Energy
Types of energy
Chemical
Kinetic
Heat
Electrical
Light
Adenosine Triphosphate
Made of an adenosine molecule with 3 phosphate groups attached to
By breaking the bond between the 2nd and 3rd phosphate, energy becomes available for all cellular processes
Accessory pigments
Capture light that chlorophyll cannot
Carotinoids- Yellow-orange pigments; absorb violet, blue, and green regions
Xanthophylls- red and yellow pigments; do not absorb light as well
Anthocyanins- purple or blue pigments absorb green light
What happens in the fall? Accessory pigments are always in plants, chlorophyll is more abundant during warmer weather
In fall chlorophyll breaks down, other pigments show
Light dependent
Light energy is absorbed and splits water to create ATP and energy carrier molecules
Produces oxygen and ATP
Uses water to produce oxygen
Occurs in the thylakoids
Where does energy come from?
Chemical energy is a form of potential energy stored in chemical bonds of food molecules
When bonds are broken energy is released
Energy from the broken bonds of glucose are converted into high energy bonds in ATP molecules
ATP provides energy (gasoline) for chemical reactions in the cell
Sources of ATP for living organisms
Autotrophs- Make their own food using energy in sunlight (some use chemicals)
Suns energy is converted into bonds of glucose within the chloroplasts of plant cells
Heterotrophs- Must consume other organisms for food
Energy from glucose is converted into the bonds of ATP within the mitochondria of the cell
Photosynthetic pigments
Major light absorbing pigments in thylakoid membrane are chlorophyll a and chlorophyll b
Both absorb violet, blue, and red wavelengths best
Most green is reflected back
What is energy?
The ability to do work
Can be transformed from one type of energy to another
Work done by living things - Breaking down and building molecules, moving things in and out of the cell, cell division
Chloroplast structure
Stroma- fluid filled inner space
Thylakoids- internal disklike membranes within stroma, organized into stacks called grana, embedded with special proteins called pigments
Equipment needed for obtaining the raw materials of photosynthesis
Leaves- to take in the sunlight
Chloroplasts-solar collectors containing pigments and energy carriers molecules
Stomata- structures with holes on the bottom of leaves to take in CO2 and releases O2 and water
Roots- water uptake