to be high partial pressure of carbon

dioxide but they're going to have low

oxygen so

the whole purpose of the circulatory

system is to deliver nutrients and

oxygen to the cells so they can operate

and do their primary functions so once

the

blood vessels are

able to circulate from the lungs over to

the cells again they're going to go

through the heart then the entire

respiratory system they're going to end

up in various cells of the body

and they're going to offload their high

partial pressure of oxygen onto the

cells because they're going to have low

partial pressure of oxygen and they're

going to uptake the high partial

pressure of carbon dioxide again the

same concept that occurs through

diffusion now before we take a look at

this chart right here

there's another phenomenon i wanted to

mention is that

the right lung

the right lobe

of

of the lung contains

three lobes and the left side so the

left lung contains two lobes so it's

it's a little bit smaller it doesn't

split up into as many lobes

the right lung has three the left lung

has two so that's another thing uh to

just keep in mind and here with this

chart

we are going to

discuss

various structures that

are involved within each of these

anatomical positions that we discussed

earlier so the trachea number of trachea

there's only one trachea that splits off

into two bronchi

so

for each side of the lung or each

bronchus i should say is going to split

off into thousands 48 000 of terminal

bronchials

and

something very important happens here is

that the trachea and the bronchus

have cartilage these are

they're going to have cartilage in

in their structures in order to support

that volume and the air that's coming in

so they're going to have cartilage there

they're also going to have goblet cells

that

will will produce mucus and they're

going to be responsible to keep out any

viruses or any bacteria that may enter

the respiratory system they're going to

keep out the flu the cold as we are we

get in contact with the flu virus the

coronaviruses

and just the regular respiratory viruses

that we get in the winter

they are going to be caught up by these

goblet cells and the cilia

goblet cells and cilia they're

responsible for creating mucus where all

of these

respiratory illnesses and all of these

viruses are going to be caught up and

the cilia

so these are little projections

the cilia are going to be pushing up

up the wall down to the trachea and in

reverse so that you can just cough it

out or breathe it out without

the virus attaching to receptors inside

the lungs and causing

an illness now another thing to know is

the trachea the bronchus and the

terminal bronchial have smooth muscle

so this this means they could

dilate they could stretch a little bit

which involves the

elastic tissue as well

so

up to the point of the terminal

bronchiole they are going to have smooth

muscle which could control

how wide the airway is going to be

so for example if you are out in a

colder environment the smooth muscle is

typically going to contract a little bit

to create resistance for the air so the

air is not going to pass as quickly and

you are not going to get cold air

entering the alveoli because that

obviously could cause

problems for the alveolar cells

therefore in order to buffer that

temperature of the air you're going to

have smooth muscle they're going to

contract and they're going to reduce the

diameter of the trachea and the bronchus

and

something very similar happens with

anaphylactic shock or

an allergic reaction where the trachea

and the bronchus the smooth muscles

there are going to contract and they're

gonna

make a narrow airway and that's when

problems occur uh with with breathing

and anaphylactic shock so as you can see

here as i mentioned previously the site

of gas exchange so the exchange that

occurs here and here

in terms of the carbon dioxide and the

oxygen only occurs in alveoli and the

alveolar duct

primarily in the alveoli however in some

cases alveolar duct as

as well there's going to be no gas

exchange in any of the bronchioles or

the bronchus or the trachea

important thing to remember is that

trachea and bronchus have goblet cells

that produce mucus

smooth muscle and cilia

are going to be all the way down to the

terminal bronchial but not the

respiratory bronchioles

and cartilage will only reside with the

trachea and the bronchus so when we

discuss the immune response we are going

to talk about the goblet cells and the

smooth muscle cells in greater detail

next we have a quick slide about the gas

content

of the blood

so

you should be familiar with how carbon

dioxide is going to be transported

within the blood because for oxygen of

course it's going to be

loaded onto hemoglobin and then

hemoglobin is going to be

caring

for oxygen molecules per

one

molecule of hemoglobin and there's going

to be millions molecules of hemoglobin

within each erythrocyte

so

that's typically how oxygen is going to

be carried within the red blood cell

however when when we have carbon dioxide

inside circulatory system

we're going to have a bit of a different

story so first

from the respiring cells so from our

cells we're going to get carbon dioxide

that will enter

the erythrocyte five percent of carbon

dioxide will be carried in solution

meaning it's going to be carried in the

plasma now the the rest

the highlighted areas is is what's going

to be important because the carbon

dioxide is going to combine with water

in some cases

using an enzyme called carbonic

anhydrase

and and it's going to create a molecule

of hydrogen carbonate so most of carbon

dioxide is

going to be transported as hydrogen

carbonate which is this molecule right

here hco3

minus 85 percent of the carbon dioxide

will go there and 10 percent of the

carbon dioxide will be converted

to carbon amino hemoglobin which is

simply when carbon dioxide combines with

the hemoglobin within the erythrocytes

so only about 10 percent

will be

carried the same as oxygen however the

rest of the carbon dioxide most of it

will be carried in the plasma as

hydrogen carbonate so now we're going to

talk about the physiology of

respirations and we're going to begin

with inspiration which is going to be

inhaling so getting

oxygen and

air into our lungs

so we are going to first make a couple

of labels here so of course we got the

diaphragm now this i

this yellow structure right here

this is more going to be like a zoom in

of an alveoli so i'm just going to label

it as

alveolar pressure p alveolar so the

gas pressure in the alveoli

then the

gas pressure that's going to be within

the lung is called

intrapulmonary pressure

inside the pleural cavity

we are going to have intrapleural

pressure

now the pressure difference between

the

intrapleural pressure and the pressure

inside the lung is called transpulmonary

pressure so these are all the

important and also we got atmospheric so

p atm

atmospheric pressure so all of these are

going to be involved in the breathing

anatomy and the physiology

of breathing now of course we have

intercostal muscles that go around the

side of the lungs and that's going to be

the ones in between the ribs

so let's go over some of the sequences

of events that occur

so we first are going to begin with

the inspiratory muscles that are going

to contract and that's going to be the

diaphragm so the diaphragm the

intercostal muscles are going to make

the rib cage

to push outward and up so the rib

this is how we are going to create more

volume

within

the

lungs

so we must remember that volume and

pressure

are inversely related so if we increase

the volume we are going to decrease the

pressure if we increase the pressure

we're going to decrease the volume so

what this does what the sequence this

first sequence does is it increases

volume because we are going to expand

the lungs and when we increase volume we

are going to decrease

the pressure

and we're going to decrease the pressure

to the point

where

the

atmospheric pressure is going to be

above

the

pressure inside the lungs and ultimately

the the pressure inside the alveoli

therefore the air can simply flow

through the fusion

from the atmosphere inside the lung and

into the alveoli because it's going to

move from

by the definition of diffusion it's

going to move from the higher partial

pressure of gas to lower partial

pressure of gas

so this what this uh what this really

does the ultimate thing is that the

intrapro

plural pressure pip

is going to decrease

because our lung volume has increased so

now because this has decreased number

three

the p atmospheric

is going to be above

p

i p

and we have

air flows inside so that's that's

typically how it occurs because

as the gases flow into the lungs down

its pressure gradient

until that intrapulmonary pressure is

zero so then

by the end of it once we fully have

inhaled

the atmospheric pressure is going to

equal to intrapulmonary

pressure

because of course the more air we get

inside

the more pressure it's going to create

and eventually it's going to equate

itself with the atmospheric pressure and

you can no longer breathe

any further you cannot breathe in any

further you cannot take up more air now

with expiration so breathing out we're

going to have something pretty much the

opposite occur so

we're going to have the inspiratory

muscles relax so the diaphragm and this

is all due to the recoil of the coastal

cartilages so if you stretch the

cartilage of the rib cage

it's obviously going to want to recoil

back because it's got its elastic fibers

and the elastic fibro fibers will

naturally want to recoil back to its

original form so that's going to create

that

pressure that tension

that

is going to counteract

the pressure that is created by the

diaphragm rising and the intercostal

muscles contracting next we're going to

have the thoracic volume

or the thoracic cavity volume decrease

meaning that it's going to increase

the pressure and as soon as the p

i p

pressure is above

the atmospheric pressure

then obviously the air

is going to flow out out into the

atmosphere because it's going to move

from higher pressure to lower pressure

environment and again it's going to

occur until finally the pip

the intrapleural pressure is going to

equate to

atmospheric pressure and you can no

longer breathe out

any further and the final thing that i'm

going to introduce you to is called a

spirogram so this is basically just a

measurement of

lung volumes and lung capacities so what

we have here is

the general breathing rate if we are

just breathing at a resting rate you're

sitting down on your chair you're

listening to this lecture your breathing

is going to be the tidal volume it's

only going to be about

maybe 500

milliliters of

of gas that's going to come in and out

in and out and that's going to be

labeled as tidal

volume

now the entire capacity of the lungs so

how how much air we could possibly have

inside the lungs if you fully breathe in

and all the air that was already in

there

that's going to be called the total lung

capacity

now there's something called residual

volume and residual volume is something

you cannot breathe out of course if you

were to breathe out

all the air that's inside your lung

your lung is going to collapse in on

itself so there's always going to be

some sort of

a little bit of air and that's typically

you see 1200 milliliters of

of air inside the lungs that is

constantly there even if you forcefully

expire you're still gonna have that

residual volume there and you cannot get

rid of it unless you puncture it along

and it flows out and at that point

you're gonna have a collapsed lung

and of course that's gonna create a lot

of problems

so that's the residual volume it's

extremely important for our vital

functions

now the volume that you could breathe

out and in addition with the residual

volume is called functional residual

capacity so that's the that's how much

that's the uh expiratory reserve volume

plus the residual volume so both of

these together an expiratory reserve

volume is how much air you could

forcefully breathe out

so if you're regularly breathing right

now and watching this lecture try to

breathe out as much as you can to the

point where you can no longer breathe

out anything else

that's your expiratory reserve volume

from the point of breathing out normally

to the point of fully forcefully

breathing out that's the expiratory

reserve volume now if you add that

together with the residual volume that

makes up functional

residual

capacity that is labeled here next we're

going to look at the inspiratory reserve

volume so that's completely the opposite

of the expiratory inspiratory reserve

volume is when you are doing your tidal

volume you're normally breathing and you

normally breathe in however

the rest that you can breathe in up to

your full

potential of breathing in that's going

to be the inspiratory reserve

volume now if you combine the expiratory

reserve volume plus tidal volume plus

inspiratory reserve volume so if you

were to

fully breathe in and then

fully breathe out

that's your vital

capacity that's what's called vital

capacity so all of these these three

different capacities and four different

types of volumes you should know by

heart so if they are identified on a

question

you would not be struggling to to know

what the question is really talking

about so this concludes our lecture on

the respiratory system in the next video

we are going to discuss the diseases

involved with the circulatory system as

well as the respiratory system

[Music]

you