Chapter 13: - PowerPoint Presentation

Slide1

Chapter 13:The Respiratory SystemSlide2

Organs

Nose

Pharynx

LarynxTracheaBronchiLungsSlide3

Functions

Gas exchanges between the blood and

environment

Occurs in the alveoli of the lungsPassageways to the lungs purify, humidify, and warm the incoming airSlide4

The Nose

Only externally visible part of the respiratory system

Air enters the nose through the external nostrils (

nares)Interior of the nose consists of a nasal cavity divided by a nasal septumSlide5

Inside the nasal cavity:

Olfactory

receptors

in mucosa on superior surface for sense of smellRespiratory mucosa everywhere else produces sticky mucus

Moisten air

Trap incoming foreign

particles

Cilia = tiny hair-like structures that move contaminated mucus towards the pharynx where it is swallowed and digested by stomach juices

Projections called conchae on lateral walls

Increase surface area & air turbulenceSlide6

Figure 13.2Slide7

The nasal cavity is separated from the oral cavity by the palate

Anterior

part = hard

palate (bone)Posterior part = soft palate (muscle)Slide8

Paranasal Sinuses

Cavities within bones surrounding the nasal

cavity

Located in the following bones:

Frontal

Sphenoid

Ethmoid

Maxillary

Functions:

Lighten the skull

Act as resonance chambers for speech

Produce mucus Slide9

Pharynx (Throat)

Muscular passage from nasal cavity to larynx

Three

regions from superior to inferior:Nasopharynx

Oropharynx

Laryngopharynx

P

assageways

for air and foodSlide10

Pharyngotympanic tubes

that drain middle ear open

into the

nasopharynxEar infections may follow sore throatTonsils:Pharyngeal tonsil (adenoids) in the

nasopharynx

Palatine tonsils

in

the

oropharynx

Lingual tonsils

at

the base of the tongueSlide11

Figure 13.2Slide12

Larynx (Voice Box)

Function:

Routes

air and food into proper channelsPlays a role in speechStructure:E

ight

rigid hyaline

cartilages

Thyroid cartilage is largest = Adam’s apple

Epiglottis =spoon-shaped

flap of elastic

cartilage

Rises to covers larynx when you swallow so that liquid and food go to the esophagus instead of airway

Vocal folds (aka true vocal cords)

Vibrate with expelled air to create sound

Glottis = opening between vocal cordsSlide13

Anterior View of Larynx

Posterior View of Larynx

http://www.youtube.com/watch?v=QvGYvK6qScESlide14

Upper Respiratory Tract: Larynx

Figure 13.2

http://www.youtube.com/watch?v=9MDn5GgyxyU&feature=relatedSlide15

Trachea (Windpipe)

4 inch long

tube that connects larynx with bronchi

Walls are reinforced with C-shaped hyaline cartilage Lined with ciliated mucosaBeat continuously in the opposite direction of incoming air

Expel mucus loaded with dust and other debris away from lungsSlide16

Trachea (Windpipe)

Figure 13.3aSlide17

Trachea (Windpipe)

Figure 13.3b

The yellow structures are cilia. The orange structures are goblet cells that secrete mucus and have

microvilli

. Slide18

Main (Primary) Bronchi

Formed by division of the trachea

Right

bronchus is wider, shorter, and straighter than leftMore common site for inhaled objects to get stuckSubdivide into smaller and smaller branchesSlide19

Main Bronchi

Figure 13.1Slide20

Lungs

Occupy most of the thoracic cavity

Heart occupies central portion called

mediastinumApex (superior part) is near the clavicle

Base

(inferior part) rests

on the

diaphragm

Each lung is divided into lobes by fissures

Left

lung has two

lobes

Right

lung has three

lobesSlide21

Lungs

Figure 13.4aSlide22

Covering of lungs:

Serosa

covers the outer surface of the lungsPulmonary (visceral) pleura covers the lung surfaceParietal pleura lines the walls of the thoracic cavityPleural fluid fills the area between layers of pleura to allow gliding = less frictionSlide23

Bronchial (Respiratory) Tree Divisions

All but the smallest of these passageways have reinforcing cartilage in their

walls

Largest to smallest:Primary bronchiSecondary bronchi

Tertiary bronchi

Bronchioles

Terminal bronchiolesSlide24
Slide25

Respiratory Zone

Structures from largest to smallest:

Respiratory bronchioles

Alveolar ductsAlveolar sacs

Alveoli (air sacs

) – 40x more surface area than skin

Site of gas exchange = alveoli onlySlide26

Respiratory Membrane (

Air-Blood Barrier)

Walls of alveoli are thin

squamous epithelial layer (much thinner than tissue paper!)

Alveolar pores connect neighboring air

sacs incase mucus blocks other paths

Pulmonary capillaries cover external surfaces of

alveoli

O

ne

side of

membrane

is air and

the

other side is blood flowing

past

Also has:

Alveolar macrophages (“dust cells”) that remove bacteria and

debri

Cuboidal

cells that make surfactant (prevent alveoli from collapsing)Slide27

Respiratory Membrane (Air-Blood Barrier)

Figure 13.6 (1 of 2)Slide28

Respiratory Membrane (Air-Blood Barrier)

Figure 13.6 (2 of 2)