GASEOUS_EXCHANGE (1)

GASEOUS EXCHANGE: 

GASEOUS EXCHANGE Cellular respiraion is used by all cells to convert the energy in glucose in to the usable form of ATP. The word equation is: Glucose +oxygen= carbon dioxide+ATP. The chemical equation is: C 6 H12O 6 +O2= ATP+CO2+H2O These two gases: oxygen and carbon dioxide must continually be exchanged in the body. The ventilation system makes this exchange possible.

Anatomy of the respiratory system: 

Anatomy of the respiratory system External intercostal muscles

Ventilation system: 

Ventilation system Air is brought into the body by a process called inspiration. This happens when the diaphragm muscle contracts and moves down and the external intercostal muscles contract and move the ribcage out. The action of these 2 muscles causes the volume of the lungs to increase which causes the pressure to decrease . When the pressure in the lungs gets below air pressure then air is sucked in.

Ventilation system: 

Ventilation system Expiration When the pressure inside the lungs is equal to the outside pressure then no more air goes in. The diaphragm and external intercostal muscles then relax and this makes the volume decrease and the pressure increase and so air moves out. Expiration is a passive process. animation

Gaseous Exchange: 

Gaseous Exchange Gases are exchanged between the surface of the alveoli and the capillaries that surround them.

Gaseous Exchange: 

Gaseous Exchange The concentration of oxygen is high in the alveoli compared to the blood, and the concentration of carbon dioxide is low in the alveoli compared to the blood. So how will the gases move and by what process?

Structure/function: 

Structure/function The structure of the alveoli facilitates its function. Alveolar wall is only one cell thick and is moist Alveoli are surrounded by many capillaries and they are in contact with the membrane There are many alveoli paked into the lungs which increases the surface area

Gaseous Exchange: 

Gaseous Exchange The blood leaving the lungs is now high in oxygen and low in carbon dioxide. When the blood gets to the tissues the gases are exchanged again. Oxygen moves down its concentration gradient from the blood to the tissues. Carbon dioxide moves down its concentration gradient from tissue to blood. Why is the tissue low in oxygen and high in carbon dioxide? animation

Percentage of gases in inhaled and exhaled air: 

Percentage of gases in inhaled and exhaled air gas % in inspired air %in expired air oxygen 21 18 Carbon dioxide 0.04 3 Nitrogen 78 78 Explain why these are different

How is breathing controlled?: 

How is breathing controlled? Chemoreceptors in the brain can measure concentrations of and carbon dioxide. This is measured by the amount of H+ ions in the blood (carbon dioxide and water produce a weak acid called carbonic acid) The pH of blood must be maintained within very narrow limits. A normal blood pH is 7.4 but if it gets lower than 6.8 or higher than 7.8 death can occur. Why would excercise cause a drop in pH?

Breath Holding Acivity: 

Breath Holding Acivity

Measuring Respiration and respiratory function: 

Measuring Respiration and respiratory function Respiratory rate is the number of times you inhale per minute. Normal RR is about 12/min. Tidal volume is the amount of air transferred in and out in one normal breath Vital capacity is the MAXIMUM amount of air that can be transferred in one breath. Inspiratory and expiratory reserve : additional air that can be moved in a breath with maximum effort. How would exercise affect these measurements?

Measuring lung function with a Spirometer: 

Measuring lung function with a Spirometer This apparatus measures teh volume of air that is moved with each inspirartion and expiration. It has a drum that moves at a steady rate so you can also measure the rate of breathing. We have the ability to change both the rate and depth of our breathing, which has an effect on teh volume that can be moved with each breath. Even taking the deepest exhalation possible there ill be some air left in the lungs, which is called the residual volume.

Spirometer tracing: 

Spirometer tracing

Smoking and Health: 

Smoking and Health Pay to Die

Toxic chemicals in cigarettes:: 

Toxic chemicals in cigarettes : Carbon monoxide: binds with oxygen, kills cilia Benzene: causes leukemia Arsenic: causes damage to blood vessels Tar: a mixture of lots of chemicals Formaldehyde: causes lung cancer Cyanide: damages heart tissue and vessels Chromium: causes lung cancer Butidiene: very carcinogenic Polycyclic hydrocarbons: also very carcinogenic Polonium 210: radioactive element, causes damage to DNA

Effects on health: 

Effects on health Increases risk of: Coronary heart disease Stroke Chronic Obstructive lung disease and emphesyma Lung Cancer Kidney, bladder, mouth, stomach, esophageal, blood cancers

PowerPoint Presentation: 

7 deadly myths