Snacking on the Sun!

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Photosynthesis!

• Snacking on the Sun!

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Energy and Living Things

• Energy flows through living systems.

Energy flows from autotrophs (organisms that make
their own food) to heterotrophs (organisms that
rely on others for food).
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• Process by which light energy (from the sun) is
  converted into chemical energy (energy we can
  use).
• Almost all autotrophs are photosynthetic
  organisms like plants.

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PHOTOSYNTHESIS

• Occurs in the chloroplasts of plant cells by a
  chemical called chlorophyll.

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Chemical Equation of Photosynthesis

• 6CO2 6H2O C6H12O6 6O2
• Carbon dioxide from the air and water from the
  ground energy from sunlight a molecule of
  sugar and oxygen gas.

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PHOTOSYNTHESIS
So during photosynthesis..

• Plants take in
• 1. Carbon Dioxide
• 2. Water
• 3. Sunlight

And produce 1. Oxygen 2. Sugar (glucose)
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PHOTOSYNTHESIS

• 2 steps
• 1. Light Dependent Step
• 2. Light Independent Step aka the Calvin Cycle

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Light Dependent Step

• Energy captured from the sun is converted and
  stored as ATP.
• This is called the light dependent reaction
  because sun must be shining for this to happen.

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Light Independent Step(Calvin Cycle)

• The ATP from step 1 is used to make sugars
  (glucose) that the plant can use.
• This part, called the Calvin Cycle, is the light
  Independent reaction because it can occur at
  night without the sun.

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PHOTOSYNTHESIS

• Question So, now that plants have made sugar
  (glucose) from sunlight what do they do with it?

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PHOTOSYNTHESIS

• The same thing your body does with the sugar
  (glucose) it takes in by eating food!
• Answer It turns it into energy your cells can
  use (ATP) through a process called Cellular
  Respiration!!!!

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Cellular Respiration

• So, no matter if you ate it or made it from
  sunlight, creatures take sugar (glucose) and turn
  it into ATP through a process called CELLULAR
  RESPIRATION.

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Cellular Respiration

• Cellular respiration releases the energy in food
  to make ATP.
• Remember! ATP is a molecule that stores energy in
  a way that cells can actually use!

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Cellular Respiration

• This process occurs in the mitochondria (remember
  this organelle was our powerhouse or energy
  maker).

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Cellular Respiration

• C6H12O6 6O2 6CO2
  6H2O
• This equation is the exact same as the equation
  for photosynthesis, except..?

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Cellular Respiration

• C6H12O6 6O2 6CO2
  6H2O
• This equation is the exact same as the
• equation for photosynthesis, except..?
• Its reversed!

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Cellular Respiration
So, in Cellular Respiration ..

• Cells take in
• 1. Oxygen
• 2. Sugar (glucose)

Cells produce 1. Carbon dioxide 2. Water 3. ATP
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Cellular Respiration

• 3 Stages
• 1. Glycolysis
• 2. Krebs Cycle
• 3. Electron Transport Chain

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Cellular Respiration

• ANAEROBIC RESPIRATION- when you work out too much
  or get physically tired, your cells do not get
  enough oxygen. This causes them to go through a
  process called fermentation.

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2 Types of Fermentation

1. Lactic acid fermentation lactic acid is what
   makes your muscles burn.
2. Alcoholic Fermentation process by which beer
   and wine are made.

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Cellular Respiration

• There are 2 types
• 1. Aerobic requires oxygen
• 2. Anaerobic does not require oxygen.