Cell Process Photosynthesis

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Cell Process Photosynthesis

Cell Process - Photosynthesis

Photosynthesis is used to build carbohydrates (the main energy source of all life.) - - Producers (like plants)

use carbon dioxide and water to make carbohydrates; oxygen gas is released as waste - - Occurs in the chloroplasts - - {Write Equation}

Chloroplast Structure - Stroma is the space between the grana which are stacks of tylakoid membranes which are full of pigments (quick pic)

Figure 7.2

Photosynthetic Pigments ? chemicals such as chlorophyll that absorb various portions of visible light. (Anything green denotes chlorophyll and is photosynthetic. Chlorophyll is great at absorbing all colors except green. Green is reflected, which is why it looks green to our eyes.)

1. Two major photosynthetic pigments are chlorophyll a and chlorophyll b. 2. Both chlorophylls absorb violet, blue, and red wavelengths best.

3. Most green is reflected back; this is why leaves appear green.

Accessory pigments help absorb the light colors that chlorophyll can't. - Carotenoids are yelloworange pigments which absorb violet, blue, and green regions. - Phycobilins are red-purple pigments - When chlorophyll breaks down and is reabsorbed in fall, it is pulled out of the leaves first. This allows the accessory pigments in

leaves show through.

Absorption Spectrum - spectrophotometer measures the amount of light that passes through a sample of pigments (like crushed green leaves)

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