Respiratory TractGas Exchange

BreathingDisease

Respiratory System

Respiratory Tract

Nasal (or oral) cavity

PharynxLarynxTracheaBronchiBronchioleAlveoli

Nasal Cavity

3 main functions: Cleans the air –

nostrils contain tiny hairs that trap dirt particles

Warms the air – capillaries carrying warm blood

Moistens the air – membranes that secretes mucus

Pharynx (throat)

The place where the nasal cavity, esophagus (digestive tract) and trachea (respiratory tract) meet

Epiglottis is the door that allows food down to go down the esophagus (digestive tract) and air down the trachea (respiratory tract)

https://www.cdli.ca/courses/biol2201/unit03_org03_ilo02/8_12_cap.jpg

Larynx (voice box)

Houses the vocal cords Vibrations of the cords produces sound

Larynx (voice box)

http://www.sciencephoto.com/image/309652/530wm/P4960012-Resting_larynx-SPL.jpg

Trachea (windpipe)

Composed of cartilage (soft bone)

Helps maintains rigidity to prevent the respiratory passage from collapsing

Trachea (windpipe)

Lined with ciliated epithelial cells

Cells secrete mucus which traps foreign particles

Cilia brush the mucus up the respiratory tract

We sneeze or cough to expel mucus that has trapped foreign particles

Bronchi

The trachea branches into 2 bronchi leading to the left and right lung

Bronchi branch into smaller bronchiole eventually ending at the alveoli

Structures are reinforced with cartilage

Alveoli

Spherical hollow cavities increase surface area

Walls are only 1 cell thick making it easy for rapid diffusion

Capillaries line the alveoli for gas exchange

Gas Exchange

Alveoli:Gas Exchange

Oxygen goes into the blood vessel.

Carbon dioxide (a waste product) leaves the blood vessel into the alveolus.

Breathing

Process Inhalation: taking air into the lungsExhalation: breathing out air

MusclesDiaphragm (between lung and

stomach)Ribcage muscles

Breathing

Breathing

ProcessRib

MusclesRib

CageDiaphrag

mVolume

Internal Pressur

eAir

Inhalation

Contract

Expand

(up and out)

Contract(moves down)

Flattens

IncreaseDecreas

eMoves

in

Exhalation

Relax

Reduce

(down and in)

Relax(moves

up)Dome-shaped

Decrease

IncreaseMoves

out

Breathing

InvoluntaryCan override system temporarily

(e.g. hold our breath)Breathing rate determined by

amount of carbon dioxide detected in blood

When carbon dioxide increases, breathing rate increases, heart beats faster to let in more oxygen

Respiratory Diseases

LaryngitisBronchitisAsthmaPneumoniaEmphysemaTurberculosis (TB)SARS

Laryngitis

Inflammation of the vocal cords.

Caused by overuse, irritation, infection

Laryngitis Left: inflamed larynx (v-shaped flaps) Right: thickening of vocal cords in response to

chronic irritation (white, centre) Swollen vocal cords lose ability to vibrate. Voice becomes husky or is lost completely. Treatment: rest, remain in warm moist

environment

http://www.sciencephoto.com/media/259305/enlarge http://www.sciencephoto.com/media/259306/enlarge

Bronchitis

Inflammation of bronchi.

Caused by: Microorganisms

: virus, bacteria Environment:

pollution, dust, smoke

Irritation causes bronchi to swell.

Bronchitis

Cilia immobilized

Respiratory passage clog with debris

Heavy mucus formed resulting in a cough

http://nursingcrib.com/wp-content/uploads/acutebronchitis1.jpg?9d7bd4

Asthma

Chronic, inflammatory disease resulting in obstructed airflow.

Inflammation and swelling of bronchiole walls produces extra mucus

Constriction of muscles around bronchiole

Asthma

http://www.h2oclinic.ca/image/image_gallery?uuid=493f1463-6906-44b4-b518-8a4c0ad01456&groupId=11922&t=1318259516955

Asthma Allergies and air

pollution can trigger asthma.

Condition is usually reversible

Short term treatment: puffers that contain bronchiodilators

Long term treatment: anti-inflammatory drugs, anti-allergy shots

Pneumonia

Infection of the lungs, leading to fluid in the alveoli.

Caused by a microorganism

Treated with antibiotics

Smoking

Injures the cilia of the trachea so that they cannot remove foreign particles as effectively.

Tar, a black sticky sooty material, a by-product of burning tobacco, coats the lungs.

Key cause of lung cancer.

Emphysema

Alveoli become brittle

Alveoli walls fuse together

Reduces the surface area for gas exchange

Lung loses elasticity

Emphysema

http://4.bp.blogspot.com/-6KVgA73rT1s/TWUCABgY_DI/AAAAAAAAAMs/DsPuXUxrMRI/s1600/smokinglungs.jpg

Emphysema

http://www.diagnosisaday.com/wp-content/uploads/2010/12/COPD.jpg

Tuberculosis (TB) Infectious disease caused by a

bacteria that grows in the lung

Conceptual image of Mycobacterium Tuberculosis bacteria on a cellular surfacehttp://www.sciencephoto.com/image/143129/530wm/C0080175-Conceptual_image_of_TB_bacteria-SPL.jpg

Tuberculosis (TB)

Symptoms are general: fever, cough, chest pain, tiredness

Bacteria can remain dormant in body for decades and can also recur in patients who have had TB before

Diagnosis: chest x-ray, swab

.Coloured X-ray (front view) of the chest in a 50 year old male patient, showing fibrosis in the lungs from old tuberculosis (orange, at upper left) and an infection of new tuberculosis (green, at right). TB can recur at periods when the patient's immune system is weakened.

Tuberculosis (TB)

Chest x-ray of a 25 year old male patient with TB.

Lung (dark areas) show grainy white patches which are the affected areas.

http://www.sciencephoto.com/image/415340/530wm/C0103593-Tuberculosis,_X-ray-SPL.jpg

Tuberculosis (TB)

Chest x-ray (left: traditional, right: coloured) in a 14 year old male patient with TB Inflamed lymph nodes (left: centre right, right: blue) Fluid collected between the lung lobes (left: pale line at left, right: yellow)

SARS

Severe acute respiratory syndrome

Epidemic gripped Toronto in 2003

Spread from a region in China

44 deaths in Canada of 438 cases

SARS Outbreak

http://tnpgallery.files.wordpress.com/2008/12/sars-outbreak.jpg

SARS

Symptoms: flu like, high fever, shortness of breath, dry cough, sore throat, headache, muscle pain, exhaustion

Diagnosis: chest x-ray, swab

SARS Fashion makes

things less frightening. It is able to take the focus away from the potentially lethal infectious airborne disease.

These folks are all in Hong Kong where they were protecting themselves against the SARS epidemic.

http://cellar.org/2003/maskfashion.jpg