Light Reactions

Question 1

What does Redox mean?

Answer 1

Reduction-Oxidation

Question 2

What is oxidation-reduction (redox) reactions?

Answer 2

The redox reactions involve electrons passing from one molecule to another

Question 3

Oxidation is the _____________ of electrons while Reduction is the ______________ of electrons

Answer 3

loss; gain

Question 4

What are the tasks of ATP?

Answer 4

1. Chemical work: ATP is used for building macromolecules
2. Transport work: ATP is used for transporting ions membranes
3. Mechanical work: ATP is used for mechanical processes such as muscle contraction, cilia movement

Question 5

How do plants harness light energy to manufacture food?

Answer 5

Photosynthesis

Question 6

How do living organisms harness energy from food?

Answer 6

Cellular Respiration

Question 7

Formula of Photosynthesis

Answer 7

6CO2 + 6H20 -> C6H12O6 + 6O2

Question 8

Formula of Cellular Respiration

Answer 8

C6H12O6 + 6O2 -> 6CO2 + 6H20

Question 9

Plants are ____________. This term means “self-feeders” in Greek.

Answer 9

Autotrophs

Question 10

Autotrophs make their own food and thus sustain themselves without?

Answer 10

Eating other organisms or even organic molecules

Question 11

Plants are referred to as the ____________ of the biosphere

Answer 11

Producers

Question 12

Plants are not only the producers certain ________, _______, and ________ also make food molecules from inorganic materials

Answer 12

Bacteria, Archaea, Protists

Question 13

All organisms that use light energy to make food molecules are called?

Answer 13

Photosynthetic Autotrophs

Question 14

______, _____, and _____________________ all use light energy to drive the synthesis of organic molecules from carbon dioxide and water

Answer 14

Plants; Algae; Photosynthetic Bacteria

Question 15

All green parts of a plant have ____________ and can carryout photosynthesis

Answer 15

Chloroplasts

Question 16

In most plants, what part of the plant has the most chloroplasts?

Answer 16

The leaves

Question 17

The green color in plants comes from where?

Answer 17

Chlorophyll pigments in chloroplasts

Question 18

Chloroplasts are concentrated in the cells of the _________.

Answer 18

Mesophyll

Question 19

What is the definition of Mesophyll?

Answer 19

Mesophyll is defined as the green tissue in the interior of the leaf

Question 20

Carbon dioxide enters the leaf and the oxygen exits by way of tiny pores called?

Answer 20

The Stomata

Question 21

The chloroplasts’s inner membrane is filled with?

Answer 21

Stroma

Question 22

What is Stroma?

Answer 22

1. It is a thick fluid
2. It is where sugars are made from carbon dioxide and water

Question 23

What is Thylakoid?

Answer 23

1. It is suspended in the air
2. It is a system of dislike membranous sacks

Question 24

Grana are __________ that are concentrated in stacks

Answer 24

Thylakoids

Question 25

The thylakoid membranes house much of the machinery that converts _____ energy to ________ energy

Answer 25

Light; Chemical

Question 26

Sunlight is a type of energy called _________ or _________________________

Answer 26

Radiation; Electromagnetic Energy

Question 27

The distance between the crests of two adjacent waves is called?

Answer 27

Wavelength

Question 28

Light-absorbing molecules called pigments in the membranes of a granum absorb what color wavelengths?

Answer 28

Mainly Blue Violet and Red Orange

Question 29

Chlorophyll A absorbs mainly?

Answer 29

Violet and Red Orange light

Question 30

Does Chlorophyll A participate directly in the light reactions?

Answer 30

Yes

Question 31

Chlorophyll B absorbs mainly?

Answer 31

Blue and Orange light

Question 32

Does Chlorophyll B participate directly in the light reactions?

Answer 32

No

Question 33

Chloroplasts contains a family of yellow-orange pigments called ___________, which absorbs mainly blue-green light.

Answer 33

Carotenoids

Question 34

Carotenoids has a protective function that does what?

Answer 34

It absorbs and dissipates excessive light energy that would otherwise damage the chlorophyll

Question 35

What color of light is least effective in driving photosynthesis?

Answer 35

Green

Question 36

A ______ is a fixed quantity of light energy, and the shorter the wavelength, the greater the energy

Answer 36

Photon

Question 37

What happens when a pigment molecule absorbs a photon?

Answer 37

One of the pigment’s electrons gains energy and the electron has been raised from a ground state to an excited state.

Question 38

When illuminated, the chlorophyll emits heat and photons of light that produce a reddish after glow as electrons fall from excited state to the ground state. What is this afterglow called?

Answer 38

Fluorescence

Question 39

What are the two types of Photosystem?

Answer 39

Photosystem I and Photosystem II

Question 40

What is the reaction center in Photosystem I?

Answer 40

P700

Question 41

What is the reaction-center of Photosystem II?

Answer 41

P680

Question 42

Light reactions use ________ in order to initiate electron transfer

Answer 42

Sunlight

Question 43

Light reactions are used to?

Answer 43

Form ATP through phosphorylation

Question 44

Key events of the light reactions of photosynthesis are?

Answer 44

1. Absorption of Light Energy 2. Excitation of Electrons by Light Energy 3. Formation of ATP and NADPH using energy made available by the cascade of energized electrons down the electron transport chains

Question 45

What is the waste product of the light reactions?

Answer 45

O2

Question 46

What are the products of the light reactions?

Answer 46

NADPH, ATP, O2

Question 47

The synthesis of ATP is driven by what process?

Answer 47

Chemiosmosis

Question 48

There is a flow of electrons from ____________ molecules to _____________, which is reduced to __________, the source of electrons for sugar synthesis in the _________________ cycle.

Answer 48

Water, NADP+, NADPH, Calvin

Question 49

The chemiosmosis production of ATP is referred to as?

Answer 49

Phosphorylation

Question 50

Protons “want” to diffuse back down the gradient into the stroma, and their only route of passage is through the enzyme?

Answer 50

ATP Synthase

Question 51

Why does Cyclic Electron Flow exist?

Answer 51

1. When CO2 concentration is less in the atmosphere 2. When need for ATP outweighs the need for NADPH