Final Exam

Front 1

"Life on Earth is Solar Powered" - explain

Back 1

All organisms are autotrophs or eat autotrophs

Front 2

Where is the action in plant?

Back 2

chloroplasts (filled with thykaloids)

Front 3

Explain the "lenses" in the epidermis?

Back 3

There are epidermal cells that act as lenses to focus light on the chloroplasts. chloroplasts surround the area where the light is most intense.

Front 4

Photosynthesis

Back 4

6CO2 + 12H2O + light --> C6H12O6 + 6O2 + 6H2O
~respiration backwards

Front 5

where does the oxygen come from?

Back 5

the water!

Front 6

Explain the cycle?

Back 6

ATP and NADPH from the light cycle enter the Calvin Cycle. ADP and NADP from calvin are transferred back to the light cycle to pick up H+
~light and dark reactions are paired together

Front 7

what color of light drived photosynthesis?

Back 7

red and purple

Front 8

explain the structure of chlorophyll

Back 8

the porphyrin ring is the light absorbing head of the molecule (looks like hemoglobin). the hydrocarbon tail anchors chlorophyll in the thykaloid membrane

Front 9

how a photosystem harvest light...noncylic e- flow
*electron is produced by slitting of water - this is where O2 comes from*

Back 9

light hits and excited an electron on photosystem II that flows to a primary electron acceptor. electron then flows down an e-transport chain. chemiosmosis produces ATP. light hits photosystem I and excited e- which flows down chain and converts NADP+ to NADPH.

Front 10

Cyclis Electron Flow

Back 10

electron goes around and around but always returns to Photosystem I. produce ATP by chemiosmosis.

Front 11

what connects photophosphoylation and the calvin cycle?

Back 11

ATP and NADPH from photophosphorylation enters the Calvin Cycle. photophosphorylation are the LIGHT REACTIONS.

Front 12

Calvin Cycle - Phase 1

Back 12

Phase 1: Carbon Fixation - produce 3PG. triggered by rubisco (most common enzyme)
ATP -> ADP

Front 13

Calvin Cycle - Phase 2

Back 13

Phase 2: Reduction
production of G3P, a sugar.
NADPH -> NADP + H

Front 14

Calvin Cycle - Phase 3

Back 14

Phase 3: Regeneration of RuBP
ATP -> ADP
-need the cyclic electron flow to provide ATP for this pahse

Front 15

What is the most important enzyme on earth?

Back 15

Rubisco!...provides the carbons that all hetertrophs eat. this molecule can fix CO2 but also can react with O2 in photorespiration.

Front 16

Photorespiration

Back 16

rubisco catalyzes a reaction between O2 and RuBP in addition to the rxn between CO2 and RuBP. Reduces photosynthesis by up to 50%
-problem on hot, dry days
-uses ATP
~on hot, dry days plants close stomates so CO2 level drops and rubisco seeks out O2.

Front 17

C4 Plants - one solution to photorespiration

Back 17

C4 plants fix CO2 into a 4-carbon acid which diffuses into bundle sheath cells. the decaroxylation produces locally high [CO2]
-Calvin Cycle is isolated from rest of leaf

Front 18

CAM Plants - another solution to photorespiration

Back 18

open stomates at night and collect CO2. Fix CO2 into C4 compound. stomates close during day and artificially keep [CO2] high

Front 19

How are photosynthesis and respiration related???

Back 19

the Calvin-Benson cycle, the citric acid cycle, and glycolysis

Front 20

Where did mitochondria and chloroplasts come from? (Both involved in chemiosmosis, 2 membranes, and similar organelles)

Back 20

endosymbiosis - were formerly prokaryotic cells living within larger cells. engulfed by eukaryotes