CP 6 Photosynthesis

Question 1

what is the spectrum of visible light

Answer 1

400nm-700nm

Question 2

light behaves like a ___ and like _______ of energy (photons)

Answer 2

wave, particles

Question 3

TF short wavelengths = low energy, long wavelengths = high energy

Answer 3

F, the opposite

Question 4

how does light interact with matter

Answer 4

it can:
- reflect off
- transmit through
- absorbed by

Question 5

to be used as energy, light must be ____

Answer 5

absorbed

Question 6

how is light absorbed

Answer 6

• Energy of photon is transferred to
  an electron within a molecule
• Energy transfer switches electron
  from grounded state to excited
  state

Question 7

what is a pigment

Answer 7

molecules that absorb
photons of specific wavelengths

Question 8

if in object it red it means that red is ___ and the other colours are ___

Answer 8

reflected, absorbed

Question 9

what is an autotroph

Answer 9

Organisms that make required organic molecs from inorganic sources such as CO2 and water

Question 10

what is a photoautotroph

Answer 10

Autotrophs that use light as the energy source to make organic molecules by photosynthesis

Question 11

what is a heterotroph

Answer 11

Consumers and decomposers, which need source of organic molecules to survive

Question 12

TF photosynthesis is a formation reaction

Answer 12

F, its Redox

Question 13

what are the 2 stages of photosynthesis

Answer 13

Light reactions
Calvin Cycle

Question 14

what is the light reactions step in photosynthesis

Answer 14

• ## Pigment molecules capture light energy and its used to synthesize both ATP and NADPH

Question 15

what is the calvin cycle step in photosynthesis

Answer 15

NADPH and ATP used to fix CO2 into carbohydrates (glucose)

Question 16

what is the aqueous environment of a chloroplast called

Answer 16

stroma

Question 17

what is granum/granum

Answer 17

stacks of thylakoids

Question 18

what 3 things eventually happen to an excited electron

Answer 18

• returns to its ground state, releasing energy as heat or as light
• Energy from excited electron in one pigment molecule is transferred to a neighboring pigment molec
• Excited-state electron itself is transferred to nearby electron-accepting molecule

Question 19

what do carotenoids and chlorophylls do when absorbing light

Answer 19

act in combination, drives
reactions of photosynthesis

Question 20

what is the main feature of the photosystem

Answer 20

Pigments bound precisely in thylakoid
membrane to specific proteins

Question 21

what is a photosystem

Answer 21

Large antenna complex (light harvesting
complex) of pigments that surrounds reaction
centre

Question 22

how does a photosystem work

Answer 22

• Acts as light funnel to chlorophyll A
• Moves it from 1 pigment molec to another
• Then gives an electron to the electron transport carriers to oxidize chlorophyll A

Question 23

what is the difference in absorbtion between photosystem 1 and 2

Answer 23

• PS2 absorption max = 680nm
• PS1 absorption max = 700nm

Question 24

what do PS1 and PS2 have in common

Answer 24

both have specialized chlorophyll A in reaction centre

Question 25

what are the steps in the photosynthetic electron transport path

Answer 25

- PS2 --> cytochrome complex (plastoquinone) - cytochrome --> PS1 (plastocyanin) - PS1 --> NADP+ (ferredoxin Stroma side) - NADP+ --> reduced to NADPH - PS1 reduced to ground state - PS2 reduced to ground state

Question 26

what carrier is used to get the product of PS2 to the cytochrome complex

Answer 26

plastoquinone

Question 27

what carrier is used to get the product of the cytochrome complex to the PS1

Answer 27

plastocyanin

Question 28

what carrier is used to get the product of PS1 to the NADP+

Answer 28

Ferredoxin stroma side

Question 29

who is the final electron acceptor in the Photosynthetic Electron Transport path

Answer 29

NADP+

Question 30

how does PS2 return to ground state

Answer 30

using H2O

Question 31

how does PS1 return to ground state

Answer 31

using electrons from PS2

Question 32

how is ATP produced after electrons go thru the electron transport path (Chemiosmotic Synthesis of ATP)

Answer 32

Hydrogens that were released from the PS2 and the plastoquinone are taken by the ATP synthase molec at the end of the chain and produces the ATP

Question 33

how does the cyclic electron transport cycle work

Answer 33

- Ferrodoxin donates electrons to plastoquinone (PQ) - Redox of PQ and PQ pool keeps moving protons across thylakoid membrane without involvement of photosystem 2

Question 34

what are the 3 steps to the calvin cycle

Answer 34

- Fixation - Reduction - Regeneration

Question 35

what is fixation in the calvin cycle

Answer 35

CO2 added to RuBP to produce 6 PGA molecule

Question 36

what is reduction in the calvin cycle

Answer 36

- NADPH and ATP are used to convert 6 PGA into 6 G3P (higher energy molecule used to build sugar) - 1 GP3 released, other 5 move to next step

Question 37

what is regeneration in the calvin cycle

Answer 37

Remaining 5x G3P molecules are used to recreate RuBP

Question 38

what is RuBisCo

Answer 38

- most abundant protein on earth - provides organic carbon for earths oraganisms

Question 39

whats the difference between photosynthesis and cellular respiration

Answer 39

- Photosynthesis = ATP produced via light energy (photophosphorylation) and used to make organic molecules - Cell respiration = ATP produced by breaking down organic molecules (oxidative phosphorylation)

Question 40

what is the relationship between photosynthesis and cellular respiration

Answer 40

Photosynthesis and cell respiration are in many respects the reverse of one another

Question 41

Photosynthesis is an _____process Cell respiration is a _____process

Answer 41

anabolic catabolic