Lecture 8-Photosynthesis

Question 1

autotrophs

Answer 1

use inorganic carbon as C source to fix C into organic compound

Question 2

photoautotroph

Answer 2

use light energy to fix C

Question 3

chemoautotroph

Answer 3

use redox energy to fix C

Question 4

heterotrophs

Answer 4

use organic C as both C source and energy source

Question 5

chemoheterotrophs

Answer 5

use organic C as main nutirent

Question 6

photoheterotroph

Answer 6

use light energy and organic C

Question 7

where does light reactions occur

Answer 7

thylakoid membrane

Question 8

where does calvin cycle occur

Answer 8

stroma

Question 9

redox reaction of photosynthesis

Answer 9

carbon dioxide is reduced and water is oxidized to produce oxygen and glucose

Question 10

function of light reactions

Answer 10

use energy carried by light and convert it into chemical energu in the form of ATP and NADPH that will be used to power the calvin cycle

Question 11

what happens to the light that is absorbed?

Answer 11

-absorbed by pigments and used as energy source

Question 12

photosystems function

Answer 12

sit in thylakoid membrane and contain pigments to absorb light
-pigments within the photsystem can absorb light, excite e-, and pass those e- thru the photosystem

Question 13

ETC (election transport chain)

Answer 13

a set of increasing strength of e- acceptors to allow energy from excited e- to be converted into H gradient and released in small discrete steps

Question 14

three methods of energy conversion

Answer 14

1. convert light energy into chem. energy in the form of an excited e-
   2.excited e- is passed down ETC and releases energy to pump H into thylakoid gradient
2. excited e- from P1 is used to reduce NADP+

Question 15

chemiosmosis

Answer 15

formation of ATP using a H concentration gradient and ATP synthase

Question 16

photophosphorylation

Answer 16

if energy source for H gradient is light

Question 17

oxidative phosphorylation

Answer 17

if energy source for H gradient is oxidation of a nutirent

Question 18

ATP synthase

Answer 18

an enzyme complex that couples ATP synthesis (endergonic) with the dissipation of H gradiant (exergonic)

Question 19

what is NADPH?

Answer 19

an election carrier b/w redox reaction of light reactions to calvin cycle
-electon is used to reduce C

Question 20

calvin cycle/dark reaction function

Answer 20

to fix C from atmospheric form to organic C
-use energy from light reactions (ATP and NADPH) to convert CO2 to sugar
-endgergonic

Question 21

carbon fixation phase of calvin cycle

Answer 21

one CO2 is added per turn of cycle therefore the cycle must turn three times to get one product (G3P)
-enzyme=rubisco

Question 22

reduction phase of calvin cycle

Answer 22

the NADPH from light reactions are used to reduce the fixed C

Question 23

regeneration phase of calvin cycle

Answer 23

RuBP is regenerated
-a set of complex rxns requiring ATP

Question 24

net inputs of calvin cycle

Answer 24

9 ATP, 6 NADPH, 3 CO2= 1 G3P

Question 25

cyclic electron flow in the light reactions function

Answer 25

to make ATP using light rxn componenets without making NADPH in order to account for difference needed for calvin cycle
-e-is recycled back to the ETC to pump H and contribute to the H conc. gradient that is used to make ATP
-phosphorylation