The Respiratory System

To Review… Cellular Respiration is… A set of chemical reactions that release energy from food molecules A set of chemical reactions that release energy from food molecules aerobic – uses oxygen & releases 36 ATPs aerobic – uses oxygen & releases 36 ATPs anaerobic – does not use oxygen & releases anaerobic – does not use oxygen & releases only 2 ATPs (per molecule of glucose) only 2 ATPs (per molecule of glucose)

The Human Respiratory System… FUNCTION: a network of passages that allow gases to pass from the external environment to the internal surfaces of the lungs FUNCTION: a network of passages that allow gases to pass from the external environment to the internal surfaces of the lungs

Organization of the Respiratory System Nostrils #1 Nostrils #1 Nasal Cavity #2 Nasal Cavity #2 Pharynx (throat) #3 Pharynx (throat) #3 Epiglottis #4 Epiglottis #4 Larynx (voicebox) #5 Larynx (voicebox) #5 Esophagus #6 Esophagus #6 Trachea (windpipe) #7 Trachea (windpipe) #7 Lung #8 Lung #8 Bronchi #10 Bronchi #10 Bronchioles #11 Bronchioles #11 Diaphragm #12 Diaphragm #12 Alveoli #13 Alveoli #13 Alveolus (air sac) #14 Alveolus (air sac) #14

Nasal Cavity - exposed to air through nostrils - lined with cilia (minute hairs) & mucous membranes which filter, warm & moisten air

Nasal Cavity

Pharynx (throat) Where the oral and nasal cavity meet Where the oral and nasal cavity meet Contains the LARYNX –vocal cords Contains the LARYNX –vocal cords (laryngitis is when you lose your voice) (sometimes it protrudes as the Adams apple) Larynx Video

Trachea (windpipe) Kept open by rings of cartilage Cilia and mucus line the trachea & trap microscopic particles Cigarette smoke & other pollutants interfere with the cilia Food is prevented from entering by the epiglottis

A laryngectomy may result from laryngeal cancer, so… DON’T SMOKE!

Bronchi 2 main branches of the trachea 2 main branches of the trachea Lined with mucus and ringed with cartilage Lined with mucus and ringed with cartilage

Bronchioles Many subdivisions (branches) of the bronchi Many subdivisions (branches) of the bronchi Lined with mucus Lined with mucus NO rings of cartilage NO rings of cartilage (during asthma these close up causing wheezing)

Alveoli (air sacs) respiratory surface where O 2 and CO 2 are exchanged through diffusion respiratory surface where O 2 and CO 2 are exchanged through diffusion at the ends of the bronchioles at the ends of the bronchioles Thin and moist Thin and moist Surrounded by capillaries Surrounded by capillaries Oxygen enters the capillaries from the alveoli Oxygen enters the capillaries from the alveoli CO 2 leaves the capillaries and enters the alveoli to be exhaled CO 2 leaves the capillaries and enters the alveoli to be exhaled

Video Gas Exchange CO2 Transport

Lungs Spongy tissue including bronchioles and all alveoli! Spongy tissue including bronchioles and all alveoli!

Diaphragm Diaphragm Muscle that separates the thorax and the abdomen Muscle that separates the thorax and the abdomen Contracts and flattens when you inhale Contracts and flattens when you inhale Relaxes and curves up when you exhale Relaxes and curves up when you exhale Breathing Video Breathing Video Breathing Video Breathing Video Why Do We Yawn? - YouTube Why Do We Yawn? - YouTube Why Do We Yawn? - YouTube Why Do We Yawn? - YouTube

Rib Cage Muscles & Chest cavity Inhaling – rib cage (intercostal) muscles contract and chest cavity enlarges (lowering pressure in the lungs so air rushes in) Inhaling – rib cage (intercostal) muscles contract and chest cavity enlarges (lowering pressure in the lungs so air rushes in) Exhaling – rib cage muscles relax and compressed air is exhaled Exhaling – rib cage muscles relax and compressed air is exhaled

What controls your breathing rate? breathing rate is regulated by the concentration of CO2 and its effect on the medulla (part of the brain) increased CO2 medulla causes increase in breathing rate

What are hiccups??

Malfunctions of the Respiratory System…

1. Pneumonia eeeeffect: Fluid develops in the alveoli ccccause: bacteria or viral infection which persists when immune system is compromised ssssymptoms: fever, chills, fatigue & excessive cough with mucus ttttreatments: antibiotics &rest, wash hands often Video

2. Bronchitis  effect: Inflammation of the bronchial tubes  cause: cigarette smoke, air pollution, dust, toxic gases, viruses  symptoms: cough, mild  fever, tiredness, wheezing  treatments: avoid  irritants, drink liquids, rest rest

3. Asthma eeeeffect: muscular walls of the bronchioles contract and constrict, excess mucus is produced ccccause: triggered by an allergic response or excess smoke, dust, or stress ssssymptoms: Difficulty breathing, chronic cough ttttreatments: Inhaler or nebulizer, anti- inflammatory drugs VIDEO

4. Emphysema effect: the breakdown of alveoli walls and loss of elasticity of lungs cause: 80% of cases due to smoking, air pollution symptoms: chronic cough, shortness of breath treatments: no cure! oxygen therapy, stop smoking to slow progression VIDEO