(Exam 3) Pt. 4 Respiratory System Structure & Function

Purpose of respiratory system:

• [….]

  • Ventilation

  • Exchange of O2 and CO2 in the lungs

• [….]

  • O2 utilization and CO2 production by the tissues

  • Break down food stuff to synthesize ADP aerobically

• purpose of the respiratory system during exercise

  • Gas exchange between the [….]

  • Regulation of […] during exercise

• Pulmonary respiration

• Cellular respiration

• environment and the body

• acid-based balance

Respiratory system-big picture:

• Ventilation

  • Mechanical process of moving air into and out of lungs

    • inspiratory muscles need to […]

    • the main muscle is the […] muscle

  • when we breathe in; we want to decrease [….] pressure

    •   Intra thoracic pressure must fall below atmospheric pressure

    • Atmospheric pressure is [….], because gas is moving in from an area of higher pressure to an area of lower pressure.

    • How do we do that by expanding lung volume.

    • increase the volume intrathoracic pressure drops, your atmosphere of pressure; allows airs come into the lungs.

• Diffusion

  • random movement of molecules from an area of […] concentration to an area of […] concentration

• contract

• diaphragm

• intra-thoracic

• constant

• high

• lower

Exchange of respiratory gases between the atmosphere and the cells:

• Process 1:

• Pulmonary ventilation

  • movement of respiratory gases between the atmosphere and the lungs and specifically the gas exchange region of the lungs (Alveolar region)

Exchange of respiratory gases between the atmosphere and the cells:

• Process 2:

• Alveolar gas exchange:

  • Deoxygenated blood

  • heart pumps deoxygenated blood from right ventricle to go to the lungs through pulmonary veins

  • pulmonary arteries carries oxygenated blood

  • blood reaches the lungs and the alveoli; blood will drop-off CO2 and receive oxygen; It will become oxygenated.

Exchange of respiratory gases between the atmosphere and the cells:

• Process 3:

• Gas transport:

  • then it will be […] so we have systemic circulation, gas transport

  • blood includes […]

• transported

• oxygenated and CO2

Exchange of respiratory gases between the atmosphere and the cells:

Process 4:

• Systemic gas exchange:

  • we have gas exchange between […[

  • what happens at […]; blood will drop off oxygen molecules, so the […] will receive oxygen, and it will drop off CO2

  • Deoxygenated blood will return to the heart on […] side of the heart and will send blood back to […] and […].

• bloodstream, cells and different tissues

• capillary bed

• tissue

• right

• lungs

• repeat the processes.

• Lungs are enclosed by a set of membranes called pleura

• Pleura has 2 layers:

• [….] pleura:

  • Lines the outer surface of the lung

• […] pleura:

  • That lines the thoracic lung

• between the layers we have […]:

  • within it we have pleura fluid that acts at a lubricant that reduces friction between between the visceral and parietal.

• Visceral

• Parietal

• pleural cavity

The Conducting Zone:

• Air enters the [….] from the pharynx

• For gas to enter or leave the trachea, it must pass though the […]

• The trachea branches into two primary […] (right and left)

• The bronchial tree branches several more times before reaching the bronchioles (small branches of the bronchial tree)

• It […] the air as it moves to the lung.

• The bronchioles branch several more times before they become the […] leading to the alveolar sacs and respiratory zone of the lung.

• trachea

• epiglottis

• bronchi

• filters and humidifies

• alveolar ducts

The Conducting Zone:

• epiglottis:

  • epiglottis is [….[

  • connected to the [….[

  • main function of epiglottis:

  • tissue made of [….]

  • it folds back over the glottis when we swallow and then prevents liquid or food from going in the [….].

  • Prevents liquid and food from going to the lungs

• cartilaginous blood

• thyroid cartilages

• cartilage flap

• respiratory system

The respiratory zone:

Alveolar ducts and alveoli:

• Each lung has about 150 million alveoli:

  • region of the lungs where [….] takes place

• Extensive network of […] surrounds each alveolus:

  • Capillaries drop off […] and pick up […]

• […] tissue surrounds each alveolus:

  • maintains the shape and position of each alveolus during inhalation and exhalation

  • maintain shape and provides structural support.

• gas exchange

• capillaries

• carbon dioxide

• oxygen

• Elastic

Gas exchange across alveolar wall into capillaries:

• Pulmonary arteries transport CO2 to the […] capillaries

• […] leaves the capillaries and enters the alveolar sacs

• […] leaves the alveolar sacs and enters the capillaries

• O2 enters the […] and returns to the heart to be pumped to all parts of the body

• alveolar

• CO2

• O2

• pulmonary veins

Mechanics of breathing:

• Pressure in the atmosphere is […]; we know that gas is moved from an area of high pressure to an area of low pressure.

• constant

Mechanics of breathing:

• Pressure differences between intrapulmonary pressure and atmospheric pressure

  • To bring air into our lungs, we need to […] intra-thoracic pressure

  • The pressure must fall below the […] pressure.

  • Increase pressure by […] volume.

• decrease

• atmospheric

• increasing

Mechanics of breathing:

• Inspiration occurs when volume of lung [….]

  o   Create […] intrathoracic pressure

  o   Increase anterior-posterior, lateral, & vertical diameters and volume

  o   Using […] , intercostals (other accessory muscles)

  o   Diaphragm will contract and move down and at the same time the […] elevate the rib cage. So, we expand thoracic volume.

  o   It allows air to come in.

• increases

• negative

• Diaphragm

• external intercostal

Mechanics of breathing:

• Expiration occurs when volume of lung […]

  • Breathing out the diaphragm will […], the internal intercostals […] the rib cage, and we now increase in intra thoracic volume.

  • And that increases intrathoracic pressure above atmospheric pressure.

• Movement of the chest wall resulting in lung volume changes occurs due to […]

• decreases

• relax and it moves out

• depress

• contraction of respiratory muscles

Respiratory Muscles and Pulmonary Ventilation:

• Diaphragm

  • [….] (lowers) to cause inhalation

  • […] (raises) to cause exhalation

• External intercostals

  • Elevate the ribs to aid in […]

• Internal intercostals

  • Depress the ribs to aid in [….]

• Contracts

• Relaxes

• inhalation

• exhalation

Airway resistance:

Airflow depends on:

• Pressure difference between two ends of airway

• Resistance of airways

Airway resistance is influenced by the […] of the airway

• […] airways increase resistance to flow

• […]diameter the greater the resistance.

• diameter

• Smaller

• Smaller

Pulmonary ventilation:

• Pulmonary ventilation = movement of gas into and out of the lungs

  • V = volume of gas

  • Dot (. ) over V means per unit of time (usually per minute)

Alveolar ventilation:

• Pulmonary Ventilation includes both […]

• Dead space ventilation (VD) refers to the portion of tidal volume (VT ) that does not reach the […]

• Alveolar ventilation (VA) refers to the portion of tidal volume that reaches the [….]

• dead space and alveolar ventilation

• alveolar compartment

Spirometry used to measure lung volumes:

-   Forced expiratory volume during the […]:

o   Volume of air that an individual can forcibly expel during the first second following maximal inhalation.

-    […] (FVC):

o   Total volume of air that an individual can exhale during a forced breath.

§  Total volume of air that the induvial can exhale during forced breath.

• first second (FEV1)

• Forced vital capacity

Partial pressure of gases:

-     […]

o   The total pressure of a gas mixture is equal to the sum of the pressure that each gas would exert independently.

• Dalton’s Law

Diffusion of gases:

[…] law of diffusion

• Describes what VO2 is

• The rate of gas transfer (V gas) is proportional to:

  • the […]

  • the diffusion […]of the gas (i.e., how easily a molecule diffuses)

  • the difference in the partial pressure of the gas on the two sides of the tissue

  • inversely proportional to the […]

• Fick’ s

• tissue area

• coefficient

• thickness.

O2 and CO2 transport in blood:

• 99% of O2 is transported bound to […]

o   [….]: Hb bound to O2

o   […]: Hb not bound to O2

• Amount of O2 that can be transported per unit volume of blood is dependent on the Hb concentration

o   Each gram of Hb can transport 1.34 ml O2

o   Oxygen content of blood (100% Hb saturation)**

• Males: 150 g Hb/L blood

o   200 ml

• Females: 130 g Hb/L blood

o   174.2 ml

• hemoglobin (Hb)

• Oxyhemoglobin

• Deoxyhemoglobin

Oxyhemoglobin dissociation curve:

-  Deoxyhemoglobin + O2 « Oxyhemoglobin

-  Direction of reaction depends on

o   […] of the blood

o   Affinity between Hb and O2

-   At the lung

o   [….] = formation of oxyhemoglobin

-   At the tissues

o[….] = release of O2 to tissues

• PO2

• High PO2

• Low PO2

Effect of pH, temperature on oxyhemoglobin dissociation curve:

-          pH

o   Decreased pH […] Hb-O2 affinity

o   Favors […] of O2 to the tissues

-          Temperature

o   […] blood temperature lowers Hb-O2 affinity

o   Favors […] of O2 to the tissues

• lowers

• unloading

• Increased

• unloading

O2 transport in the muscle:

-          We have [….] in blood stream, but not muscle in muscle we have […].

-          Myoglobin (Mb)

o   Shuttles O2 from the cell membrane to the mitochondria

-          Mb has a […] affinity for O2 than hemoglobin

o   Binds O2 at a very low PO2

o   Allow Mb to store O2

§  Buffers muscle O2 needs at onset of exercise until cardiopulmonary system increases O2 delivery to muscle.

• hemoglobin

• myoglobin

• higher

CO2 transport in blood:

-  CO2 transported in blood in three ways

o   Dissolved in […] (10%)

o   Bound to […] (20%)

o   […] (70%)

o   When CO2 mixed with water it forms carbonic acids and carbonic acids clean itself into hydrogen ion and bicarbonate.

• plasma

• Hb

• Bicarbonate

Ventilation and acid-base balance:

-  Increased […] in blood or body fluids increases hydrogen ion accumulation, which decreases pH.

-  Removal of […] from blood or body fluids decreases hydrogen ion concentration, while increases pH.

- […] ventilation results in CO2 exhalation

o   Reduces H+ concentration, ↑pH

-  […] ventilation results in buildup of CO2

o   Increases H+ concentration, ↓pH

• CO2 (2x)

• Increased

• Decreased