SACCONE IS THE COOLEST Chapter 18 Human Respiration

SACCONE IS THE COOLEST Human Respiration Involves the process of cellular respiration and gas exchange a) cellular respiration: glucose + O 2  H 2 O + CO ATP’s b) gas exchange: exchange of gases between the internal and external environment with the use of lungs

SACCONE IS THE COOLEST (I) Human Respiratory System Composed of a network of passageways which permits air to flow from the external environment and into the lungs

Human Respiratory System

SACCONE IS THE COOLEST Nasal Cavity The nose Lined with a ciliated mucus membrane The cilia and mucus: 1. Filters air 2. Warms air 3. Moistens air

SACCONE IS THE COOLEST Pharynx Known as the throat region It is an area in which both air and food pass through

SACCONE IS THE COOLEST Larynx Also called the Adam’s apple Humans use the larynx as a voice box which contains vocal cords that vibrate and produce sound as air passes through

SACCONE IS THE COOLEST Epiglottis A cartilaginous flap It “covers” the trachea when swallowing food

SACCONE IS THE COOLEST Trachea Known as the windpipe Kept open by rings of cartilage Lined with a ciliated mucus membrane One cigarette paralyzes the cilia for 20 minutes

SACCONE IS THE COOLEST Bronchi Bronchus = singular Trachea divides into two major divisions known as bronchi The bronchi contain cartilage rings as well The bronchi subdivide many times forming smaller tubules known as bronchioles

SACCONE IS THE COOLEST Bronchioles Lack cartilage rings Tiny bronchioles subdivide and terminate (end) with structures known as alveoli

SACCONE IS THE COOLEST Alveoli Are thin, moist and surrounded by capillaries Are the functional units for gas exchange between the lung and the blood Alveoli increase surface area for gas exchange O2 diffuses into the blood from the alveoli and CO2 and water diffuse out of the blood and into the alveoli

Gas Exchange at the Alveolus

SACCONE IS THE COOLEST Diaphragm Muscle that forms the floor of the chest cavity Aids in the breathing process

SACCONE IS THE COOLEST (II) Breathing Process Lungs are highly elastic (stretchable) Breathing is controlled by the medulla Movement of the diaphragm and ribcage causes pressure change in the chest cavity which moves air into and out of the lungs The breathing rate is controlled by the concentration of CO2 in the blood Inhalation- breathe in Exhalation- breathe out

SACCONE IS THE COOLEST (IV) Gas Exchange 1. In the blood, hemoglobin binds with oxygen from the alveoli to form oxyhemoglobin (HbO 2 ) 2. Carbon dioxide is carried primarily in the plasma of the blood in the form of bicarbonate ions (HCO 3 )

SACCONE IS THE COOLEST Diseases of the Respiratory System

SACCONE IS THE COOLEST Bronchitis Inflammation of the membrane of the bronchial tubes

SACCONE IS THE COOLEST Asthma An allergic response characterized by constriction of the bronchial tubes

SACCONE IS THE COOLEST Emphysema Disease in which the walls of the alveoli breakdown, decreasing surface area for gas exchange Characterized by shortness of breath, difficulty in breathing, and decreased lung capacity

SACCONE IS THE COOLEST Pneumonia The alveoli become filled with fluid, preventing gas exchange between the alveoli and the capillaries