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.