Unit 3 Vascular Physiology (BIOL 460)

The exchange of oxygen and carbon dioxide between tissue cells and the external environment

external respiration

Bronchioles are made of ___ (cartilage/smooth muscle)

smooth muscle

Bronchioles ___ (are/are not) innervated by neurons

are

Bronchioles ___ (are/are not) responsive to hormones and chemicals in their microenvironments

are

Bronchioles regulate the flow of air passing through them to and from the ___

alveoli

Bronchioles regulate air flow by ___ and ___

bronchoconstricting and bronchodilating

Tiny, grape-like air sacs at the end of the bronchioles in the lungs

alveoli

Tiny, thin-walled airway branches in the lungs that lead from the bronchi to the alveoli

bronchioles

Type I alveolar cells are incredibly ___ (thin/thick) and so are highly optimized for gas exchange

thin

Type II alveolar cells secrete pulmonary ___ onto the surface of the alveolar epithelium, the type I cells

surfactant

Muscle ___ (is/is not) present in the alveolar walls

is not

The diaphragm is composed of ___ muscle

skeletal

The diaphragm is controlled by ___ (somatic/autonomic) neurons and is therefore (voluntary/involuntary)

somatic, voluntary

One ___sac surround each lung

pleural

The space inside the pleural sac is called the plural ___

cavity

Inside the pleural cavity is a small amount of lubricating ___ fluid

intrapleural

Each lung is ___ (in a/surrounded by) a pleural cavity

surrounded by

The pressure pushing on your skin and body

atmospheric or barometric pressure

The pressure inside the alveoli

intra-alveolar pressure

The pressure in the pleural cavity

intrapleural pressure

Intra-alveolar pressure regularly regulates ___ pressure

barometric

The thoracic cavity is ___ (smaller/larger) than your unstretched lungs

larger

What fluid cohesiveness holds the lungs to the thoracic cavity

intrapleural fluid

The thoracic wall is also called the

ribcage

During development, the thoracic wall grows ___ (slower/faster) than the lungs

faster

The lungs are elastic, like a stretched balloon that wants to shrink back to its starting shape. This creates a ___ between the thoracic cavity and lungs

vacuum

The pressure within the pleural cavity is ___ (lower/higher) than both the air inside the lungs and the air outside the body

lower

The pleural cavity is the "low pressure zone" (the vacuum), so the higher pressure on either side of it always tries to move ___ (toward/away from) it

toward

When air enters the pleural cavity, it is called

pneumothorax

The lung collapses when the ___ ___ ___ is lost

transmural pressure gradient

Pneumothorax occurs because of a puncture through the ___ wall or a hole in the ___

chest, lung

What respiratory pressure can be directly changed

intra-alveolar pressure

Pressure and volume have a(n) ___ (direct/inverse) relationship at a constant temperature

inverse

To breathe in, we ___ (increase/decrease) the intra-alveolar pressure by ___ (increasing/decreasing) the alveolar volume

decrease, increasing

To breathe out, we ___ (increase/decrease) the intra-alveolar pressure by ___ (increasing/decreasing) the alveolar volume

increase, decreasing

___ muscle moves the thoracic wall to change the volume of the thoracic cavity

skeletal

Increasing the alveolar volume ___ (increases/decreases) the intra-alveolar pressure

decreases

Decreasing the alveolar volume causes ___ (more/less) collisions to occur between air molecules

more

Respiratory Physiology is dependent upon 3 steps:

ventilation, gas exchange, and gas transport

The physical movement of air into and out of the respiratory tract

pulmonary ventilation

Inhalation always requires ___

energy

The lungs move and expand with the ___ ___

thoracic cavity

The lungs themselves ___ (are/are not) muscular

are not

When blood fills the thoracic cavity, it’s called

hemothorax

The muscle that moves down and flattens out to increase the volume inside the thoracic cavity so you can inhale

diaphragm

When you breathe in your diaphragm goes ___ (down/up)

down

When you breathe out your diaphragm goes ___ (down/up)

up

The muscles between the ribs which pull the ribcage up and out to allow you to inhale

external intercostal

When you breathe in, intra-alveolar pressure ___ (increases/decreases)

decreases

When you breathe out, intra-alveolar pressure ___ (increases/decreases)

increases

Air ___ (does/does not) inflate the lungs

does not

The only time air inflates the lungs is during

CPR

In relaxed breathing, exhalation is ___ (active/passive)

passive

Relaxed exhalation is passive because of the ___ ___ of the thoracic cavity and alveoli

elastic recoil

Forced exhalation is moved by the ___ ___ muscles contracting and pulling the ribs down and in

internal intercostal

Forced exhalation is also moved by the ___ ___ along with the internal intercostal muscles

rectus abdominis

Diameter has a(n) ___ (direct/inverse) relationship to resistance

inverse

COPD stands for

chronic obstructive pulmonary disorder

___ is the effort required to stretch the lungs

compliance

___ is how readily the lungs rebound after being stretched

elastic recoil

A tootsie roll has ___ (high/low) compliance and ___ (high/low) elastic recoil

high, low

A car tire has ___ (high/low) compliance and ___ (high/low) elastic recoil

low, high

The fluid inside the alveoli

surfactant

Surfactant ___ (breaks/maintains) the surface tension of water in the alveoli

breaks

Surfactant is a ___ that acts like detergent

lipid

Surfactant resists ___ (expansion/contraction)

expansion

Surfactant ___ (increases/decreases) compliance

increases

Surfactant makes breathing ___ (easier/harder)

easier

Your lungs would glue shut every time you exhale without surfactant because of ___ (high/low) surface tension

high

Premature babies often can’t breathe because of a lack of ___

surfactant

The volume of air inhaled and exhaled during a resting breath

tidal volume

The volume of additional air that can be forcibly inhaled after a normal tidal inspiration

inspiratory reserve volume

The volume of additional air that can be forcibly exhaled after a normal tidal expiration

expiratory reserve volume

The total volume that can be consciously controlled in and out of the lungs

vital capacity

TV + IRV + ERV =

vital capacity

The volume that remains in the lungs even after a maximal exhalation

residual volume

The volume of air that cannot be exhaled and prevents the lungs from collapsing

residual volume

Emphysema is when you lose elastic tissue in the alveolar walls, meaning you lose ___ ___

surface area

Gas exchange heavily depends on ___ law

Fick’s

According to Fick’s law, high surface area means ___ (high/low) diffusion

high

According to Fick’s law, thicker membranes mean ___ (high/low) diffusion

low

Pulmonary edema increases the ___ (surface area/thickness) of the respiratory membrane

thickness

Epithelial cells are designed to be ___ (thick/thin) to allow for diffusion

thin

Active transport ___ (does/does not) exist for gases

does not

The rate of diffusion is dependent on the size of the ___ gradient

pressure

The pressure of one gas has ___ (some/no) effect on the diffusion rate of another

no

The pressure (collisions) exerted by one gas in a mixture of gases

partial pressure

Pressure is all about the ___ between molecules in a chamber

collisions

Partial pressure allows us to account for different atmospheric ___

pressures

Pressure is less about the molar quantity of particles and more about the frequency of collisions which is determined by ___

volume

Partial pressure is ___ (high/low) in low atmospheric pressures

low

The higher you go in the atmosphere, the ___ (more/less) the molecules can spread out

more

The partial pressure gradient pushes oxygen from the ___ to the ___ to the ___

alveoli, blood, tissues

The partial pressure gradient pushes carbon dioxide from the ___ to the ___ to the ___

tissues, blood, alveoli

The magnitude of the partial pressure gradient of oxygen ___ (increases/decreases) as you get further into the body

decreases

Most oxygen is transported in the blood by being bound to

hemoglobin

Hemoglobin can bind how many oxygen molecules

4

___ is the primary determinant of hemoglobin saturation

oxygen

Fetal hemoglobin has a ___ (higher/lower) affinity to oxygen

higher

Hemoglobin allows the body to transport ___ (more/less) oxygen

more