11.2 light dependent photosynthesis

Question 1

two purposes of the light dependent reaction

Answer 1

• to add Pi molecule to ADP to make ATP
  -split water into H+ ions and OH- ions by photolysis-caused by light

Question 2

oxidation

Answer 2

-loss of electrons
-loss of hydrogen
-gain of oxygen

Question 3

reduction

Answer 3

-gain of electrons
-gain of hydrogen
- loss of oxygen

Question 4

what does oxidation result in?

Answer 4

energy being taken in

Question 5

first step of light dependent reaction

Answer 5

chlorophyll absorbs light energy into photosystem 2 which excites electrons

Question 6

second stage of light dependent reaction

Answer 6

excited electrons leave the chlorophyoll in a process called photoionisation

Question 7

third stage of the light dependent reaction

Answer 7

the electrons that leave the chlorophyll are taken up by a molecule called an electron carrier

Question 8

fourth stage of the light dependent reaction

Answer 8

chlorophyll is oxidized due to lost electrons, electron carriers which have gained electrons have become reduced

Question 9

fifth step of light dependent reaction

Answer 9

-electrons pass through electron transport chain in the thylakoid membrane in number of oxidation reduction reactions
-electrons loose energy at each stage
-some of this energy is used to combine Pi with ADP to make ATP

Question 10

sixth stage of light dependent reaction

Answer 10

mechanisms by which ATP is produced as explained by chemiosmotic theory

Question 11

first step of chemiosmotic theory

Answer 11

each thylakoid is an enclosed chamber into which H+ protons are pumped from the storm using protein carriers in the thylakoid membrane called proton pumps

Question 12

second step of chemiosmotic theory

Answer 12

the energy to drive this process is from electrons which are released from water molecules split by photolysis

Question 13

Third step of chemiosmotic theory

Answer 13

the photolysis of water also produces protons which further increases their concentration inside the thylakoid space

Question 14

fourth step of chemiosmotic theory

Answer 14

overall this creates and maintains a concentration gradient of protons across the thylakoid membrane with a high concentration inside the thylakoid space with a low concentration in the stroma

Question 15

fifth step of chemiosmotic theory

Answer 15

protons can only cross the thylakoid membrane through ATP synthase channel proteins
-the rest of the membrane is impermeable to protons

Question 16

NADPH

Answer 16

an electron carrier involved in photosynthesis which provides electrons to Calvin cycle

Question 17

chloroplasts

Answer 17

organelle where photosynthesis takes place

Question 18

thylakoid

Answer 18

sac like photosynthetic membranes found in chloroplasts where light dependent reaction takes place

Question 19

stroma

Answer 19

fluid portion of the chloroplast; outside of the thylakoids where light independent reactions occur

Question 20

granum

Answer 20

a stack of thylakoids where photosystems 1 and 2 are located

Question 21

palisades mesophyll

Answer 21

the upper layer of photosynthetic tissue in a leaf. the majority of photosynthesis happens here.

Question 22

stomata

Answer 22

smal openings on the underside of a leaf through which oxygen and carbon dioxide can move