Unit 4: Energy Processes Flashcards Preview

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Flashcards in Unit 4: Energy Processes Deck (18):
1

mesophyll

tissue in the interior of the leaf in which chloroplasts are mainly found

2

stomata

microscopic pores on a leaf. Allow CO2 to enter and oxygen to exit

3

veins

deliver water from roots to leaves and export sugar from leaves

4

chlorophyll

a green pigment that resides in thylakoid membranes of plants
-absorbs light energy

5

Formula of Photosynthesis

6CO2+ 6H20+Energy -- C6H1206+ 6O2
-endergonic

6

light reactions

the steps of photosynthesis that convert solar energy to chemical energy (ATP and NADPH)
-water is split, providing electrons, H+, and 02
-absorbed light drives the transfer of electrons and H+ from water to NADP+

7

Calvin Cycle

carbon is fixated, incorporated into an organic molecule, Calvin cycle adds electrons, reducing fixed carbon to a carbohydrate
-occurs in the stroma

8

Light used in photosynthesis

380nm to 750 nm (visible light) drive photosynthesis
-chlorophyll absorbs violet-blue and red light, reflects green

9

photons

discrete particles of light, explains many of light's properties
-shorter the wavelength, the greater the energy of each wavelength

10

pigments

substances that absorb light

11

chlorophyll a

pigment that participates directly in light reactions

12

chlorophyll b

an accessory pigment, broadens the spectre of colors that can by used for photosynthesis

13

carotenoids

a group of accessory pigments
-hydrocarbons, that are usually yellow or orange
-absorb and dissipate excessive light energy which could cause damage

14

photosystem

composed of a reaction-center complex surrounded by several light-harvesting complexes

15

reaction-center complex

an organized association of proteins holding a special pair a special pair of chlorophyll molecules
-in PSII; P680 pigments
-in PSI- P700 pigments

16

light harvesting complex

-various pigment molecules bound to proteins

17

Linear Electron Flow

flow of electrons through the photosystems and other molecular components built into the thylakoid membrane

18

Cyclic Electron Flow

an electron path that uses PSI but not PSII
-electrons cycle back fro the primary accpetor, to ferredoxin, to the cytochrome complex, to plastocyanin
-their is no production of NADPH or O2 but does release ATP