Respiratory System [Chapter 22]

What is respiration?

Processes that provide tissues with O2 and rid them of CO2

What is pulmonary ventilation?

movement of air into and out of the lungs

What is external respiration?

gas exchange between lungs and blood

What is gas transport

Blood carries hasses to and from tissues

What is internal respiration

exchange of gases between blood and body cells

What is the upper respiratory tract?

Nares, Nasal cavity, Paranasal sinuses, Pharynx [naso, oro, larygo]

What is the purpose of the upper respiratory tract

warms, humidifies, filters, and transports air

What is the nares

nostrils

Nares (Picture)

What important structures and processes are within the nasal cavities

Olfactory mucosa for smell
Conchae provide large surface area
Ciliated cells move mucus posteriorly

What is the function of paranasal sinuses

weight reduction and sound resonance

Nasal cavity (Picture)

What is the pharynx

throat

What is the importance structures and functions of the Nasopharynx

Air passageway
Pharyngeal and tubal tonsils
Pharyngotympanic tubes, Middle war pressure equalization

What is the important structures and functions of the Oropharynx

Food and air passageway
Oral cavity meets nasopharynx
Palatine and lingual tonsils

What is the important structures and functions of the Laryngopharynx

Food and air
extends down esophagus a little

Nasopharynx (Picture)

Oropharynx (Picture)

Laryngopharynx (Picture)

What is the Lower Respiratory System

Conducting and Respiratory zone
Larynx, Trachea, Bronchioles

What is the conducting zone

no gas exchange, from nares to terminal bronchioles

What is the respiratory zone

gas exchange occurrence, Respiratory bronchioles, Alveolar ducts, Alveoli

What is the larynx

Voice box and air passageway
Made of eight hyaline cartilages

Larynx (Picture)

epiglottis (Picture)

What is the epiglottis

Made of elastic cartilage
Covers glottis when swallowing, directs food into the esophagus

What is the trachea

Windpipe, extends from larynx to bronchi
Has hyaline cartilage rings, ciliated epithelium which move mucus superiorly

trachea (Picture)

What is the bronchial tree

a branching system of air tubes in each lung, bronchioles and subdivisions

What are the bronchi

The two tubes which split from the trachea and carry air into the lungs

What are the bronchioles

Below 1 mm diameter
Airways in the lungs that lead from the bronchi to the alveoli.

What are the Terminal Bronchioles

Below 0.5 mm diameter
end of conducting zone, smallest of the bronchi

What happens as you decrease down the bronchioles

Cartilage decreases, Smooth muscle increases, Ciliated cells decrease

What is the respiratory membrane

The thin membrane of alveoli where gas exchange takes place
0.5 micrometers thick, Simple Squamous epithelium

What are Alveolar cells

Type I, Type II, and macrophages

What are Type 1 Alveolar cells

simple squamous cells where gas exchange occurs

What are Type II Alveolar cells

secrete surfactant

What is pulmonary circulation?

circulation between heart and lungs

What is Bronchial circulation

bronchial arteries provide oxygenated blood to lung tissue

What is the pulmonary plexus

at the root of each lung- both efferent and afferent autonomic fibers- formed by sympathetic trunks and vagus nerves

What does the sympathetic system do within the lungs

Dilation of bronchi

What does parasympathetic system do within the lungs

constriction

What is the visceral pleura?

serous membrane that covers lungs

What is the parietal pleura?

lines the walls of the thoracic cavity

What is Atmospheric pressure

760 mmHg

What is intrpulmonary pressure?

760 mmHg when airway is open

What is intrapleural pressure

4 mmHg or less

What is transpulmonary pressure?

Difference between the intrapulmonary and intrapleural pressures
P pul - P pip =4 mmHg

What is Boyle's Law?

P1V1=P2V2

Is inspiration active or passive?

active

Is expiration active or paassive?

passive

What muscles facilitate inspiration

Diaphragm and External intercostals

What is negative pressure inspiration

lower pressure inside lungs providing the power needed

What muscles facilitate expiration

internal intercostals, and abdominal muscles

What is airway resistance

F=DeltaP/R
Delta P is the most important factor

What is Alveolar surface tension

liquid molecules lining lungs attract each other, surfactant counters it

What is lung compliance?

It is the stretchability of our lungs. The more the lungs can expand the more the compliance.

What physical factors affect pulmonary ventilation

Airway resistance, Alveolar surface tension, Lung compliance

What is anatomical dead space?

The amount of gas that stays in the pipes, the conduction zone.

What is alveolar dead space?

non-functional alveoli due to collapse or obstruction

What is total dead space

sum of anatomical and alveolar dead space

What is alveolar ventilation?

6 L/min at rest
up to 200 L/min with exercise

What is Dalton's Law?

The total pressure of a mixture is equal to the sum of the partial pressures of gasses

What is Henry's Law?

gases will dissolve into a liquid in proportion to their partial pressures

What is ventilation-perfusion coupling?

matching of alveolar ventilation with pulmonary blood perfusion

How much of oxygen is carried by hemoglobin

98.5%

How much O2 can hemoglobin carry?

4 O2 molecules

What is the Bohr effect?

conditions in the body tissues enhance o2 unloading

How much COs in released by cells

200 ml/min

How much CO2 is dissolved in plasma?

7-10%

How much CO2 is bound to hemoglobin?

20%

How much CO2 is a bicarbonate

70%

What is the Haldane effect?

The lower the PO2 and hemoglobin saturation with O2, the more CO2 can be carried in the blood.

What is ischemic

impaired circulation

What is histotoxic hypoxia?

Cells cant absorb O2, as in from some poisons

What is Hypoxemic hypoxia

Inadequate O2 reaching blood from lungs

What part of the brain affects breathing

Medullary respiratory centers, which stimulate phrenic/intercostal nerves

What is eupnea?

normal quiet breathing of 12 breather/min

What chemical factors influence breathing rate

PCO2, PO2, And arterial pH

What is PO2

partial pressure of oxygen

What is hypercapnia

excess carbon dioxide in the blood

What is hypocapnia?

low CO2 in blood

What Are Chronic Obstructive Pulmonary Diseases (COPD)

Emphysema and Chronic Bronchitis

What is Emphysema

Blown out Alveoli and reduced surface area

What is chronic bronchitis?

Excessive mucus production

What is Asthma

chronic inflammatory disorder of the airways

What are Tubercles

lung nodules that can bust and spread bacteria