respiration

respiratory system funtion

supply tissues with O2 and dispose of CO2

what is the collective process of the respiratory system?

1. pulmonary ventilation

2. external respiration

3. gas transport

4. internal respiration

respiratory zone

site of actual gas exchange within lungs

• O2 enters blood

• CO2 exits blood

conducting zone

rigid conduits for air

vibrissae

nasal hair, serves to filter air going in

boudnaries

roof: spehnoid/ethmoid

floor: maxilla, palatine, and soft palate

conchae

protrude medially and increase surface area

olfactory mucosa

on SNC w/ olfactory receptors

respiratory mucosa

if irritated, you sneeze

• defensins, lysozymes

function of conchae and mucosa

reclaiming heat and moister and filter air on the way in

description of paranasal sinuses

spaces surrounding nasal cavity

what bones are part of the paranasal sinuses

frontal, sphenoid, ethmoid, and maxillary

what are the fuctions of the paranasal sinuses?

• lighten skull

• help warm and moisten air

carina

last tracheal cartilage (last change before food enters lungs)

bronchioles

cuboidal ET, complete layer of smooth muscle and no cartilage

what vessels are associated with blood supply to lungs?

pulmonary arteries

what vessels are associated with lung tissue nourishment?

bronchial arteries

what is the order of flow in the respiratory zone?

1. terminal bronchiol

2. alveolar ducts

3. alveoli

4. 300 million alveoli (most of volume)

what composes the air blood barrier?

fused walls of alveoli and capillaries

what are characteristics of alveolar walls?

• type I cells simple squamous ET

• permit gas exchange by simple diffusion

what do type II cells secrete?

surfactant

what are four key characteristics of alveoli?

1. smooth muscle

2. elastic fibers

3. alveolar pores

4. macrophages

parietal pleura

line inside of cavity

visceral pleura

line outside of lungs

pleural space

contains fluid to allow membranes to slide past each other

pleurisy

inflammation of lining

what muscles are involved in quiet breathing?

the external intercostal muscles

what occurs during quiet breathing?

external intercostal muscles contract, elevating the ribs and moving the sternum

what occurs during labored breathing?

additional muscles contract, cuasing additional expansion of the thorax

what occurs to intrapulmonary pressure as in inhale?

intrapulmonary pressure decreases

what occurs to intrapulmonary pressure when you exhale?

intrapulmonary pressure increases

what forces are promoting lung collapse?

elasticity of lungd and surface tension of alveolar surfactant

what forces promote lung expansion?

elasticity of chest wall and low Pi

what occurs when the pressure in the lungs is greater than the pressure in the pleural space?

the pleural space acts like a vacuum and sucks the lungs open

pneumothroax

collapsed lung

daltons law

total pressure = sum (pressure of each gas)

henry’s law:

concentration of a gas in a liquid is determined by its partial pressure and its solubility

what does diffusion of gases through respiratory membrane depend upon?

• membrane thickness

• diffusion coefficient of gas

• surface area

• partial pressure differences

what effect does membrane thickness have on diffusion of gases?

the thicker, the lower the diffusion rate

what effect does diffusion coefficient of gas have on diffusion through a respiratory membrane?

measure of how easily a gas diffuses through a liquid of tissue

what effect do partial pressure differences have on diffusion through respiratory membrane?

normally, partial pressure. ofoxygen is higher in alveoli than in blood. opposite is true for CO2

what is gas exchange driven by?

pressure gradients

ventilation

amount of air reaching alveoli

ventilation perfusion coupling

tighlty regulated to maintain efficient gas exchange

what. isinternal respiration driven by?

internal respiration is driven by pressure gradients

what percentage of hemoglobin is in the O2 in the blood?

98.5%

what factors affect Hb’s affinity for O2?

1. PO2

2. temperature

3. blood pH

4. PCO2

5. BPG concentration

6. cigarette smoking

how does decrease of PO2 affect Hb?

decreased O2 decreases Hb

how does high PO2 affect Hb?

increase PO2 increases Hb

how does high temp affect Hb?

high temp lowers Hb

how does lower temp affect Hb?

lower temp increases Hb

how does low blood pH affect Hb?

lower blood ph decreases Hb

how does high pH affect Hb?

lower pH increases Hb

how does increased CO2 affect Hb?

higher CO2 decreases Hb

how does decreased CO2 affect Hb?

lowered CO2 increases Hb

how does high BPG conc affect Hb?

high BPG increases Hb

how does low BPG affect Hb?

low BPG decreases Hb

after CO2 is picked up in tissues, it is transported to the blood in what forms?

1. dissolved in plasma

2. bound to hemoglobin

3. bicarbonate ion in plasam

what are the 3 things that occur when CO2 is in the lungs?

1. bicarbonate ions move into RBCs and bind with hydrogen ions to form carbonic acid

2. carbonic acid is split by carbonic anhydrase to release carbon dioxide and water

3. CO2 diffuses from blood to alveoli

what do the dorsal groups in the medullary respiratory center stimulate?

the diaphram

what do the ventral groups in the medullary respiratory center stimulate?

the intercostal and abdominal muscles

what is the pontine respiratory grou (pneumotaxic) involved in?

switching between inspiration and expiration

what occurs to intrapulmonary pressure as lung volume increases during inspiration?

pressure inside lung decreases

what ocurs to intrapleural pressure as the chest wall expands during inspiration?

pressure becomes more negative

what are 3 homeostatic imbalances that erduce compliance?

• deformaties of thorax

• ossification of the costal cartilage

  • paralysis of intercostal muscles

what occurs when vital capacity increases in athletic training?

residual volume decreases slightly

what occurs at maximal exercise?

tidal volume and minute ventialtion increases

what occurs to gas exchange during athletic training?

gas exchange between albeoli and blood increases at maximal exercise

what occurs to alveolar ventilation during athletic training?

alveolar ventilation increases

what does increased cardiovascular efficiency lead to in athletic training?

it leads to greater blood flow through the lung

what occurs to vital capacity and maximum minute ventilation in aging?

they both decrease

what occurs to residual volume and dead space in aging?

it increases