Transcript ATP and Chemical Energy

ATP and Chemical Energy
1
Objectives
• SWBAT recognize the importance of ATP as an
energy-carrying molecule.
• SWBAT identify energy sources used by
organisms.
2
Review Vocabulary
•
•
•
•
•
•
Glucose
Carbohydrate
Monosaccharide
Polysaccharide
Starch
Cellulose
3
What is this molecule?
• What is this molecule?
– C6H12O6
• Who makes it?
• Why is it important?
4
Glucose is the building block
• Glucose is linked together to make all sorts of
different macromolecules (molecules that are
really big) like starch and cellulose.
These are 2 glucose
molecules joined to
make a molecule
known as table sugar
5
Vocabulary
• ATP
• ADP
• Homeostasis
• Triglyceride
• Glucose
Review Vocabulary If Needed
• Carbohydrate
• Monosaccharide
• Polysaccharide
• Starch
• Cellulose
6
SciShow: ATP and Cellular Respiration
• https://www.youtube.com/watch?v=00jbG_cf
GuQ
7
Energy and Food
• When we need energy, we eat.
– The foods we eat are carbon-based molecules –
carbohydrates, starches, proteins, lipids, etc.
• The question then is, how does food give you
energy?
8
Energy and Food
• Before energy can be extracted from food, it
has to be broken down (energy comes food
but not directly). There is no ATP in the food
you eat.
• All the carbon-based molecules in food
contain energy in their bonds.
– This energy is useable only when those bonds are
broken and the energy is released.
– Carbohydrates and lipids are the most important
energy sources in the food you eat.
9
Bonds need to be broken
• Molecules in food store chemical energy in
their bonds – breaking the bonds frees energy.
Starch molecule
Glucose molecule
10
ATP - Currency of Cellular Energy
• ATP transfers energy from the breakdown of food
molecules to cell functions.
– Energy is released when a phosphate group is removed.
– ADP is changed into ATP when a phosphate group is
added.
phosphate removed
Energy from breaking the
carbon and other bonds in
the food you eat.
Energy is released when a
phosphate is removed from the
ATP molecule.
11
ATP - Currency of Cellular Energy
• ATP is chemical energy that is available to the
cell to power its necessary functions.
– Your cells use ATP to move materials by active
transport, exocytosis, and endocytosis.
– They also use ATP to create molecules such as
proteins, lipids, nucleic acids, and any other
molecule they need in order to function properly
(to maintain homeostasis).
12
ATP - Currency of Cellular Energy
Energy is released when a
phosphate is removed from the
ATP molecule.
Biosynthesis is
the production
of complex
molecules
within living
cells.
When the phosphate is
removed and energy released,
ATP becomes ADP.
13
ADP
• ADP is adenosine diphosphate.
– It is a lower-energy molecule than ATP.
– It can be converted into ATP by the addition of a
phosphate group.
This is a simplified version of the
cycle that turns ADP into ATP.
This process is not simple.
phosphate removed
14
ATP/ADP
15
Molecular Structure of ATP
Nucleoside
Ribose
16
Making ATP
• Digestion breaks down food into smaller
molecules (think glucose) that then can be
used to make ATP.
– Different foods have different amounts of calories,
which indirectly related with how much ATP each
type of food can make.
– Carbohydrates are the most commonly broken
down molecule to make ATP. The breakdown of
the simple sugar glucose yields about 38
molecules of ATP.
17
Making ATP
• The body does not store carbohydrates (it
burns them); however, the body does store
lipids.
– Lipids store about 80% of the energy in your body
– they are our fat stores.
– When broken down, they make about 146
molecules of ATP from one triglyceride (this is
why animals pack on the fat to survive periods
when there is very little food).
18
Making ATP
• Proteins are least likely to be broken down to make ATP.
– amino acids not usually needed for energy
– about the same amount of energy as a carbohydrate
19
Making ATP
Polar bears will go months without
eating (stranded on land) – living on
their fat until pack ice is formed and
they can hunt seals.
This is a wild polar bear who lives on
Hudson Bay (in Manitoba). While waiting
for the ice to form, this polar bear made a
friend – a sled dog. The bear visited the
dog on several occasions to play. When
the ice formed, the bear went on his way.
20