GAS EXCHANGE
GAS EXCHANGE
 HOW DO WE REMEMBER ALL THE LIFE PROCESSES?
 H.N.T.R.S.G.E.R.M.R
 WHICH ONES HAVE WE DISCUSSED IN GREATER DETAIL TO
THIS POINT?
 NUTRITION & TRANSPORT
 WHAT’S NEXT ON THE LIST?
 R = RESPIRATION
 WHAT IS RESPIRATION?
 TWO TYPES
 CELLULAR RESPIRATION VS GAS EXCHANGE
GAS EXCHANGE
 CELLULAR RESPIRATION REMINDER
GAS EXCHANGE
 CELLULAR RESPIRATION REMINDER
 WHAT SUBSTANCE MUST BE PRESENT TO GO FROM
GLYCOLYSIS TO THE REACTIONS INSIDE THE
MITOCHONDRIA??
OXYGEN!!!
GAS EXCHANGE
 NOW, LET’S TALK GAS EXCHANGE…
 GAS EXCHANGE
 DEF  THE PHYSICAL METHODS ORGANISMS HAVE FOR
OBTAINING OXYGEN FROM THEIR SURROUNDINGS, AND
REMOVING EXCESS CARBON DIOXIDE FROM THEIR INSIDES
 BECAUSE OF THIS OVERLAP WITH OXYGEN AND CARBON
DIOXIDE, THE TERM RESPIRATION IS INCLUSIVE OF BOTH
CELLULAR RESPIRATION AND GAS EXCHANGE, BUT THESE
ARE TWO DIFFERENT PROCESSES!!
GAS EXCHANGE
 BECAUSE OF THE SMALL SIZE OF GASES, THEY CAN
EASILY DIFFUSE THROUGH MEMBRANES; HOWEVER, THIS
IS DEPENDENT ON TWO FACTORS
 MOIST MEMBRANES (RESPIRATORY SURFACES)
 DIRECT CONTACT WITH THE ENVIRONMENT
GAS EXCHANGE
 RESPIRATORY SURFACES
 THE SURFACE (BOUNDARY) THROUGH WHICH GAS
EXCHANGE TAKES PLACE
GAS EXCHANGE
 RESPIRATORY SURFACE
 MUST BE THIN-WALLED SO DIFFUSION ACROSS IT CAN
OCCUR RAPIDLY
 IT MUST BE MOIST BECAUSE THE OXYGEN AND CARBON
DIOXIDE MUST BE IN SOLUTION
 IT MUST BE IN CONTACT WITH A SOURCE OF OXYGEN THAT
EXISTS IN THE SURROUNDINGS
 IN MOST MULTI-CELLULAR ORGANISMS, IT MUST BE IN
CONTACT WITH THE TRANSPORT SYSTEM THAT CARRIES
DISSOLVED MATERIALS TO AND FROM THE CELLS OF THE
ORGANISM
GAS EXCHANGE
 GAS EXCHANGE IN PROTISTS
 DO THEY NEED A RESPIRATORY SYSTEM?
GAS EXCHANGE
 GAS EXCHANGE IN PROTISTS
 THEY CAN RELY ON SIMPLE DIFFUSION ACROSS THEIR CELL
MEMBRANE.
 WHAT IS THE
RESPIRATORY SURFACE
IN PROTISTS?
 WHY MUST PROTISTS
LIVE CONTINUOUSLY IN
WATER?
GAS EXCHANGE
 GAS EXCHANGE IN HYDRAS
 DO THEY NEED A RESPIRATORY SYSTEM?
 WHY DON’T THEY NEED
A RESPIRATORY SYSTEM?
 HOW DOES THE OXYGEN AND
CARBON DIOXIDE MOVE IN
AND OUT?
 WHAT IS THE RESPIRATORY
SURFACE OF THE HYDRA?
 WHERE MUST HYDRAS
LIVE?
GAS EXCHANGE
 GAS EXCHANGE IN THE EARTHWORM?
 DO EARTHWORMS HAVE RESPIRATORY SYSTEM?
 EVER WONDER WHY EARTHWORMS
ARE SO SLIMY?
 THEY SECRETE A SPECIAL MUCUS TO
CONSTANTLY KEEP THEIR SKIN
MOIST!! (HINT AT SOMETHING??)
 THE SKIN IS THE RESPIRATORY
SURFACE FOR THE EARTHWORM 
 WHY DO EARTHWORMS LIVE IN THE
“EARTH”?
 WHAT HAPPENS WHEN IT RAINS?
WHEN IT STOPS?
GAS EXCHANGE
 GAS EXCHANGE IN THE EARTHWORM
 THE GASES DIFFUSE DIRECTLY
INTO/OUT OF THE BLOOD OF
THE EARTHWORM (TURNING
THE BLOOD RED)
 WHY IS AN EARTHWORM’S
BLOOD RED?
GAS EXCHANGE
 GAS EXCHANGE IN THE GRASSHOPPER
 DO GRASSHOPPERS HAVE RESPIRATORY SYSTEMS?
 CAN THE SKIN BE THE RESPIRATORY
SURFACE?
 INSECT’S EXOSKELETONS ARE MADE OF
CHITIN…ANYONE REMEMBER WHAT
THAT IS?
 HOW DOES THE GAS GET IN?
 SPIRACLES + TRACHEAL TUBES + AIR SACS
GAS EXCHANGE
 GAS EXCHANGE IN THE GRASSHOPPER
 SPIRACLES
 OPENINGS IN THE EXOSKELETON TO
ALLOW GASES IN
 TRACHEAL TUBES
 TUBES FOR THE GAS TO TRAVEL WITHIN
THE BODY
 THEY BRANCH AND TRAVEL THROUGHOUT
THE GRASSHOPPER BODY CARRYING
GAS DIRECTLY TO THE CELLS
 AIR SACS
 BALLOON LIKE STRUCTURES THAT HELP
PUMP THE AIR IN AND OUT OF THE TUBES
GAS EXCHANGE
 HOW COME WE DON’T DO GAS EXCHANGE THROUGH
OUR SKIN LIKE THE EARTHWORM, OR THROUGH
SPIRACLES AND TUBES LIKE THE GRASSHOPPER?
 THE SIMPLE ANSWER IS WE NEED WAY MORE OXYGEN THEN
THESE SYSTEMS CAN PROVIDE…SO WE NEED A MORE
COMPLEX SYSTEM
 BEFORE HUMANS, THOUGH, JUST A QUICK NOTE ABOUT
COMPLEX ANIMALS THAT LIVE IN WATER FULL
TIME…EXAMPLES???
GAS EXCHANGE
 GILLS
 VERY SPECIAL
STRUCTURE
THAT ALLOWS
CERTAIN
ANIMALS
TO ABSORB
OXYGEN
DISSOLVED
IN WATER
 MUST STAY
MOIST!!
 WHAT HAPPENS
WHEN WE
PULL A FISH
OUT OF WATER?
GAS EXCHANGE
 GILLS HAVE TREMENDOUS SURFACE AREA…WHY???
GAS EXCHANGE
 GAS EXCHANGE IN HUMANS
 DO HUMANS HAVE A RESPIRATORY SYSTEM?
 LET’S BREAK IT DOWN TO UNDERSTAND HOW IT WORKS…
GAS EXCHANGE
 GAS EXCHANGE IN HUMANS
 EXCHANGE PATHWAY
 NOSE / NASAL CAVITY
 PHARYNX
 LARYNX
 TRACHEA
 BRONCHI
 BRONCHIOLES
 ALVEOLI
GAS EXCHANGE
 GAS EXHCHANGE IN HUMANS
 NOSE / NASAL CAVITY
 AIR ENTERS HERE
 LINED WITH HAIR AND
MUCUS…WHY??
 PHARYNX
 THROAT
 NASAL AND ORAL
CAVITY MEET HERE
 WHY CAN YOU BREATH
THROUGH YOUR MOUTH
GAS EXCHANGE
 GAS EXCHANGE IN HUMANS
 LARYNX
 VOICE BOX
 AIR RUSHING PASSED
MAKES CORDS VIBRATE
LIKE GUITAR STRINGS,
CREATING SOUND
 WHY DON’T YOU TALK
WITH FOOD IN
YOUR MOUTH??
GAS EXCHANGE
 GAS EXCHANGE IN HUMANS
 TRACHEA
 A.K.A. WIND-PIPE
 CONNECTION TO LUNGS
 BRONCHI
 TRACHEA SPLITS IN TWO
TUBES, ONE FOR EACH
LUNG
 BRONCHIOLES
 BRONCHI SPLIT INTO MANY
TINY BRANCHES
 WHY DO YOU THINK IT IS
IMPORTANT TO HAVE MANY
BRANCHES?
GAS EXCHANGE
 GAS EXCHANGE IN HUMANS
 ALVEOLI
 TINY GRAPE LIKE SACS
WHERE GAS EXCHANGE
ACTUALLY TAKES PLACE
 SURROUNDED BY
CAPILLARIES…WHY?
GAS EXCHANGE
 GAS EXCHANGE IN HUMANS
 WHERE ARE THE LUNGS IN ALL OF THIS?
 THE LUNGS ARE THE SACS THAT CONTAIN ALL OF THESE
STRUCTURES
 THEY ARE
SURROUNDED
BY A SPECIAL
MEMBRANE
CALLED THE
PLEURA
GAS EXCHANGE
 GAS EXCHANGE IN HUMANS
 HOW DOES THE AIR GET IN AND OUT OF THE LUNGS?
 B
R
E
A
T
H
I
N
G
GAS EXCHANGE
 GAS EXCHANGE IN HUMANS
 BREATHING
 DIAPHRAGM
 LONG FLAT
MUSCLE THAT
CONTROLS
INHALATION &
EXHALATION
GAS EXCHANGE
 GAS EXCHANGE IN HUMANS
 IN SUMMARY
 BREATHING
 EXTERNAL RESPIRATION (GAS EXCHANGE IN LUNGS)
 INTERNAL RESPIRATION (CELLULAR RESPIRATION)
GAS EXCHANGE
 GAS EXCHANGE IN HUMANS
 DISORDERS/DISEASES OF THE RESPIRATORY SYSTEM
 ASTHMA
 BRONCHITIS
 EMPHYSEMA
 PNEUMONIA
 LUNG CANCER
GAS EXCHANGE
 RANDOM REVIEW QUESTION…
HOW DO PLANTS PERFORM GAS EXCHANGE??
 STOMATES & GUARD CELLS!!!
GAS EXCHANGE
 HARD TO BELIEVE, BUT
WHEN YOU EXHALE THAT
HAS SOMETHING IN
COMMON WITH WHEN
YOU URINATE…
 WHAT COULD THAT BE?
COME BACK TO CLASS TO
FIND OUT…EXCRETION
IS NEXT!!