Energy in cells

ENERGY IN CELLS

Class notesMonday, October 4th, 2010

Where do we get our energy from?

• Food that we eat!• How did that food get its energy?• Cells take energy stored in food and change it

into different forms for all activities of life

Where does this energy in food come from?

• All of the energy comes from the sun: Solar energy!

• Plant cells– Absorbs the sun’s energy

and changes it into a form of energy that the plant can use

• We eat plants and other animals that eat plants– This is how we get our

energy!

Where does this process take place?

• Plants make their own food through PHOTOSYNTHESIS

• Plant cells have chloroplasts

• Chloroplasts contain chlorophyll (a green chemical) which traps the sun’s energy

PHOTOSYNTHESIS• Turning solar

energy into sugars

• Requires:– Carbon dioxide– Water– Light energy

RESPIRATION

• We must break down the food moleculesinto energy our cells can use

• This is called RESPIRATION

• Requires:– Oxygen – Sugars to break down

(food!)

Instructions: • You will be assigned to be a carbon (C ), hydrogen (H) or oxygen (O)

atom and we will act out the processes of photosynthesis and respiration

• Some students may also be the SUN and equals (arrow symbol: )

• PHOTOSYNTHESIS equation:

• RESPIRATION equation: