Human Anatomy Unit 7 - Respiratory System

Nose

Nose

Filters and moistens air

Pharynx

• Directs air to respiratory tract

• Eustachian tubes connect from pharynx to ear to stabilize pressure

Larynx

• “Voicebox”

• Contains vocal cords

• Epiglottis covers larynx when swallowing

Epiglottis

• Made of elastic cartilage

• Allows air to enter lungs

• Prevents food/liquid from entering the lungs while eating

Trachea

• Cleans, warms, and moistens incoming air

  • Stiff cartilage rings surrounds trachea to keep it open

  • Last cartilage ring is sensitive

    • Triggers cough reflex if anything but air enters

Bronchi

• Right & left branches

• Connects trachea with lungs

• Branch into bronchioles

Lungs

• Bronchioles end in alveoli

Alveoli

• Site of gas exchange

Pleural Fluid

• Enables lungs to move easily during respiration

  • Natural lubricant

Pleural Effusion

• Excess amount of fluid in pleural cavity

• Limits ability for lungs to expand during inhalation

• Can be seen in symptoms if you have…

  • Heart failure

  • Pneumonia

  • Lung Cancer

Pleural Effusion Treatment

• Thoracentesis

  • Process to remove excess fluid

Surfactant

• Produced by alveoli

• Made of lipids and proteins

  • Breaks apart cohesiveness of water —> surface tension decreases

    • Less energy is required to expand lungs

Respiratory System Image

Breathing is controlled by the…

• Respiratory center in the medulla oblongata

  • Located in brain stem

Inhalation/Exhalation Image

Inhalation: Step 1

• Nerve impulses

• Diaphragm contracts and moves farther down in the abdominal cavity

Inhalation: Step 2

• Increased size of chest cavity —> decreases pressure within lungs

• Air moves from HIGH to LOW pressure —> air flows into lungs

Inhalation: Step 3

• External intercostal muscles raise ribs and expand thoracic cavity

Exhalation: Step 1

• NO nerve impulse

• Diaphragm relaxes and moves farther up in the abdominal cavity

Exhalation: Step 2

• Decreased size of chest cavity —> increases pressure within lungs

• Air rushes out of lungs

Exhalation: Step 3

• Internal intercostal muscles decrease thoracic cavity and lower ribs

“Mouth Breathers”

• Urinate more at night, become more dehydrated

• Sinuses produce x6 the amount of nitrous oxide

  • Nitrous oxide: simulates pituitary gland, tells kidney to store water, prevents urination during the night

Cystic Fibrosis

• Recessive, autosomal genetic disorder

• Build up of thick mucus in the lungs

  • Makes breathing difficult

  • Frequent infections

    • Build up in pancreas and digestive system

• Average life expectancy - 37.41 years

CF Causes

• Mutation in CFTR gene

  • Changes how salt moves in & out of cells lining the lungs & other organs

• Results in thick, sticky mucus building up in respiratory, digestive, & reproductive tracts

CF Image

CF Treatments

1. Medication: CFTR Modulator

2. Gene Therapy

3. Using GE Stem Cells

CFTR Modulator

• Targets the CFTR protein that is caused by a mutation in the CFTR gene

• Does not correct the mutation in the gene

  • Targets the errors that occur after transcription

    • (Making the protein & forming the protein’s the proper shape)

Gene Therapy

• Goal

  • To deliver correct CFTR gene to patients with CF

• Challenges

  • Delivery is difficult because vectors that normally deliver the “working copy” are blocked by thick mucus

  • Respiratory tract cells divide/replace quickly so the application of the new gene needs to be repeated

Using GE Stem Cells

• 2½ hours of aerosols each morning + 1½ hours each night

  • To maintain lung function and prevent infection

• Proven to be safe

CF Current Research

• Infusing genetically modified stem cells (CFTR gene mutation corrected)

  • Stem cells can replace the affected cells with healthy ones

  • GE stem cells carry new genetic codes —> correcting the mutation of thick mucus

  • Hopes to reduce inflammation, improve length & quality of life for CF patients

Small cell lung cancer

• Less common (15%)

• Spreads more quickly and aggressively

Non-small cell lung cancer

• More common (85%)

• Spreads slower, not as aggressive

Tuberculosis

• Caused by a bacterium called Mycobacterium tuberculosis

Asthma

• A disease that affects your lungs with wheezing and breathlessness

Pneumonia

• Inflammation and fluid in your lungs caused by a bacterial, viral, or fungal infection

Emphysema

• A condition in which the air sacs of the lungs are damaged and enlarged

Bronchitus

• Inflammation of the tubes that carry air to and from the lungs

Asbestosis

• A chronic lung disease caused by inhaling asbestos fibers

Sinusitis

• An inflammation of the tissues in your sinuses

Pulmonary Edema

• A condition caused by too much fluid in the lungs

Swine Influenza

• A respiratory disease of pigs caused by type A influenza viruses