Exam 3: Photosynthesis

Question 1

photosynthesis

Answer 1

the process by which light energy is converted into chemical energy

Question 2

mesophyll

Answer 2

the chlorplastic parenchyma tissue where photosynthesis occurs; located between the two outer tissues of the leaf

Question 3

bundle-sheath cell

Answer 3

photosynthetic cells packed into tight sheaths that protect leaf veins

Question 4

mesophyll cell

Answer 4

photosynthetic cells associated with bundle sheath cells;

Question 5

stoma

Answer 5

a pore formed by two guard cells in the epidermis of a plant that allows for gas exchange

Question 6

thylakoid

Answer 6

a membrane-bound compartment where the light-dependent reactions of photosynthesis take place; form stacks called grana

Question 7

stroma

Answer 7

the colorless liquid found within a chloroplast that surrounds the grana

Question 8

chlorophyll

Answer 8

a green pigment found in plant cells that allows plants to collect light energy for use in photosynthesis

Question 9

carotenoid

Answer 9

a yellow-orange pigment found in plant cells that absorb blue light for use in photosynthesis

Question 10

electromagnetic spectrum

Answer 10

the range of frequencies of electromagnetic radiation, starting with short gamma waves and ending with long radio waves

Question 11

wavelength

Answer 11

the distance between each repeat of the wave’s shape

Question 12

absorption spectrum

Answer 12

the variation in the amount of light absorbed at different wavelengths

Question 13

action spectrum

Answer 13

the variation in how effective light is at driving photosynthesis at different wavelengths

Question 14

visible light

Answer 14

the range of electromagnetic radiation that is visible to human eye

Question 15

photon

Answer 15

the basic unit of light; contains energy utilized in photosynthesis

Question 16

spectrophotometer

Answer 16

measures wavelengths of length

Question 17

photosystem

Answer 17

protein complex containing light-absorbing pigments where photosynthesis takes place

Question 18

photosystem I (PS I)

Answer 18

a protein complex that uses light energy to synthesize NADPH; contains an antenna complex and a reaction center

Question 19

photosystem II (PS II)

Answer 19

a protein complex that uses light energy to synthesize ATP; contains an antenna complex and a reaction center

Question 20

light-harvesting complex (antenna complex)

Answer 20

part of the photosystem; contains chlorophyll and carotenoid pigments

Question 21

reaction center

Answer 21

contains two chlorophyll a molecules that absorb light

Question 22

chlorophyll a

Answer 22

a photosynthetic pigment that serves as a primary electron donor in the electron transport chain

Question 23

chlorophyll b

Answer 23

– a photosynthetic pigment found only in plants and green algae

Question 24

light reaction

Answer 24

the first step in photosynthesis where light energy is converted to chemical energy; takes place on the thylakoid membrane

Question 25

electron transport chain

Answer 25

facilities the conversion of light energy (sunlight) into chemical energy in photosynthesis by transferring electrons from a donor to an acceptor and generating ATP

Question 26

NADP+

Answer 26

the last molecule in the electron transport chain of the light reactions; used to create a proton gradient in chloroplasts

Question 27

primary electron acceptor

Answer 27

accepts the electron from chlorophyll and donates it to the electron transport chain

Question 28

photophosphorylation

Answer 28

the synthesis of ATP using light energy transported through the electron transport chain

Question 29

cyclic electron flow

Answer 29

an electron transport pathway that produces ATP without NADPH; associated with photosystem I

Question 30

noncyclic electron flow

Answer 30

an electron pathway where electrons travel one-way from H2O to NADP+

Question 31

ATP synthase

Answer 31

a membrane-spanning protein complex that uses the transport of protons across the membrane to produce ATP

Question 32

proton gradient

Answer 32

a difference in potential on either side of the plasma membrane created by the active transport of protons through proton pumps

Question 33

potential energy

Answer 33

energy stored in matter as a result of its position or configuration; can be used to do work

Question 34

Calvin Cycle (light-independent reaction)

Answer 34

the second step of photosynthesis where electrons are used to convert inorganic CO2 into organic CO2

Question 35

carbon fixation

Answer 35

the transformation of inorganic atmospheric CO2 into organic molecules (e.g.: glucose)

Question 36

glyceraldehyde-3-phosphate (G3P)

Answer 36

produced during the Calvin cycle from two molecules of GP (which were produced in the first step of the light-independent reactions)

Question 37

photorespiration

Answer 37

metabolic process where RuBP has O2 added instead of CO2

Question 38

RUBISCO

Answer 38

enzyme that catalyzes reaction of RuBP with either O2 or CO2 in the first step of carbon fixation

Question 39

CAM plant

Answer 39

uses the crassulacean acid metabolism (CAM) pathway to produce CO2 for the Calvin cycle; both processes occur in the mesophyll, but at a different time of day; adapted to surviving in dry, hot conditions

Question 40

C3 plant

Answer 40

depends on the light-independent reactions of photosynthesis (Calvin cycle); cannot grown in hot areas

Question 41

C4 plant

Answer 41

uses a C4 pathway to fix CO2 into oxaloacetate and produce CO2 for the Calvin cycle