The Respiratory System Just Breathe!

Interesting Facts The right lung is slightly larger than the left. We lose half a litre of water per day breathing. At rest, the average adult takes in and breathes out 6 litres of air each minute.

Breathing Experiments: Page 287 - Hold your breath Page 287 - Breaths per minute The average adult takes 12 breaths/min In an average lifetime (74 years), does a person take more breaths or heartbeats? Heartbeats! 3 billion to 600 million breaths! Hold nose and breathe Bend forward and breathe Hold your ribs!

The Respiratory System: Respiration: all processes involved in the exchange of oxygen and carbon dioxide between cells & the environment O2 CO2

The Respiratory System: For Animal, Respiration Has 2 Purposes: To get oxygen (O2) to its cells To get rid of excess carbon dioxide (CO2) O2 CO2

Types of Respiration: (P.289) External Respiration In our Lungs! gas exchange between blood and the surrounding air (Diffusion)

Types of Respiration: Internal Respiration In our cells! gas exchange between blood and cells (by diffusion also) Provides O2 for Cellular Respiration

Circulation of Oxygen Red Blood cells are O2 “Taxis” They contain Hemoglobin! When blood has a low O2 [ ](deoxygenated) the hemoglobin is dark red/purple! When blood has high O2 [ ](oxygenated) the hemoglobin is bright red!

The LUNGS Massive amount of surface area…increased gas exchange efficiency! Ave. surface area = 70m2 Spread out flat, the lungs would provide enough space for seven cars! The word ‘lung’ comes from the Greek word meaning ‘light’. Lungs are the only human organs light enough to float! The average male will breathe out enough air over his lifetime to fill 250 two-person hot air balloons! That’s a lot of hot air… Ba dum bump!

You’ve got… 2:00 Structures: Label Them! GO!!!

1:45 Structures:

1:30 Structures:

1:15 Structures:

1:00 Structures:

0:45 Structures:

0:30 Structures:

0:15 Structures:

Time’s Up!!! 0:00 Structures: Nose Mouth Larynx Lung Rt. Bronchus Diaphragm Pharynx Trachea Lt. Bronchus Bronchiole Alveoli

External Respiration: Fxns! Nasal Passage: Air is warmed, humidified and filtered & cleaned by cilia and mucous lining. Oral Cavity: Passage of air Pharynx: Common pathway for air and food. Larynx: Adam’s apple. Produces sound (vocal cords) Trachea: Epiglottis opens allowing air to move down the cilia and mucous-lined trachea to one of two bronchi, heading to the lungs.

External Respiration: Fxns! Bronchi: Main branches of the trachea Divide to form bronchioles, and air eventually reaches tiny air sacs called alveoli. Gas exchange occurs at the alveoli – O2 moving into the blood, and CO2 moving out. Oxygen is distributed to the cells of the body via the blood (pumped by the heart!) Ribs: protect the lungs and heart, aid in breathing. Lungs: major organ of respiration (duh!)

Gas Exchange @ the Alveoli Each alveolus is only one cell thick and is very moist. This facilitates diffusion! 240 alveolar membranes stacked together would only be as thick as a sheet of paper! Each lung contains 150 million alveoli!

Alveoli: Air Sacs!

External Respiration: 2 Phases: Inspiration diaphragm contracts and moves downward (flattens), volume increases, creating low pressure and drawing air in Expiration diaphragm relaxes, volume decreases, creating high pressure, forcing air out

The Diaphragm! Complete Diaphragm Worksheet!!

Breathing Physiology Quickly complete worksheet (use P. 297) Tidal Volume: Demo Vital Capacity: Quick Experiment! Vital Capacity can be… - Increased by training (i.e. swimmers ~6L) - Decreased by smoking!

Feedback Regulation The Medulla Oblongata is the control centre in the brain! CO2 levels in the blood increase, making the blood acidic. Chemoreceptors in the aorta and other large arteries sense this change and relay a message to the brain. Brain sends a message to the diaphragm and intercostal muscles of ribs to increase breathing rate. Homeostasis is restored!

Diseases & Health Problems: Obstructive Diseases (e.g., Emphysema, Bronchitis, Asthma) Restrictive Diseases (e.g., Cystic Fibrosis, Alveolar Damage) Vascular Diseases (e.g., Pulmonary Edema) Infectious Diseases: (e.g., Pneumonia, Influenza, Tuberculosis) Environmental Irritants: (e.g., Asbestos, Particulate Pollutants, SMOKING!) F.Y.I. Coughing is of major importance, as it is the bodies main method to remove dust, mucus, saliva, and other debris from the lungs. Inability to cough can lead to infection.

Treatment Options Asthma – Caused by contracting muscles that surround bronchi. Air mov’t is restricted. Puffers contain “bronchodilators” that relax the muscles.

Treatment Options Bronchitis & Emphysema- Mucous layers are broken down, dirt/particles collect in lungs and damage alveoli. Caused by smoking and other environmental irritants (‘Darts’ contain ~4000 chemicals!). Must use a portable O2 delivery system to compensate for less gas exchange surface.

Any one for a smoke?

Altitude Sickness High Altitude Pulmonary Edema (fluid in the lungs) - persistent dry cough, fever and shortness of breath even when resting HAPE can lead to… High Altitude Cerebral Edema (swelling of the brain) - headache that does not respond to analgesics, unsteady walking, increasing vomiting and gradual loss of consciousness Mount Everest – 8 848 m (29 028 ft)

Mount Everest May 12, 2006: Ed Viesturs became the first American to summit all 14 8000m peaks without the use of supplemental oxygen!! "I am nothing more than a single narrow gasping lung, floating over the mists and summits." Reinhold Messner Above 8000m is called the “Death Zone” As of 2004, 2,238 people had reached the summit (1,148 of them since 1998) and 186 people have died trying!

HAPE- Treatment Acclimatize: “Climb high, Sleep Low” Get to lower altitudes quickly!