POINT > Define cell respiration POINT > Describe the two stages of respiration POINT > Show the equation for respiration POINT > Compare respiration with photosynthesis POINT > Describe two types of fermentation

POINT > Define cell respiration In respiration cells use oxygen (O 2 ) to get energy from carbohydrates (like glucose) The energy contained in glucose is released in a form the cell can use for many functions (ATP) Remember that the energy in glucose came from the sun during photosynthesis

POINT > Describe the two stages of respiration The first stage of respiration is called glycolysis Glycolysis happens in the cytoplasm and does not require oxygen

POINT > Describe the two stages of respiration During glycolysis glucose is split into two smaller molecules, releasing some energy as ATP. The cell can use ATP for many functions

POINT > Describe the two stages of respiration The second stage of respiration is more complex. This takes place in the mitochondria and requires oxygen. This is where most energy is released.

POINT > Describe the two stages of respiration The second stage of respiration is more complex. The molecules left from glycolysis diffuse into the mitochondria and enter the Krebs cycle:

POINT > Describe the two stages of respiration The second stage of respiration is more complex. The Krebs cycle produces more ATP and releases carbon dioxide (CO 2 )

POINT > Describe the two stages of respiration Molecules produced in the Krebs cycle enter more reactions that produce lots of ATP This is why the mitochondria are the “powerhouse” of the cell

POINT > Show the equation for respiration The equation for respiration: C 6 H 12 O 6 + 6O 2  6CO 2 + 6H 2 O + energy Glucose + oxygen  carbon dioxide + water + energy (ATP) Does this equation look familiar?

POINT > Compare respiration with photosynthesis The equation for photosynthesis: 6CO 2 + 6H 2 O  C 6 H 12 O 6 + 6O 2 The equation for respiration: C 6 H 12 O 6 + 6O 2  6CO 2 + 6H 2 O + energy The energy from the sun is changed into ATP for the cell!  ATP

POINT > Compare respiration with photosynthesis The products of photosynthesis C 6 H 12 O 6 + 6O 2 are the reactants for respiration: C 6 H 12 O 6 + 6O 2  6CO 2 + 6H 2 O + energy

POINT > Describe two types of fermentation If there is no oxygen, most of the energy in glucose is lost. Some cells can get a little energy from glucose using fermentation. There are two types of fermentation...

POINT > Describe two types of fermentation Alcoholic fermentation: yeast and/or bacteria cells use glucose to produce alcohol and CO 2. This is used for making bread,, beer and wine. The holes in bread and bubbles in beer are caused by carbon dioxide release

POINT > Describe two types of fermentation Lactic acid fermentation: When muscle cells run out of oxygen they can get some energy from glucose and produce lactic acid through fermentation This is used to make cheese and yogurt

Homework: Read pages S.A. page 94 #1-2 GRAS pages 47-49