4.1 Chemical Energy and ATP
All cells need chemical energy
Cell Energy = ATP
ATP = Adenosine Triphosphate
4.1 Chemical Energy and ATP
• ATP transfers energy from the breakdown of food molecules to cell functions.
– Energy is released when a phosphate group is removed.
– ADP – adenosine diphosphate
– ADP is changed into ATP when a phosphate group is added.
adenosine
triphosphate
tri=3
adenosine
di=2
diphosphate
4.1 Chemical Energy and ATP
Molecules in food store chemical energy in their bonds
Starch molecule
Glucose molecule
4.1 Chemical Energy and ATP
• Fats store the most energy.
– 80 percent of the energy in your body
– about 146 ATP from a triglyceride
• Proteins are least likely to be broken down to make ATP
4.1 Chemical Energy and ATP
Heterotrophs – rely on other sources for E
Autotroph - manufacture own food
• most use photosynthesis
– converts sunlight into chemical E
– chemical E is stored in the form of sugars
4.1 Chemical Energy and ATP
A few autotrophs do not need sunlight and photosynthesis as a source
of energy.
• live in places that never get sunlight.
• Chemosynthesis
– uses chemical E (S) instead of light E
to make food
– Chemosynthetic bacteria –
hydrothermal vents
4.1 Chemical Energy and ATP
4.1
Chemicalof
Energy
and ATP
4.2 Overview
Photosynthesis
Photosynthetic organisms are autotrophs = producers
•
•
•
•
Photosynthesis captures E from sunlight to
make food – sugar
Glucose
All sugars end in -ose
2 phases of photosynthesis
1. light-dependent reactions
2. light-independent reactions
4.1
Chemicalof
Energy
and ATP
4.2 Overview
Photosynthesis
1. Visible spectrum – wavelengths the human eye can see
2. different colors have different wavelengths
3. Pigment - absorb specific wavelengths of light
crest
I----------------------------I
wavelength
Trough
4.1
Chemicalof
Energy
and ATP
4.2 Overview
Photosynthesis
Why are Leaves Green?
• http://www.youtube.com/watch?v=aAQYpra4aUs&list=PL
ElB7nLNHZvhSor-RW0mv1FE_IDi9ZuiA&index=9
4.1
Chemicalof
Energy
and ATP
4.2 Overview
Photosynthesis
Chloroplast contains pigments to capture light
• Chlorophyll - reflects green light & absorb all others
• Carotenoids – reflect orange light & absorbs all others
• Anthocyanine – reflect purples and red light & absorbs all others
4.1 Chemical Energy and ATP
4.1
Chemical
Energy
and ATP
4.2 Overview
4.3
Photosynthesis
of
Photosynthesis
in Detail
The light-dependent reactions
– chlorophyll absorbs E from sunlight
– Photolysis – water molecules are split
– H2O  H + O
– Takes place in the thylakoids (grana)
– Increase surface area to increase amount of H2O split
– Oxygen is released as waste
4.1
Energy
and ATP
4.3 Chemical
Photosynthesis
in Detail
The light-independent reactions
– Takes place in the Stroma – space between the thylakoids
– needs carbon dioxide (CO2) from atmosphere
– Calvin cycle - Carbon fixation
– Use E and H from light dependent reaction to build a 6 carbon chain
of sugar (glucose)
– C6H12O6
4.1
Energyinand
ATP
4.3.Chemical
Photosynthesis
Detail
• Sugar can be used, or stored as starch, and some is built into cellulose
• We obtain E from plants by eating the stored sugar
• http://ed.ted.com/lessons/the-simple-but-fascinating-story-ofphotosynthesis-and-food-amanda-ooten
4.1
Energy
and ATP
4.3 Chemical
Photosynthesis
in Detail
• The equation for the overall process is:
6CO2 + 6H2O  C6H12O6 + 6O2
granum (stack of thylakoids)
1
chloroplast
6H2O
6O2
2
thylakoid
energy
stroma (fluid outside the thylakoids)
6CO2
1 six-carbon sugar
C6H12O6
3
4
4.1 Chemical Energy and ATP
Light Dependent
Light Independent
4.1 Chemical Energy and ATP
4.4
Cellular
Respiration
4.1 Overview
Chemicalof
Energy
and
ATP
1. Glycolysis - splits glucose into two molecules of
pyruvate (pyruvic acid)
– C-C-C-C-C-C  C-C-C + C-C-C
– Produces some ATP molecules
– Takes place in cytoplasm
4.4
Cellular
Respiration
4.1 Overview
Chemicalof
Energy
and
ATP
2. Aerobic Respiration
With O2
1. Glycolysis
2. Anaerobic Respiration
Without O2
(Fermentation)
4.4
Cell Respiration
4.1 Overview
Chemicalof
Energy
and ATP
Aerobic Respiration – with Oxygen
1. The Krebs cycle – Citric Acid Cycle
– takes place in
mitochondrial matrix
– breaks down pyruvic acid
– makes a small amount of ATP
– releases carbon dioxide
1
mitochondrion
ATP
matrix (area enclosed
by inner membrane)
and
6CO 2
Krebs Cycle
energy
2
3
energy from
glycolysis
inner membrane
ATP
and
and
6O 2
6H 2O
4
4.5
Respiration
in Detail
4.1 Cellular
Chemical
Energy and
ATP
Aerobic Respiration
2. The Electron Transport Chain
• takes place on the cristae
• Makes a large amount of ATP
• Water is released as a waste product
4.5
4.4
Overview
Respiration
of
Cell Respiration
in Detail
4.1 Cellular
Chemical
Energy
and
ATP
• The equation for the overall process is:
C6H12O6 + 6O2  6CO2 + 6H2O
• The reactants in Photosynthesis are the same as the products of Cellular
Respiration
• The reactants in Cellular Respiration are the same as the products of
Photosynthesis
4.6 Fermentation
13.1 Ecologists Study Relationships
Anaerobic Respiration:
Two Types
1. Lactic Acid Fermentation
2. Alcoholic Fermentation
4.6 Fermentation
4.1 Chemical Energy and ATP
•
Lactic acid fermentation occurs in muscle cells.
1. Glycolysis – Glucose  Pyruvate
2. Converts pyruvate  lactic acid
– Muscle pain and weakness
4.6 Fermentation
4.1 Chemical Energy and ATP
Alcoholic fermentation
1. Glycolysis – Glucose  Pyruvate
2. Split pyruvate  ethyl alcohol and carbon dioxide
-
Yogurt, cheese, bread
4.1 Chemical Energy and ATP
4.1 Chemical Energy and ATP
Extra Credit
• Create an alphabet picture book for middle school kids with ideas
relating to cell biology
• Due: Thursday Oct 17th