The Respiratory System Mr. Lane

Review of Cellular Respiration: Requirements: Glucose O2 The O2 needed for Cellular Respiration is obtained by the respiratory system through the process of breathing.

The Respiratory System

Function of the Human Respiratory System: A network of passages that allow gases to pass from the external environment to the internal surfaces of the lungs.

The pathway of air…

The Nasal Cavity Exposed to air through nostrils. Lined with cilia (small hairs) and mucous membranes which______, _______, and ______ air. Filter Warm Moisten

The Pharynx & Larynx The oral and nasal cavity meet at the pharynx, which is more commonly referred to as the throat. The pharynx contains the Larynx, where the voice box and vocal cords are located.

The Trachea Also referred to as the “windpipe.” Held open by rings of cartilage. Cilia and mucus line the trachea in order to trap microscopic particles. Food is prevented from entering the trachea by the epiglottis.

The Bronchi & Bronchioles 2 main branches of the trachea. Lined with mucus and ringed with cartilage. The Bronchioles Many subdivisions Lined with mucus NO CARTILAGE.

The Alveoli Site of gas exchange between the lungs and the blood. O2 out of the alveoli CO2 into the alveoli QUESTION: What type of blood vessel is holding the blood being exchanged? The walls of the alveoli and capillaries are so thin that the gases can easily diffuse out of one and directly into the other.

Think of it like a tree! Tree Trunk: Trachea Large Branches: Bronchi Smaller Branches: Bronchioles Leaves: Alveoli

The Path of Air Nasal Cavity– air is filtered, warmed, and moistened. Pharynx – intersection of paths for food and air. Larynx (Voice Box) Trachea (Windpipe) – food blocked by epiglottis Bronchi (2) Bronchioles (many) Alveoli (millions) – site of gas exchange

Regulation of Breathing Breathing Rates are controlled by the Medulla in the brain. When a large amount of CO2 is detected, the Medulla sends a signal to the diaphragm to contract. The contraction of the diaphragm causes the lungs to expand and breathing to occur.

The Diaphragm Dome-shaped sheet of muscle located directly below the lungs. Inhalation: Lungs/Chest expand Diaphragm contracts Exhalation: Lungs/Chest contract Diaphragm relaxes

Malfunctions of the Respiratory System Bronchitis Asthma Emphysema occur.

Bronchitis The mucus membrane in the bronchial passages becomes inflamed. Narrows/shuts down airway Cause: Lung infections caused by viruses, pollution, smoking, etc. Treatment: Rest, fluids, avoiding smoke and fumes.

Asthma Chronic lung disease that enflames and narrows the airways. Results in wheezing, chest tightness, shortness of breath, and coughing. Cause: genetic, increased risk of allergies, environmental exposure. Treatment: avoiding trigger, inhaled corticosteroids.

Emphysema Alveoli are severely damaged and air pockets develop resulting in airflow limitation (trouble breathing in and out). Cause: Cigarette smoking / second hand smoke. Treatment: No cure; medications or direct oxygen supply can limit the effects.