exam 3 # 2

Respiratory System provides

for gas exchange between the blood and air.

what is the Upper Respiratory Tract: Head and Neck responsible for

• Filtering out harmful particles in “air”

• Humidifying “air”

• Delivering “air” to the lung

what is the Lower Respiratory Tract: Thorax responsible for

• Gas Exchange

• Prevention of infection

• Clean alveolar surface

what are Ventilatory Mechanics:

Skeletal muscle of diaphragm and intercostal muscles between ribs. Also: abdomenal muscles

does it take energy to inhale or exhale

inhale

What organs facilitate the movement of air to the lung

nose and trachea

how important is of mucus and the mucus membrane to the respiratory system

it is critical

air entry pathway

Nasal Cavity and Conchae-

– Sinus Cavities-

– Oral Cavity: poor airflow efficiency/low resistance

• Pharynx-

• Epiglottis and Glottis-

• Trachea-

• Bronchial Tree-

• Alveolus

Each lung and its lobes sit in what?

pleural cavity under a slight vacuum

what is often mistaken as an airway that can be fatal?

the esophagus

Each lung is surrounded by what?

pleural fluids

Air is distributed into lower respiratory air passages called

bronchi and bronchioles

(that ultimately lead to dead-end alveoli)

what does the Bronchial Tree do?

moves air from large to narrow branching airways

Bronchi have what?

cartilage and smooth muscle- for support

cilia- for cleaning

Nourished by bronchiolar artery

how big are Bronchioles

1mm diameter airways with smooth muscle for

changing diameter to needs

Bronchi in Order from biggest to smallest

Primary B

Secondary B

Tertiary B

leads to Bronchioles

Bronchioles in order from biggest to smallest

Terminal Bronchiole

Respiratory Bronchiole

leads to Alveoli(Gas Exchange)

airflow in lung pathway to alveoli

Primary B

Secondary B

Tertiary B

Terminal Bronchiole

Respiratory Bronchiole

alveoli

what don’t respiratory Bronchiole and alveoli have

cilia or smooth muscle

can the smooth muscle lining Bronchiole constrict

Yes -asthma

what are Alveoli:

clusters of dead end pouches for gas exchange

what is the purpose of Alveolar macrophages

cleaning

what is the purpose of Type II alveolar cells

surfactant

what is the purpose of Type I alveolar cells (simple squamous epithelial)

gas exchange

the conducting zone

area only for airflow not gas exchange

respiratory zone

area gas exchange

characteristics of bronchi and bronchiole

cartilage, yes or no

type of epithelium

blood flow

alveoli, yes or no

how much air can a fully inflated lung contain

5-6 liters

The surface area of the 150 million tiny alveoli in

each lung is about

75 meters

in a single lung, The surface area of the capillaries that sit underneath the alveoli is about

60 meters

the volume of blood in these alveolar capillaries at rest is about

70 ml

the volume of blood in these alveolar capillaries when exercising rigorously is about

200 ml

how fast must blood move through

capillaries

fast

how fast must gas exchange be

fast

how many pleural cavities do you have in your thorax

2

what causes asthma

The smooth muscle lining Bronchiole can constrict

bronchi characteristics

cartilage

>1mm

pseudostratified columnar

blood supply bronchial

no alveoli

Terminal bronchioles

no cartilage

<1mm

cuboidal

bloody supply bronchial

no alveoli

respiratory bronchioles

no cartilage

<1mm

cuboidal

bloody supply pulmonary

alveoli

transit time across the alveoli is______ seconds or less

0.75 secs

Pneumothorax:

a collection of air outside the lung but within the pleural cavity.

(if pleural cavity loses its vacuum, the lung collapses and gas exchange to blood stops)

Why do right and left lung lobes have different sizes

The right lung is shorter, because the liver sits high, tucked under the ribcase, but it is broader than the left.

The left lung is smaller because of the space taken up by the heart

Why do aspirated objects/obstructions affect the right side more often than the left?

it is wider

The respiratory system is rich in

elastin and cartilage

Why is elastin so important for the respiratory system

– It stretches and stretches back!

– Located in lung tissue and thoracic wall

is Inhalation active or passive

active

is exhalation active or passive

passive

Barrel Chest:

sign of loss of elastin

Emphysema/cigarette smoke/ alpha-1-antitrypsin/ all cause

loss of elastin

Hyalin Rings are where

trachea and bronchi of lung

what do Cartilagenous rings do

prop airways open and keep airways from collapsing when you inhale

what do Smooth muscles in airways do

lets you control tune diameter/airflow

what helps prevent airway collapse when you

INSPIRE!

Cartilaginous hyalin rings

what causes the lung to collapse passively

Elastin

what causes Asthma

trachealis and other airway smooth muscle cells constrict in

response to irritants, this increases airway resistance.

Changes in resistance are most pronounced when the what constrict.

bronchioles

Cilia

tiny “hair-like” structures that carry mucus, bacteria, pollen, dust and other potentially harmful material (caught in mucus) up and out

to the glottis.

cilia do not extend into the what

alveolus/terminal bronchiole

cilia can be destroyed by what?

smoke

Lungs move and circulate air to what

maximize alveolar gas exchange

where are acute effects of asthma found

all three Bronchi

how gas exchange happens in Terminal Bronchioles and Respiratory Bronchioles

hardly any

when air isnt in the alveoli, the air sits in what can be called a

“dead space”

what is a “dead space”

significant gas exchange can’t occur here

(These dead spaces should never collapse)

You CAN inhale air and get no gas exchange to the blood because of what

collapsed bronchioles due to asthma

what length are terminal and respiratory bronchioles have

very short lengths that terminate in the blind alveolar sacs.

alveolar sacs are richly supplied

with what?

capillary beds for gas transfer to/from blood.

where does gas exchange with blood occur

Alveoli

where do cartilaginous rings end

Tertiary Bronchi

where is dead space located

above Terminal Bronchiole

how much gas exhcange happen in the Respiratory Bronchiole (Alveolar Ducts):

just a small amount

Describe carbon dioxide and oxygen transfer to/from blood/air

as oxygen in the lungs leaves and goes into the blood, co2 leaves the blood and enters the lungs

Distance from alveolar surface to capillary is a function of..

cells in between and the depth of fluids lining the alveolus

Distance from Alveolus to hemoglobin in a erythrocyte in a Capillary

0.5

what differs from Smoker vs Non-smoker

difference in HEMATOCRIT

How many plasma membranes must oxygen pass through before reaching hemoglobin

5

Gas Diffusion REQUIRES what?

a thin film of water on alveolar surface

Can oxygen or carbon dioxide directly dissolve in water!

a very little amount can

to improve solubility, oxygen is carried by

4 subunits of hemoglobin

to improve solubility, Carbon dioxide is converted to

bicarbonate

Wandering Macrophage (ma)

destroy bacteria and cleans the surface

surfactants and mucus are important for what

air cleaning, optimal gas exchange and lowering internal surface tension.

Alveolar macrophages

specialized monocytes (macrophages) actually leave the blood and patrol the alveolar surface against bacteria and unwanted items.

visceral membrane covers what

lung

parietal membrane covers what

rib cage

Visceral and Parietal Pleural membranes allow what

serosa

Pleural Fluid Function

Friction

Pressure gradient/maintains suction

Pulmonary Cavity:

air space inside airways (bronchi-alveoli)

Inspiration and Expiration require what

pressure gradients

respiratory pressure at rest

respiratory pressure during inhaltion

volume goes up pressure goes down.

respiratory pressure during exhalation

pressure goes up volume goes down

BOYLE’S GAS LAW

ressure is inversely proportional to volume if temp.

so as pressure goes up volume goes down

and as volume goes up pressure goes down.

1 Atmosphere is equal to:

760

Pressure inside an alveoli

Intrapulmonary Pressure

Pressure inside pleura:

Intrapleural Pressure

Transpulmonary Pressure-

determines if lung inflates (-mmHg) or deflates (+mmHg)

as Transpulmonary Pressure decreases the lungs

inflate

as Transpulmonary Pressure increases the lungs

deflate

Inspiration is caused by

diaphragm contracts and pulls down and/or External intercostal muscles contract

+Volume and - Pressure (↑Vol ↓Press) ....air sucked into lung