kingdom plantae nutrition. photosynthesis- o the process of converting solar energy to chemical...
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Photosynthesis-
The process of converting solar energy to chemical energy
Used by green plants, algae, euglena, and the blue-green bacteria
6 CO2 + 6 H2O -------------> C6H12O6 + 6 O2
Carbon Water Glucose Oxygen dioxide
How we perceive color
Sunlight is a mixture of all visible wavelengths Objects appear a certain color because they are
reflecting that wavelength So when we look at green plants, red and blue
light is absorbed (used for photosynthesis) and green light is reflected
The visible spectrum
Light travels in particles that form waves
The shorter the wavelength the greater the available energy
Violet=the greatest energy Red=the lowest energy
Pigments-substances that absorb light
Photosynthetic pigments 1) chlorophyll a-primary photosynthetic pigment
2) chlorophyll b
3) carotenes-reflect orange light
4) xanthophylls-reflect yellow light
Chlorophyll a hides the other pigments
It is the first to break down in the fall when sunlight decreases and temperatures cool
This is why we see other colors in the fall
Chloroplasts-cell organelle containing photosynthetic membranes and pigments Thylakoids-”green disks”,
the photosynthetic membranes inside
Grana-stacks of thylakoids
Stroma-regions around the grana
Stroma
Thylakoids
Photosynthesis-
The process by which organic compounds (glucose) are synthesized in the presence of carbon dioxide and light
Factors affecting photosynthesis
1) light intensity-as intensity increases, rate of photosynthesis increases (to a certain point)
2) water-a deficiency will slow or stop photosynthesis
3) minerals, carbon dioxide, nutrients-a deficiency will slow or stop photosynthesis
4) temperature-this influences enzyme activity
Heterotrophic plants
Mistletoe-a parasitic plant It photosynthesizes but also
takes sap from the vascular tissue of host plants such as oaks
Heterotrophic plants con’t
Pitcher plants-photosynthetic but supplements missing nutrients in its environment with nitrogen from captured insects Venus flytrap does this too!
Plant Regulation
Remember the factors that affect photosynthesis? Plants need to regulate carbon dioxide intake and water
loss Leaves have pores called stomata
that let carbon dioxide in
and oxygen out
Stomata
If stomata are open, what is lost along with oxygen?
Water!!!!
So plants close stomata during times of high water loss (like hot, sunny days)