Breathing and the Respiratory System

Breathing Ventilation Gaseous Exchange Inhalation Exhalation Respiration

Ventilation- Inhalation and Exhalation Inhalation is the process by which oxygen is moved into the body. Exhalation is the process by which Carbon Dioxide is released / removed from the body

Inspiration (Inhalation) Ventilation Inspiration (Inhalation) External Intercostals (muscles) contract Internal Intercostals (muscles) relax Rib cage pulled upwards and outwards as diaphragm contracts and flattens downwards Volume of the chest cavity (thorax) increases Lung volume increases Air pressure in the lungs decreases Air rushes in to equalise the pressure

Expiration (Exhalation) External intercostals (muscles)relax Internal Intercostals (muscles)contract Rib cage pulled inwards and downwards as diaphragm relaxes and curves upwards (dome shape) squeezing lungs Volume of the chest cavity (thorax) decreases Air pressure in the lungs increases Air flows out to equalize pressure

The Respiratory System NASAL CAVITY warms, moistens & filters inhaled air PHARYNX - passageway for air into the trachea LARYNX- with vocal chords TRACHEA- tube kept open by rings of cartilage and lined with fine hairs or cilia which filter air BRONCHIOLES- smaller branches leading to alveoli BRONCHI- branches leading to each lung LUNG-made up of air sacs or alveoli where gases (oxygen & carbon dioxide) are exchanged PLEURAL MEMBRANE with pleural fluid to keep lung moist RIB CAGE- protects lung DIAPHRAGM- thin sheet of muscle

Gaseous Exchange Internal Gaseous exchange between alveoli in the lungs and the red blood cells in the capillaries that surround it. External gaseous exchange occurs between the red blood cells and the body’s organs.

Gaseous Exchange in Humans Oxygen from the air dissolves in the fluid lining the surfaces of the air sacs A diffusion gradient is established between the oxygen in the air and that in the blood Oxygen in solution moves along this gradient from the alveoli to the blood At the same time carbon dioxide diffuses in the opposite direction

Gaseous Exchange Oxygen from air dissolves in fluid around alveoli There is more oxygen in air than in blood Oxygen in solution diffuses across the alveoli into blood Carbon dioxide diffuses in the opposite direction Oxygen diffuses into the red blood cell Carbon dioxide diffuses into the alveoli In Tissue Carbon dioxide diffuses into blood and Oxygen diffuses into the cells

Activity one You were given a label and you represent a part of the Respiratory system. Verbally and Physically demonstrate the movement of Oxygen across the alveoli and Carbon dioxide from the blood. Be sure to mention differences in concentration of the two gases and how it affects their movement across the alveoli.

Common factors to all respiratory systems Property of Respiratory Surface Function 1. THIN DIAMETER To allow for easy diffusion of gases across the respiratory surface membrane 2. Close proximity to transport system In order to remove gases to and from the blood cells efficiently 3. Moist To prevent the cells on the respiratory surface from drying out and dying and to allow for faster diffusion of the gases across the membrane. 4. Large surface Area To allow a lot of Oxygen to be able to diffuse simultaneously thus increasing the efficiency of the process. 5. Good Supply of Oxygen Because Oxygen is necessary for gaseous exchange and subsequently respiration to take place

Activity 2 Take a look at the fish gill in front of you! Make an annotated drawing of the gill and answer the following questions What is the function of the gill? What are the functions of each part of the gill? Suggest why a fish is unable to breathe out of water

Air Air is a mixture of gases in the following proportions: Inhaled Air Exhaled Air Oxygen - 21% Carbon dioxide - 0.04% Nitrogen – 79% Water vapour - varies Oxygen -16% Carbon dioxide – 4% Nitrogen – 79% Water vapour - varies

Respiration (all living things) At the cell Gaseous exchange takes place Oxygen enters the cell and moves to the mitochondria where respiration takes place. Respiration (all living things) Glucose + Oxygen Carbon dioxide + Water + Energy Carbon dioxide made in the cell diffuses back into the blood Energy is used by cells Oxygen Carbon dioxide

RESPIRATION Yeast Anaerobic Aerobic Muscle Glucose + Oxygen Carbon dioxide + Water + Energy Glucose Carbon dioxide + Ethanol + Energy Glucose Lactic acid+ Energy ( in mitochondria of cells) (in all living things when Oxygen is present) (in muscle and yeast when Oxygen is absent)

Which part of the respiratory system moistens the air entering the body? The diaphragm gets flat when you _____. The ribcage moves downwards and inwards when you __________. Name one process involved in breathing. Another name for air sacs is _____. Another name for the larynx is the ____________. During gas exchange which gas enters leaves the tissues and enters the red blood cells? What is the function of the rings of cartilage around the bronchus? Another name for the wind pipe is the ________. The lungs are protected by what part of the respiratory system? Ventilation is made up of two processes. During inhalation the volume of the chest cavity ___________. During inhalation the air pressure inside the lungs ___________. When we breathe out how is the diaphragm shaped? What keeps the lungs moist?