All cells need energy to function, which they obtain through glucose. Autotrophic cells produce their own glucose through photosynthesis using sunlight, carbon dioxide, and water. Heterotrophic cells obtain glucose through other means. Glucose is converted to ATP through cellular respiration, releasing energy. Photosynthesis uses chlorophyll and other pigments to convert sunlight, carbon dioxide and water into glucose and oxygen through a series of chemical reactions in chloroplasts. Cellular respiration breaks down glucose and oxygen in mitochondria to produce water, carbon dioxide, and ATP.

1. Cellular Ener g y
Needs
Biology
Mr. Hildebrandt

2. All Living Cells Need
Energy
 Cells either make
their own food
(glucose) or obtain it.
 Autotrophic cells
convert sunlight into
glucose
 Heterotrophic cells
have to obtain
glucose by other
means.

3. Energy Storage
Molecules
 Glucose is turned
into energy storage
molecules called
ATP.
 ATP = Adenosine
Triphosphate
 When a phosphate
group is broken off,
energy is released

4. Chemical Reactions
 Reactants – substances that enter a
reaction. They are changed.
 Products – substances left after the
reaction has taken place.
 Two chemical reactions are
necessary for cells to produce
energy: Photosynthesis & Cellular
Respiration

6. Photosynthetic
Pigments
 Pigments are chemicals
that absorb light.
 Chlorophyll (A and B)
Primary pigments, green
in color.
 Anthocyanin – red/purple
 Carotene – orange
 Xanthophyll - yellow

7. Photosynthesis
Explained
 Takes place in
Chromoplasts within
autotrophic cells.
 Primarily the
Chloroplasts
 Reactants: Carbon
Dioxide & Water
 Products: Glucose &
Oxygen
 Driven by the sun

8. light
6CO 2 + 6H 2 O C 6 H 12 O 6 + 6O 2

9. Cellular Respiration
Explained
 Process that releases energy (ATP)
by breaking down glucose
 Takes place in cells
mitochondria
 Reactants: glucose
& oxygen
 Products: H20, CO2
& ATP

10. Types of Cellular
Respiration
 Aerobic (sufficient O2) – very effective, 36
ATPs produced from one glucose:
C6H12O6 + 6O2 6CO2 + 6H20 + 36 ATP
 Fermentation (no O2) – not efficient
1. Alcoholic Fermentation: alcohol
and C02 are produced
2. Lactic Acid Fermentation: l. acid
produced