8: Photosynthesis

Question 1

range of wavelengths of electromagnetic radiation absorbed by a given substance

Answer 1

absorption spectrum

Question 2

pigment molecule that directly absorbs light and transfers the energy absorbed to other pigment molecules

Answer 2

antenna protein

Question 3

light-independent reactions of photosynthesis that convert carbon dioxide from the atmosphere into carbohydrates using the energy and reducing power of ATP and NADPH

Answer 3

Calvin cycle

Question 4

process of converting inorganic CO2 gas into organic compounds

Answer 4

carbon fixation

Question 5

photosynthetic pigment (yellow-orange-red) that functions to dispose of excess energy

Answer 5

carotenoid

Question 6

organism that can build organic molecules using energy derived from inorganic chemicals instead of sunlight

Answer 6

chemoautotroph

Question 7

form of chlorophyll that absorbs violet-blue and red light and consequently has a bluish-green color; the only pigment molecule that performs the photochemistry by getting excited and losing an electron to the electron transport chain

Answer 7

chlorophyll a

Question 8

accessory pigment that absorbs blue and red-orange light and consequently has a yellowish-green tint

Answer 8

chlorophyll b

Question 9

organelle in which photosynthesis takes place

Answer 9

chloroplast

Question 10

group of reversibly oxidizable and reducible proteins that forms part of the electron transport chain between photosystem II and photosystem I

Answer 10

cytochrome complex

Question 11

range of all possible frequencies of radiation

Answer 11

electromagnetic spectrum

Question 12

group of proteins between PSII and PSI that pass energized electrons and use the energy released by the electrons to move hydrogen ions against their concentration gradient into the thylakoid lumen

Answer 12

electron transport chain

Question 13

stack of thylakoids located inside a chloroplast

Answer 13

granum

Question 14

organism that consumes organic substances
or other organisms for food

Answer 14

heterotroph

Question 15

complex that passes energy from sunlight to the reaction center in each photosystem; it consists of multiple antenna proteins that contain a mixture of 300 to 400 chlorophyll a and b molecules as well as other pigments like carotenoids

Answer 15

light harvesting complex

Question 16

first stage of photosynthesis where certain wavelengths of the visible light are absorbed to form two energy-carrying molecules (ATP and NADPH)

Answer 16

light-dependent reaction

Question 17

second stage of photosynthesis, through which carbon dioxide is used to build carbohydrate molecules using energy from ATP and NADPH

Answer 17

light-independent reaction

Question 18

middle layer of chlorophyll-rich cells in a leaf

Answer 18

mesophyll

Question 19

reaction center of photosystem II

Answer 19

P680

Question 20

reaction center of photosystem I

Answer 20

P700

Question 21

ejection of an electron from a reaction center
using the energy of an absorbed photon

Answer 21

photoact

Question 22

organism capable of producing its own
organic compounds from sunlight

Answer 22

photoautotroph

Question 23

distinct quantity or “packet” of light energy

Answer 23

photon

Question 24

group of proteins, chlorophyll, and other pigments that are used in the light-dependent reactions of photosynthesis to absorb light energy and convert it into chemical energy

Answer 24

photosystem

Question 25

integral pigment and protein complex in thylakoid membranes that uses light energy to transport electrons from plastocyanin to NADP+ (which becomes reduced to NADPH in the process)

Answer 25

photosystem I

Question 26

integral protein and pigment complex in thylakoid membranes that transports electrons from water to the electron transport chain; oxygen is a product of PSII

Answer 26

photosystem II

Question 27

molecule that is capable of absorbing certain wavelengths of light and reflecting others (which accounts for its color)

Answer 27

pigment

Question 28

pigment or other organic molecule in the reaction center that accepts an energized electron from the reaction center

Answer 28

primary electron acceptor

Question 29

complex of chlorophyll molecules and other organic molecules that is assembled around a special pair of chlorophyll molecules and a primary electron acceptor; capable of undergoing oxidation and reduction

Answer 29

reaction center

Question 30

gain of electron(s) by an atom or molecule

Answer 30

reduction

Question 31

instrument that can measure
transmitted light and compute the absorption

Answer 31

spectrophotometer

Question 32

opening that regulates gas exchange and water evaporation between leaves and the environment, typically situated on the underside of leaves

Answer 32

stoma

Question 33

fluid-filled space surrounding the grana inside a chloroplast where the light-independent reactions of photosynthesis take place

Answer 33

stroma

Question 34

disc-shaped, membrane-bound structure inside a chloroplast where the light-dependent reactions of photosynthesis take place; stacks of thylakoids are called grana

Answer 34

thylakoid

Question 35

aqueous space bound by a thylakoid membrane where protons accumulate during light-driven electron transport

Answer 35

thylakoid lumen

Question 36

distance between consecutive points of equal position (two crests or two troughs) of a wave in a graphic representation; inversely proportional to the energy of the radiation

Answer 36

wavelength