CELLS

1
CELLS ENERGY
Ch's 67

• Need energy to
• move
• change shape
• repair structure
• make new cell parts
• transport food
• expel wastes

2
Sun is ultimate source of energy
Autotrophs make own food
Heterotrophs eat other orgs
Energy is obtained through Biochemical Pathways
linked chemical reactions (product of one is
reactant of another)
3
2 Important Pathways
Photosynthesis- Light energy converted to
chemical energy of organic compounds
(carbs) Autotrophs only
Cellular Respiration- Organic compounds broken
down to produce energy in a form a chemical
compounds ATP Autotrophs Heterotrophs
4
PHOTOSYNTHESIS
6CO2 6H20 solar energy
C6H12O6 6O2

• Occurs in leaves where chloroplasts are abundant

5

• Plants contain pigments (compounds that absorb
  light)

• Chlorophyll reflects green light (green
  leaves) uses red blue

• Carotenoids reflect yellow, orange, brown
  (fruits/flowers)

6
CELLULAR RESPIRATION
C6H12O6 6O2
6CO2 6H2O energy
Process by which all organisms release energy
stored in organic molecules Connection between
photosynthesis and respiration
7
2 STAGES

1. In cytoplasm Glucose is broken down 2 smaller
   molecules result.
2. In mitochondria those 2 molecule combine to
   Oxygen to form CO2

8
Fermentation is a type of respiration in which
some organism converts a carbohydrate, such as
starch or a sugar, into an alcohol or an acid.
For example, yeast perform fermentation to obtain
energy by converting sugar into alcohol. Bacteria
perform fermentation, converting carbohydrates
into lactic