CH 20 & 23

Describe the components of the upper respiratory system and their functions

nose, nasal cavity, sinuse, Pharynx

The nasal cavity

The nasal septum

*Divides nasal cavity into left and right, provides sense of smell, cleans and moisten the nasal cavity, Mucus secretions from paranasal sinus and tears. Divides nasal cavity into left and right provides sense of smell, cleans and moisten the nasal cavity, Mucus secretions from paranasal sinus (air flow)

Meatuses

Are constricted passageways that produce air turbulence

*Nasal mucosa also helps with humidification of air

-The palates, hard palate, forms floor of nasal cavity. separates nasal and oral cavities

Soft palate

-extends posterior to hard palate

-divides superior nasopharynx from lower pharynx

The Pharynx

A chamber shared by digestive and respiratoy systems, extends from internal nares to entrances to larynx and esophagus *divided into three parts

1.nasopharynx-superior portion of pharynx (contains pharyngeal tonsil and opening to left and right auditory tubes)

2.The oropharynx- Middle portion of Pharynx

-communicates with oral cavity

Describe the components of the lower respiratory system and their functions

The laryngopharynx- Inferior portion of pharynx

Extends from hyoid bone to entrance of larynx esophagus

Cartilages of LARYNX

3 large, unpaired cartilages from the larynx

1.Thyroid cartilage

2. Cricoid cartilage- hyaline cartilage, Forms posterior portion of larynx, Ligaments attach to first tracheal cartilage, Articulates with arytenoid cartilgaes

3. Epiglottis- Elastic cartilage, Ligaments attach to thyroid cartilag and hyoid bone

4. Cartilage functions -thyroid and cricord cartilgaes support and prtect

   *The glottis

   *The entrance to trachea, during swallowing, the larynx is elevated, the epiglottis folds back over glottis, prevent entry of food and liquids into repiratory tract

The Larynx contains 3 pairs of smaller Hyaline cartilages

1.Arytenoid cartilages

2.Corniculate cartilgaes

3.Cuneiform cartilgaes

Corniculate and arytenoid cartilgaes funtions in:

opening and closing of glottis, production of sound

The Trachea

Extends from the cricoid cartilage into mediastinum,

where it branches into right and left pulmonary bronchi

-The tracheal cartilages (15-20 tracheal cartilages)

*Strengthen and protect airway, Discontinous where trachea contacts esophagus

The primary Bronchi

To allow esophagus to expand when it contains food

Right and left Primary Bronchi

separated by an internal ridge, The right primary Bronchus is larger in diameter than the left primary bronchus

Hilum

Where pulmonary nerves, blood vessels, lymphatics enter lung

*Anchored in meshwork of connective tissue

The thyroid cartilage

Forms anterior and lateral walls of larynx, anterior surface callled laryngeal prominence, or Adam’s apple, ligaments attach to hyoid bone, epiglottis, and laryngeal carillages

What is the difference between respiratory v.s. conducting portion of the respiratory

The respiratory tract- consists of a conducting portion Description: From nasal cavity to the terminal brochioles

Conducting portion of the respiratory system

This is where gaseous exchange takes places, Involves respiratory bronchioles and alveoli

Describe the structure of the lungs

The lungs are in left and right plural cavities

Lobes and surfaces of the lung

The right lung has three lobes (superior, middle, and inferior)

*seperated by horizontal and oblique fissures

The left lung has two lobes

Superior and inferior, seperated by an oblique fissure

Right lung is wider

Left lung is longer

The bronchi has bronchial tree

is formed by the primary bronchi and their branches

Primary bronchus

branches to form secondary bronchi, one secondary bronchus goes to each lobe

Secondary bronchi

branch to form tertiary bronchi

bronchial strucutre

The walls of primary, secondary, and tertiary bronchi, contain progessively less cartilages and more smooth muslce, increased smooth muscle tension affects airway constriction and resistance

The bronchioles

each tertiary bronchus branches into multiple bronchioles, bronchioles branch into terminal bronchioles, one tertiary bronchus form about 6500 terminal bronchioles, each terminal bronchiole branches to form several respiratory bornchioles, where gas exchange takes place

Bronchiole structure

bronchioles, have no cartilage, are dominated by smooth muscle

Describe the function of the alveoli

air filled pockets with lungs, where all gas exchange takes place, a

Alveolar epithelium

consists of simple squamous epithelium, consists of simple squamous epithelium, delicate type 1 pnemocytes patrolled by alveolar macropahages? function Gaseous exchange Contains type ll pneumocytes (septal cells) that produce surfactant

Surfactant

an oily secretion with lipids and proteins function? Redudces surface tension

The action of breathing

1. Diaphragm relaxes- becomes dome shaped- make thoracic cavity smalller

2. External intercostal muscles relax- will cause the rib cage to move down and inwards, Air will move from high pressure (inside thoracic cavity) to lower pressure which is outside = Exhalation The thoracic cage gets smaller therefore increasing the pressre

How is Hemoglobin binding affected by temperature and Ph?

Hemoglobin and Ph and Temperature

Bohr effect is the result of pH on hemoglobin- saturation with H2O

*Produces carbonic acid

*Dissociates into hydrogen ion and bicarbonate ion

What is chloride shift? Hydrogen ions diffuse of RBC, lowering pH

The oxygen- Hemoglobin saturation curve

*Is standardized for normal blood

when ph. drops or temperature rises

*More oxygen is released

when pH rises or temperature drops: Less oxygen is released

CH 20.

The conducting system of the heart/impulse conduction through the heart

1. Sa node activity and atrial activation being

2. Stimulus spreads across the atrial surfaces and reaches the AV node

3. There is a 100-msec delay at the AV node. Atrial contraction begins

4. The impulse travels along the interventricular septum within the AV bundle and the bundle branches to the Purkinje fibers and, by the moderator band, to the papillary muscle of the right ventricle

5. The impulse is distributed by Purnje fibers and relayed throughout the ventricular myocardium. Atrial contraction is completed, and ventricular contraction begins

The important landmarks of ECG/EKG

P wave- atria depolarize- Atrial contraction, QRS complete

*ventricles depolariz- ventricles contraction

T wave- ventricles repolarize- ventricles relax, Time intervals between ECG waves

P-R interval

*From start of atrial depolarization

*To start of QRS complex

Q-t interval

*From ventricular depolarization

* To ventricular repolarization

*Ventricular contraction begins

Can you tell the difference between the 4 cardiac arrhythmias that were discussed in class

Pac

Premature atrial contractions

Often occur in healthy individuals. In a PAC, the normal atrial rhythm is momentarily interrupted by a Suprise atrial contraction.

 the normal atrial rhythm is momentarily interrupted by a surprise atrial contraction. Stres, caffeine, and various drugs  may increase the incidence of PAC’s presumbaly by increasing the permebilities of the SA peacemakers. The impulse spreads along the conduction pathway and a normal ventricular contraction follows the atrial beat

Atrial Fibrillation (AP)

 During AP the impulses move over the atrial surface at rates of perhaps 500 beats per minute. The atrial wall quivers instead of producing an organized contraction. The ventricular rate cannot follow the atrial rate and may remain within normal limits. Even though the atria are now nonfunctional. Their contribution to ventricular end- diastolic volume is so small that the condition may go unnoticed in older individuals

VT- Ventricular Tachycardia

 is defined as four or more PVC’S without intervening normal bats. It is also known as Vt or V-tach multiple PVC’s and Vt may indicate that serious cardiac problems exist

Ventricular Fibrillation- VF

VF is responsible for the condition known as cardiac arrest. VF is rapidly fatal because the ventricles quiver and stop pumping blood

Brachycardia

Slow heart rate

Tachycardia

Abnormally fast heart rate

Cardiovascular system

1.Right atrium- receives deoxygenated blood from systemic circuit

2. Right ventricle- Pump blood to the pulmonary circuit

3. Left atrium- Collects blood to the pulmonary circuit

4. left ventricle- Pumps oxygenated blood to the systemic circuit

Flow of blood entering the systemic circulation and pulmonary circulation

Blood gathers into left and right pulmonary veins

Pulmonary veins deliver to left atrium, blood from left atrium passes to left ventricle through left atrioventricular valve,

The left ventricle blood leaves left ventricle through aortic valve into ascending aorta, ascending aorta turns and becomes descending aorta