KEY%20CONCEPT%20All%20cells%20need%20chemical%20energy.

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KEY CONCEPT All cells need chemical energy.
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• The cells of all organismsfrom algae to whales
  to peopleneed chemical energy for all of their
  processes.
• Some organisms, such as diatoms and plants,
  absorb energy from sunlight. What is a diatom?
• What do they do with it?
• Some of that energy is stored in sugars.
• Cells break down sugars to produce usable
  chemical energy for their functions.

• Without organisms that make sugars, living things
  on Earth could not survive.

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• MAIN IDEA The chemical energy used for most cell
  processes is carried by ATP.
• You are hungry. You need energy, so you grab
  what? A Snickers Bar? A Kit-Kat Bar?
• Does this food that contains sugar and other
  Carbon-based molecules give you the energy that
  you need? How does it provide it to you,
  exactly?
• All carbon-based molecules store chemical energy
  in their bonds!

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• Molecules in food store chemical energy in their
  bonds.

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What is ATP?Adenosine triphosphate, a molecule
that transfers energy from the breakdown of food
molecules to cell processes.

• ATP carries chemical energy that cells can use.
• Cells use ATP to carry out functions
• building molecules
• moving materials by active transport.

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• How does ATP transfer energy from the breakdown
  of food molecules to cell functions?

• ATP has three phosphate groups, but the third has
  a unstable, weak bond.
• Energy is released when the third phosphate group
  is removed.
• ADP is changed into ATP when a phosphate group is
  added.

ADP is a lower-energy molecule that can be
converted into ATP by the addition of a phosphate
group.
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Describe the relationship between energy stored
in food and ATP.

• Food molecules store chemical energy in their
  bonds.
• Food is broken down into smaller molecules that
  are broken down further to transfer this energy
  to ATP.

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Organisms break down carbon-based molecules to
produce ATP.

• Food does not contain readily useable ADP that
  our cells can use.
• Food has to be eaten and digested first (making
  smaller molecules)
• Different foods contain different amounts of
  calories, which is a measure of energy. Calories
  and ATP are related.
• Different foods contain different amounts of ATP.
• The number of ATP molecules produced depends on
  the type of molecule that is broken down
• Carbohydrate
• Lipid
• Protein

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• Carbohydrates are the molecules most commonly
  broken down to make ATP.

• not stored in large amounts in our bodies
• you can get up to 36 ATP molecules from one
  glucose molecule

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• Lipids or Fats store the most energy and provide
  the most ATP when broken down.

• Store 80 percent of the energy in your body
• Obtain about 146 ATP molecules from a triglyceride

• Proteins are least likely to be broken down to
  make ATP.

• amino acids not usually needed for energy, but
  for making new proteins!
• store about the same amount of energy as a
  carbohydrate

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A few types of organisms do not need sunlight and
photosynthesis as a source of energy.

• Some organisms live in places that never get
  sunlight (hydrothermal vents)
• These vents release chemical compounds
• In chemosynthesis, organisms use chemical energy
  instead of light energy to make energy-storing
  carbon-based molecules.
• Process is
• similar to photosynthesis
• uses chemical energy instead of light energy