Midterm II -- Ch. 10 - Photosynthesis

Question 1

Metabolic Pathways

Answer 1

a series of chemical reactions that either builds a complex molecule (anabolic pathway) or breaks down a complex molecule to simpler molecules (catabolic pathway).

Question 2

Catabolic Pathway

Answer 2

a series of chemical reactions that break down a complex molecule into simpler molecules.

Question 3

Anabolic Pathway

Answer 3

a series of chemical reactions that build a complex molecule.

Question 4

Photosynthesis

Answer 4

the conversion of light energy to chemical energy that is stored in sugars or other organic compounds; occurs in plants, algae, and certain prokaryotes.

Question 5

Autotrophs

Answer 5

“self-feeders” – don’t eat anything derived from other human beings.

Question 6

Heterotrophs

Answer 6

live on compounds produced by other organisms.

Question 7

Mesophyll

Answer 7

leaf cells specialized for photosynthesis.

Question 8

Stomata

Answer 8

microscopic pores where CO2 enters and O2 leaves the plant.

Question 9

Stroma

Answer 9

the dense fluid within the chloroplast surrounding the thylakoid membrane and containing ribosomes and DNA; involved in the synthesis of organic molecules from CO2 and H2O.

Question 10

Thylakoid

Answer 10

a flattened membranous sac inside a chloroplast.

Question 11

Chlorophyll

Answer 11

green pigment that gives plants their color.

Question 12

Light reactions

Answer 12

convert solar energy to the chemical energy of ATP and NADPH, releasing oxygen in the process; 1st of two major stages in photosynthesis.

Question 13

Calvin cycle

Answer 13

2nd of two major stages in photosynthesis; fixation of atmospheric CO2 and reduction of the fixed carbon into carbohydrates.

Question 14

NADP+

Answer 14

an electron acceptor that, as NADPH, temporarily stores, energized electrons produced during the light reactions.

Question 15

Photophosphorylation

Answer 15

process of generating ATP from ADP and phosphate by means of chemiosmosis.

Question 16

Carbon fixation

Answer 16

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

Question 17

Wavelength

Answer 17

distance between the crests of electromagnetic waves.

Question 18

Spectrometer

Answer 18

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

Question 19

cartenoid

Answer 19

accessory pigment in the chloroplasts of plants.

Question 20

photosystem

Answer 20

light-capturing unit located in the thylakoid membrane of the chloroplast or in the membrane of some prokaryotes.

Question 21

reaction-center complex

Answer 21

complex of proteins associated with a special pair of chlorophyll a molecules and a primary electron acceptor.

Question 22

light-harvesting complex

Answer 22

a complex of proteins associated w/ pigment molecules that captures light energy and transfers it to reaction-center pigments in a photosystem.

Question 23

primary electron acceptor

Answer 23

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

Question 24

photosystem II (PS II)

Answer 24

one of two light-capturing units in a chloroplast’s thylakoid membrane or in the membrane of some protists.

Question 25

photosystem I (PS I)

Answer 25

light-capturing unit in a chloroplast’s thylakoid membrane or in the membrane of some protists.

Question 26

linear electron flow

Answer 26

a route of electron flow during the light reactions of photosynthesis that involves both PS I and PS II and produces ATP, NADPH, and O2.

Question 27

cyclic electron flow

Answer 27

a route of electron flow during the light reactions of photosynthesis that involves only PS I and produces ATP

Question 28

glyceraldehyde 3-phosphate (G3P)

Answer 28

a 3-C carbohydrate that is the direct product of the calvin cycle.

Question 29

rubisco

Answer 29

RuBP carboxylase, the enzyme that catalyzes the 1st step of the Calvin cycle.

Question 30

C3 plants

Answer 30

plant that uses the Calvin cycle for the initial steps that incorporate CO2 into organic material, forming a 3-C compound.

Question 31

photorespiration

Answer 31

metabolic pathway that consumes O2 and ATP releases CO2, and decreases photosynthetic output.

Question 32

bundle-sheeth cells

Answer 32

in C4 plants, type of photosynthetic cell arranged into tightly packed sheaths around the veins of a leaf.

Question 33

PEP carboxylase

Answer 33

enzyme that adds CO2 to PEP to form an oxaloacetate in mesophyll cells of C4 plants; acts prior to photosynthesis.

Question 34

CAM

Answer 34

adaption for photosynthesis in arid conditions; plant takes up CO2 and incorporates it into a variety of organic acids at night.