Campbell Biology Chapter 10

Front 1

Photosynthesis

Back 1

The conversion of light energy to chemical energy that is stored in sugars or other organic compounds

Hint 1

 occurs in plants, algae, and certain prokaryotes.

Front 2

Autotrophs

Back 2

Organisms that sustain themselves without eating anything derived from other living beings. They use energy from the sun or from oxidation of inorganic substances to make organic molecules

Front 3

Heterotrophs

Back 3

An organism that obtains organic food molecules by eating other organisms or substances derived from them.

Front 4

Mesophyll

Back 4

Leaf cells specialized for photosynthesis.

Front 5

stoma(ta)

Back 5

Microscopic pore(s) surrounded by guard cells in the epidermis of leaves and stems that allows the exchange of gases

Front 6

stroma

Back 6

The dense fluid within the chloroplast surrounding the thylakoid membrane and containing ribosomes and DNA. involved in the synthesis of organic molecules from carbon dioxide and water

Front 7

thylakoid(s)

Back 7

A flattened, membranous sac inside a chloroplast. Thylakoids often exist in stacks called grana that are interconnected; their membranes convert light energy to chemical energy.

Front 8

Chlorophyll

Back 8

The green pigments that gives leaves their color, residing in the thylakoid membranes of chloroplasts

Front 9

Light Reactions

Back 9

The first of two major stages in photosynthesis (preceding the Calvin cycle). These rxns convert solar energy to the chemical energy of ATP and NADPH, releasing oxygen in the process

Front 10

The Calvin Cycle

Back 10

The second of two major stages in photosynthesis (following the light reactions), involving fixation of atmospheric CO2 and reduction of the fixed carbon into carbohydrate.

Front 11

Photo-phosphorylation

Back 11

The process of generating ATP from ADP and phosphate by means of chemiosmosis. using a proton-motive force generated across the membrane of the chloroplast or the membrane of certain prokaryotes during the light reactions of photosynthesis.

Front 12

Carbon Fixation

Back 12

The initial incorporation of carbon from CO2 into an organic compound by an autotrophic organism

Front 13

wavelength

Back 13

The distance between the crests of electromagnetic waves

Front 14

Electromagnetic Spectrum

Back 14

The entire spectrum of electromagnetic radiation, ranging in wavelength from less than a nanometer to more than a kilometer

Front 15

"Visible Light" spectrum

Back 15

That portion of the electromagnetic spectrum that can be detected as various colors by the human eye, ranging in wavelength from about 380 nm to about 750 nm

Front 16

Photons

Back 16

A discrete quantity of light energy that behaves as if it were a particle.

Front 17

Spectrophotometer

Back 17

An instrument that measures the proportions of light of different wavelengths absorbed and transmitted by a pigment solution.

Front 18

Absorption Spectrum

Back 18

A graph plotting a pigment's light absorption versus wavelength

Front 19

Chlorophyll a

Back 19

The key light-capturing pigment that participates directly in the light rxns

Front 20

Chlorophyll b

Back 20

An accessory photosynthetic pigment that transfers energy to chlorophyll a.

Front 21

action spectrum

Back 21

A graph that profiles the relative effectiveness of different wavelengths of radiation in driving a particular process

Front 22

Carotenoids

Back 22

hydrocarbons that are various shades of yellow and orange because they absorb violent and blue-green light

Front 23

A photosystem

Back 23

A light-capturing unit located in the thylakoid membrane of the chloroplast, consisting of a reaction-center complex surrounded by numerous light-harvesting complexes

Front 24

light harvesting complex

Back 24

A complex of proteins associated with pigment molecules (including chlorophyll a, chlorophyll b, and carotenoids) that captures light energy and transfers it to reaction-center pigments in a photosystem

Front 25

primary electron acceptor

Back 25

a specialized molecule that shares the reaction-center complex with a pair of chlorophyll a molecules and that accepts an electron from them.

Front 26

Photosystem ll

Back 26

One of two light-capturing units in a chloroplast’s thylakoid membrane that cooperate in the light rxns of photosynthesis

Hint 26

occurs 1st, but was discovered last

Front 27

photosystem l

Back 27

A light-capturing unit in a chloroplast’s thylakoid membrane or in the membrane.occurs after photosystem ll

Front 28

Linear electron flow

Back 28

A route of electron flow during the light reactions of photosynthesis that involves both photosystems (I and II) and produces ATP, NADPH, and O2. 

Front 29

Cyclic electron flow

Back 29

An alternative path of electron flow that photoexcited electrons use, where they go through photosystem l but not photosystem ll

Front 30

glyceraldhyde 3-phosphate (G3P)

Back 30

A 3 carbon sugar that is produced directly from the Calvin cycle

Front 31

Rubisco

Back 31

The enzyme that normally catalyzes the first step of the Calvin cycle 

Front 32

C3 plants

Back 32

A plant that uses the Calvin cycle for the initial steps that incorporate CO2 into organic material

Front 33

photorespiration

Back 33

A metabolic pathway that consumes oxygen and ATP, releases carbon dioxide, and decreases photosynthetic output. 

Front 34

C4 plants

Back 34

A plant in which the Calvin cycle is preceded by reactions that incorporate CO2 into a four-carbon compound, the end product of which supplies CO2 for the Calvin cycle

Front 35

Bundle-sheath cell

Back 35

In C4 plants, a type of photosynthetic cell arranged into tightly packed sheaths around the veins of a leaf. Co2 is released and enters the calvin cycle from this cell

Front 36

CAM (crassulacean acid metabolism)

Back 36

In this process, a plant takes up CO2 and incorporates it into a variety of organic acids at night; during the day, CO2 is released from organic acids for use in the Calvin cycle