Lecture 20: Absorbtion and transfer of energy

Question 1

what are the major factors to sustain plant life

Answer 1

water, air, light/energy

Question 2

water

Answer 2

solvent for enzymatic activity and formation of biological membrane

Question 3

air

Answer 3

basic elements like C, O, and N

Question 4

electromagnetic spectrum

Answer 4

white light passes through a prism and is separated into the different color/wavelengths of light

Question 5

light

Answer 5

thermonuclear fusion generates ultimate form of energy in sun in the form of electromagnetic radiation

Question 6

visible spectrum

Answer 6

around 43% of the total radiant energy emitted from sun

Question 7

visible spectrum

Answer 7

400-700nm/main light to hit a leaf

Question 8

photosynthetically available (active) radiation

Answer 8

the portion of light that can be captured and used by photoautotrophs for photosynthesis

Question 9

what is light

Answer 9

light is a transverse electromagnetic wave that consists of oscillating electric and magnetic fields

Question 10

what speed does light move at

Answer 10

3x10^8 m/s

Question 11

short wavelength = ______ energy

Answer 11

high

Question 12

long wavelength = _______ energy

Answer 12

low

Question 13

photosynthetic action spectrum

Answer 13

magnitude of biological response to light
the rate of photosynthesis
a single wavelength of light in photosynthesis

Question 14

absorbtion spectrum

Answer 14

the amount of absorbed light by a molecule
functional wavelength of light in photosynthesis

Question 15

why do pigments capture the light

Answer 15

they get energy from the light

Question 16

what does light do to pigments

Answer 16

it puts them in an excited state

Question 17

photoexcitation outcomes

Answer 17

• heat
• Fluorescence
• energy transfer
• photochemistry

Question 18

photoexcitation outcomes: heat

Answer 18

thermal dissipation convert excitation energy to heat and chlorophylls return to ground state

Question 19

photoexcitation outcomes: fluorescence

Answer 19

immediate reemission of energy as a long wavelength

Question 20

photoexcitation outcomes: energy transfer

Answer 20

excited pigment molecule transfers its energy to another molecule

Question 21

photoexcitation outcomes: photochemistry

Answer 21

energy of the excited state triggers a chemical reaction and becomes a e- donor. Linkage of the excited e- donor to a proper e- acceptor. Transduction of chemical energy

Question 22

ground state

Answer 22

electrons occupy the lowest energy level before a photon of light strikes chlorophyll

Question 23

excited state

Answer 23

electrons gain energy when a photon hits a chlorophyll

Question 24

energy transfer during photosynthesis

Answer 24

is it a pure physical phenomenon with no chemical changes and resonance energy transfer

Question 25

resonance energy transfer

Answer 25

energy is transferred from pigment to pigment by resonance until it reaches the reaction center pigment

Question 26

Light-harvesting complex

Answer 26

pigments molecules bounded to proteins

Question 27

reaction center

Answer 27

special pair of chlorophyll a and electron acceptor

Question 28

photosystem

Answer 28

reaction center surrounded by several LHCs

Question 29

energy funnel

Answer 29

from antenna system to the reaction center

Question 30

what are the 2 photosystems that oxygen evolving organisms have

Answer 30

Photosystem 1 and 2

Question 31

emerson enhancement effect

Answer 31

2 photosystems must operate to drive photosynthesis most effectively

Question 32

what are photosystem 1 and 2 linked by

Answer 32

electron transport chain

Question 33

Z-scheme

Answer 33

cooperation of PS2 and PS1 in the transfer of electrons from water to NADP+