Respiration Converting and using energy

RespirationRespiration

Photosynthesis ReviewPhotosynthesis Review

► Photosynthesis Photosynthesis stored energy in the stored energy in the form of glucose. form of glucose. Glucose is what Glucose is what

animals and plants animals and plants use as their source of use as their source of energy.energy.

► But ATP is the usable But ATP is the usable energy in a cell…not energy in a cell…not glucose. So…glucose. So…

Respiration: What is it?Respiration: What is it?

►Essentially cellular respiration Essentially cellular respiration breaks food particles (glucose) breaks food particles (glucose) down into ATP.down into ATP.• ATP is the form of energy that cells ATP is the form of energy that cells

can use.can use.• Respiration provides all living things Respiration provides all living things

with the energy they need.with the energy they need.• This is aerobic respiration, which This is aerobic respiration, which

requires oxygen. requires oxygen.

Respiration: What is it?Respiration: What is it?

Respiration: Who does it?Respiration: Who does it?► All living things do All living things do

cellular respiration …cellular respiration …including plants.including plants.

Respiration: Where does it Respiration: Where does it happen?happen?

►Mitochondria of a cellMitochondria of a cell The “powerhouse” of the cellThe “powerhouse” of the cell Found in plants and animalsFound in plants and animals

Respiration:Respiration: How does is How does is happen?happen?

3 steps of respiration:3 steps of respiration:

1.1. Glycolysis:Glycolysis: Glucose broken down into smaller Glucose broken down into smaller

parts (2 molecules of Pyruvic Acid)parts (2 molecules of Pyruvic Acid) ATP producedATP produced

2.2. Citric Acid Cycle (Krebs Cycle):Citric Acid Cycle (Krebs Cycle): Pyruvic Acid is broken down into COPyruvic Acid is broken down into CO22

More ATP is produced.More ATP is produced.

Respiration:Respiration: How does is How does is happen?happen?

3 steps of respiration:3 steps of respiration:

3.3. Electron Transport Chain (ETC):Electron Transport Chain (ETC):

• Hydrogen is released Hydrogen is released and forms with oxygen and forms with oxygen to create water.to create water.

• More ATP is More ATP is producedproduced

Respiration:Respiration: How does is How does is happen?happen?

glucose + oxygen glucose + oxygen CO CO22 + water + water

respirationrespiration

photosynthesisphotosynthesis

Therefore the overall reaction of Therefore the overall reaction of cellular respiration is the cellular respiration is the reverse of photosynthesis:reverse of photosynthesis:

So what’s the moral of the So what’s the moral of the photosynthesis – respiration photosynthesis – respiration

story??story?? ITS ALL ONE BIG CYCLE!!ITS ALL ONE BIG CYCLE!!

NO TREES MEANS NO BREATHENO TREES MEANS NO BREATHE

Check your understandingCheck your understanding

1.1. How is respiration different than How is respiration different than photosynthesis, how are they the same?photosynthesis, how are they the same?

2.2. What is the definition of respiration?What is the definition of respiration?

3.3. Through what 3 steps does respiration Through what 3 steps does respiration produce ATP?produce ATP?

4.4. The cell of an organism that starved to The cell of an organism that starved to death is tested and found to have a high death is tested and found to have a high concentration of pyruvic acid. What failed? concentration of pyruvic acid. What failed?

Anaerobic respirationAnaerobic respiration

►Often referred to as fermentation (in yeast)Often referred to as fermentation (in yeast)►Does not require oxygen (ODoes not require oxygen (O22))

• Byproduct is alcoholByproduct is alcohol• Only happens in oxygen deprived environmentsOnly happens in oxygen deprived environments

- We had anaerobic respiration in our yeast lab! - We had anaerobic respiration in our yeast lab!

- Brewing- Brewing

• Does not produce as much ATP as aerobic Does not produce as much ATP as aerobic respiration, therefore plants and animals use respiration, therefore plants and animals use aerobic respiration whenever they can. aerobic respiration whenever they can.

Anaerobic respirationAnaerobic respiration

► In animal cells the product is Lactic AcidIn animal cells the product is Lactic Acid►Occurs during oxygen (OOccurs during oxygen (O22) stress) stress

• It leads to muscle fatigue in athletes.It leads to muscle fatigue in athletes.• Good cardio-vascular fitness can prevent Good cardio-vascular fitness can prevent

muscle fatigue.muscle fatigue.

Does not produce as much ATP as aerobic Does not produce as much ATP as aerobic respiration, therefore plants and animals use respiration, therefore plants and animals use aerobic respiration whenever they can. aerobic respiration whenever they can.