Cell Energy by liaoqinmei


									Cell Energy

    ATP, Photosynthesis, and
The Energy Molecule- ATP
   Energy in the body is used to maintain
   Homeostasis- maintaining a constant
    internal environment even though
    external conditions change
Examples of Homeostasis
   Body temperature regulation

                 When it is cold we shiver

When it is hot we sweat
Examples of Homeostasis
   Glucose
    in the
The Energy Molecule- ATP
   ATP is the molecule in the body that
    stores energy in the bonds between
    phosphate groups. When a bond
    between the phosphate groups is
    broken, energy is released.
The Energy Molecule- ATP
   Parts of an ATP molecule
       ATP stands for the molecule adenosine
       ATP contains one base, one sugar, and 3
        phosphate groups

         Base-adenine   Sugar-   P   P   P
The Energy Molecule-ATP
   ADP- Adenosine Diphosphate- 2
    phosphate groups
     Base-adenine     Sugar-     P       P

   AMP – Adenosine Monophosphate – 1
    phosphate group
       Base-adenine     Sugar-       P
       The Energy Molecule-ATP
            Cycling of ATP

                              ATP gains a
ATP loses a                   phosphate
phosphate-energy              through cellular
is released                   respiration-stores
The Energy Molecule-ATP
   Producers like plants, algae and some

   Plants trap energy from the sun, and
    build glucose molecules

   Light energy is converted to chemical
   Pigments                   chloroplast

   Light is absorbed by pigments in the
    chloroplasts called chlorophyll.
    Chlorophyll is a green pigment that
    absorbs most wavelengths of light.
   Other pigments include the colors red,
    orange, and yellow.
   Overall reaction for photosynthesis
                      Energy, light,
                      & chlorophyll
   6 CO2 + 6 H2O                     C6H12O6 +   6O2
     Photo synthesis
   2 phases of photosynthesis
       The light-dependent reaction
       The light-independent reaction (dark reaction)
   Light-dependent reaction
   Light is converted to ATP, a form of
    chemical energy
   The electron transport chain is when
    electrons from light are passed from
    one protein to another. Small amounts
    of energy are released along the way
    that convert ADP to ATP.
    Light-Dependent Reaction


                                 ATP &
                Electron         H+
                 Chain     Products go to
                           Reaction   
   Light-independent reaction (dark
   ATP is converted to glucose
   The Calvin Cycle is a series of reactions
    that use CO2 to form carbohydrates,
    mainly glucose.
 Light-Independent Reaction
ATP & H+

           Calvin Cycle   Glucose
      Summary of Photosynthesis
            H2O                   CO2

Light &              ATP & H+    Dark
           Light                           Glucose
enzymes   Reaction              Reaction

             O2                   H2O
Cellular Respiration
   Cellular Respiration
   Process of breaking down food
    molecules to produce energy (ATP)
Cellular Respiration
   Types of respiration

       Aerobic respiration requires oxygen

       Anaerobic respiration uses no oxygen
Cellular Respiration
   3 stages of aerobic respiration
       Glycolysis
       Citric acid cycle
       Electron transport chain
Cellular Respiration
   1. Glycolysis- Glucose, a six carbon
    sugar, is broken down into 2 molecules
    of pyruvic acid, a 3 carbon molecule.
       2 ATP used, 4 ATP made or gained,
        therefore there is a net gain of 2 ATP.
       This reaction does not use oxygen and is
        therefore an anaerobic process.
       This reaction occurs in the cytoplasm
Cellular Respiration
   Pyruvic acid now moves to the
    mitochondria where aerobic respiration
    can take place.
   2. Citric Acid Cycle (Kreb’s cycle)
       Pyruvic Acid is broken down to release CO2
        and 2 ATP.
Cellular Respiration
   Electron Transport Chain

       Oxygen is used to make water and 32
         Cellular Respiration
   Overall Reaction for Aerobic Respiration

    C6H12O6 +          6O2      6 CO2 +           6

       NOTE: Photosynthesis is the opposite reaction of
        respiration. The reactants of one are the
        products of the other.
Cellular Respiration
Cellular Respiration
   Anaerobic Respiration – 2 types

       Lactic Acid Fermentation

       Alcoholic Fermentation
Cellular Respiration
   Lactic Acid Fermentation- occurs when
    oxygen is scarce.

       Pyruvic acid is converted into 2 molecules
        of lactic acid and 2 molecules of ATP.

       Lactic Acid causes muscle fatigue in the
    Cellular Respiration
   Alcoholic fermentation- organisms like yeast
    and bacteria use this process to produce
    energy without the use of oxygen

       Pyruvic acid is converted to ethyl alcohol, carbon
        dioxide and 2 ATP

       When yeast is used to make bread, the carbon
        dioxide causes bubbles to form in the dough.
        Cellular Respiration Summary
        Anaerobic                  Glucose
    In                             Glycolysis                            In
cytoplasm                         Pyruvic acid                     mitochondrion
                                     2 ATP          Kreb’s Cycle
                                                       2 ATP

   Lactic Acid     Alcoholic
                                                 Electron Transport
  Fermentation   Fermentation
                                                       32 ATP

 Lactic Acid     Ethyl Alcohol,
   2 ATP          CO2, 2 ATP                        36 ATP, CO2
                                                      & H2 O
              Summary of Respiration
Characteristic   Starting    1st step   Uses     Cell location   Products    Number     Net Gain
                 materials              oxygen                               of ATP     of ATP

Aerobic          Glucose     Glycolysis Yes      Mitochondria CO2, H2O,       38 ATP    36 ATP
Respiration                                                   energy

Lactic Acid      Glucose     Glycolysis No       Cytoplasm       Lactic       4 ATP      2 ATP
Fermentation                                                     acid, ATP

Alcoholic        glucose     Glycolysis No       cytoplasm       Ethyl        4 ATP      2 ATP
Fermentation                                                     alcohol,
                                                                 CO2, ATP
    Comparison of Photosynthesis
    and Respiration
Characteristics          Photosynthesis         Aerobic Respiration

Reactants/requirements   CO2, H20, light,       Glucose, O2
                         chlorophyll, enzymes

Products                 Glucose, O2            CO2, H20, 36 ATP

Location                 chloroplasts           mitochondria

Use of energy            storage                release

Use of food molecules    Food made              Food broken down

To top