Animal and Plant Gas Exchange How animals and plants get the gases they need

 ANIMAL SYSTEMS There’s two types of respiration that animals do. One is breathing, the other is cellular. Plants do the cellular one, but not the breathing one.

What’s the diff??  Internal Respiration  AKA cellular respiration!  Mitochondria  O2 is converted into CO2  Glucose is converted into ATP  This happens in the cells!

What’s the diff??  External Respiration  Breathing in and out  O2 is sucked in by the nose and mouth  O2 travels to lungs where the blood trades it for CO2  CO2 is breathed out as a waste from Cellular Respiration!

Structures of Respiratory System  Nose and Mouth  Breathe in and out  Trachea  Air flow travels through this tube  Lungs  Alveoli (air sacs) are the sight of gas exchange

Breathing

So what’s the point?  Function:  To breathe in O2 (for cellular respiration)  To exchange O2 for CO2  To get rid of (breathe out) CO2  SO…. We do external respiration (breathing) to have reactant gas (O2) for internal respiration (cellular respiration) and to get rid of the waste product (CO2)

How does gas exchange work in Respiratory System?  Tiny blood vessels called capillaries bring blood around the alveoli sacs to exchange gases

What do we need to breathe for?  OXYGEN intake!  CARBON DIOXIDE removal!  We have to breathe so that we can do cellular respiration!!!!  What happens to the CO2 we get rid of???  THINK…PLANTS duh!

RECAP

Questions  What is the difference between the respirations?  Why do we need to have Oxygen?  What happens to the CO2 we breathe out?  What structures actually do the gas exchange?  AND THE BIG QUESTION…  Do you think plants have a way to do gas exchange?  Do you think it works the same way??

Plant System Gas Exchange  PLANTS DON’T BREATHE!!!!  They do cellular respiration, but not the lung one!  They need to have a way to get CO2 and get rid of O2  The Answer??  A LEAF!!

What’s in a Leaf?  Leaf cross section

What’s in a Leaf?  Instead of a mouth for breathing, leaves have stomata  Pores in the underside of the leaf for gas to flow in and out  Also for water to leave!

Stomata  Also called stoma  Holes in the leaf  Guarded by cells that control how wide the pore is (Guard Cells)  Important for gas movement  AND WATER loss!

Transpiration  Plant sweating  On wet days, the cells are swollen with water and they bend, opening the stomata pore  On dry days, they are thin and straight, closing off the stomata pore

But why would it ever close?  Plants lose too much water if they stay open  But they don’t get enough CO2 in if they’re closed….hmmm  So when would be a good time for them to be closed?

How does gas travel in a plant?  Travels through the spongy mesophyll to get to the palisade mesophyll (where photosynthesis occurs)

So what’s the point?  Why do plants need CO2?  Why do they need to get rid of O2?  What happens to the O2?  What else is ‘leafing’ out of the plant besides O2?

Gas Travel  So the respiratory system in animals is for gas exchange….  How does this compare to the plant system?  What do these both need gas for?

A COMPARISON  Explain how the respiratory system in animals is comparable to the gas exchange system in plants.  Make sure you look at structures, functions, importance.  Work as a group.