2.9 Photosynthesis Flashcards
Photosynthesis
Process through which solar light energy is captured by chlorophyll and converted into chemical bond energy stored in organic molecules using water and carbon dioxide
Which is the shortest and longest wavelength in visible light spectrum?
Shortest= violet Longest = red
What are the wavelengths our eyes can detect?
Between 400-700nm
Chloroplast
An organelle that contains chlorophyll (green pigment) and traps light energy
Where is chloroplast located?
Mesophyll cells and guard cells
Which is the primary pigment?
Chlorophyll A
Which light does chlorophyll A absorbs most and least effectively?
Absorbs red and blue most effectively. Doesn’t absorb green light at all
What light does chlorophyll A reflect?
Green
Difference between absorption and action spectrum
Absorption: Shows which wavelength is absorbed by a particular photosynthetic pigment
Action: Shows efficiency of rate of photosynthesis at each wavelength in visible spectrum
Which peak is higher in absorption spectrum: blue or red?
Blue as it’s absorbed more
Accessory pigments
Allows some plants to take advantage of green wavelength. Beneficial for underwater plants
Why do leaves turn brown in the fall?
Active chlorophyll has accessory pigments that cannot be seen but when temperatures cool, those pigments are broken down and hence shown
Photolysis
Stage of photosynthesis where water is split by light
What does 2H2O+energy in photons give?
4e-, 4H+ and O2
Where do the electrons, H ions and O2 go after photolysis?
Electrons and hydrogen ions are used later in photosynthesis, oxygen is a waste product that diffuses out
