Chapter 6: Part 2 Photosynthesis

Question 1

All life forms require what?

Answer 1

They require an energy source and a carbon source

Question 2

What are the two types of carbon source?

Answer 2

1. Autotroph

2. Heterotroph

Question 3

Autotroph

Answer 3

An organism can make its own food from inorganic substances and it fixes carbon CO2

Question 4

Heterotroph

Answer 4

An organism that can’t produce its own food requires food from organic carbon (Consumers in the food chain)

Question 5

What are the two types of energy source?

Answer 5

1. Phototroph

2. Chemotroph

Question 6

Phototroph

Answer 6

An organism that captures energy from sun-light

Question 7

Chemotroph

Answer 7

An organism that uses either an organic or inorganic source of energy

Question 8

Photoautotroph

Answer 8

Organisms that can make their own energy using light and carbon dioxide via the process of photosynthesis

Question 9

Chemoautotroph

Answer 9

is an organism that produces its cellular energy, usually in the form of ATP, directly from the environment using a chemical source. It uses carbon dioxide

Question 10

Chemoheterotroph

Answer 10

are unable to utilize carbon dioxide to form their own organic compounds. Their carbon source is rather derived from sulfur, carbohydrates, lipids, and proteins.

Question 11

Photoheterotroph

Answer 11

an organism that makes energy from light but uses organic materials for its carbon source instead of inorganic carbon dioxide, which is used by photoautotrophs.

Question 12

Photosynthesis

Answer 12

Is the process of capturing energy from sunlight

Question 13

Oxygenic Photosynthesis

Answer 13

Energy from light drives the process of light energy transfers electrons from water/H2O (oxidize) to carbon dioxide/CO2 (reduced) to produce carbohydrates

Question 14

What are the similarities between photosynthesis and cellular respiration?

Answer 14

1. Redox reactions
2. Electron transport
3. Chemiosmosis

Question 15

Cyanobacteria

Answer 15

Cyanobacteria are the closest relatives of chloroplasts and do oxygenic photosynthesis

Question 16

What are the two pathways(stages) for photosynthesis?

Answer 16

1. Light-dependent reactions (occurs in the thylakoid membrane)
2. Light-independent reactions (aka Calvin cycle and occur in the stroma of the chloroplasts membrane)

Question 17

Light-dependent reactions

Answer 17

Are enzymes that only work in light and convert light energy into chemical energy (in ATP and the reduced electron carrier NADPH)

Question 18

Light-independent reactions

Answer 18

It uses the ATP and NADPH from the light-dependent reaction along with CO2 to produce carbohydrates

Question 19

Light

Answer 19

Is a form of electromagnetic radiation, which travels as a wave but also behaves as particles

Question 20

Photon

Answer 20

A light particle (that can excite an electron when a molecule absorbs it)

Question 21

Pigments

Answer 21

Molecules that absorb light within the visible spectrum

Question 22

Absorption Spectrum

Answer 22

Records the wavelengths over which a pigment absorbs light

Question 23

What are the two groups of pigments in photosynthetic organisms?

Answer 23

1. Chlorophyll A and B pigment

2. Carotenoid pigment

Question 24

Chlorophyll Pigment structure and purpose

Answer 24

Chlorophyll molecules have complex ring structures that absorbs light and drive the light reactions in photosynthesis

Question 25

Carotenoid Pigments

Answer 25

Are accessory pigments that absorbs wavelengths of light between the red and blue wavelengths, and transfer a portion of that energy to the chlorophylls

Question 26

Photosystem

Answer 26

large complexes of proteins and pigments (light-absorbing molecules) that are optimized to harvest light, play a key role in the light reactions.

Question 27

Photosystem 2

Answer 27

One of two light-capturing units in a chloroplast's thylakoid membrane; it has two molecules of 680nm chlorophyll A at its reaction center, makes ATP and uses electrons from light

Question 28

Photosystem 1

Answer 28

P700, makes NADPH and does not take place first

Question 29

What are the 2 photosystems?

Answer 29

1. Photosystem 1 (PSI) | 2. Photosystem 2 (PSII)

Question 30

Calvin cycle is composed of what?

Answer 30

It is composed of three distinct processes, each step is catalyzed by a specific enzyme

Question 31

What are the three processes of the Calvin cycle?

Answer 31

1. Carbon fixation 2. Reduction and sugar productions 3. Regeneration of RuBP

Question 32

Carbon Fixation

Answer 32

A CO2 molecule combines with a five-carbon acceptor molecule, ribulose-1,5-bisphosphate (RuBP). This results in 6C molecule that is unstable and breaks down into two 3C molecules

Question 33

2. Reduction and Sugar Production

Answer 33

is the second stage where ATP and NADPH are used to convert the 3-PGA molecules into molecules of a three-carbon sugar, glyceraldehyde-3-phosphate (G3P). This stage gets its name because NADPH donates electrons to, or reduces, a three-carbon intermediate to make G3P.

Question 34

Regeneration of RuBP

Answer 34

Some G3P molecules go to make glucose, while others must be recycled to regenerate the RuBP acceptor.

Question 35

RuBP Acceptor

Answer 35

Is a ribulose-1,5-bisphosphate

Question 36

Rubisco

Answer 36

Ribulose carboxylase, the enzyme that catalyzes the first step of the Calvin cycle (the addition of CO2 to RuBP, or ribulose bisphosphate).

Question 37

How many ATP can be made in the Calvin cycle?

Answer 37

54 ATP

Question 38

What can influence the efficiency and the way the Calvin cycle work?

Answer 38

Light intensity Temperature Water availability

Question 39

Photorespiration

Answer 39

is a wasteful pathway that occurs when the Calvin cycle enzyme rubisco acts on oxygen rather than carbon dioxide.

Question 40

C3 Plants

Answer 40

A "normal" plant—one that doesn't have photosynthetic adaptations to reduce photorespiration

Question 41

C4 Plants

Answer 41

A plant that physically separates the light-dependent reactions and the Calvin cycle

Question 42

Crassulacean Acid Metabolism (CAM)

Answer 42

A plant that uses a pathway to minimize photorespiration by separating the process of light-dependent reactions and the use of CO2 at different times

Question 43

Stomata

Answer 43

the small openings (pores) on the undersides of most leaves through which oxygen and carbon dioxide can move

Question 44

Chemosynthesis

Answer 44

Where some organisms use chemical energy rather than light energy to fix carbon

Question 45

Chlorophyll A

Answer 45

Is the primary pigment of photosynthesis and absorbs orange-red and blue-violet light

Question 46

Chlorophyll B

Answer 46

Is the accessory pigment of photosynthesis and is not necessary for photosynthesis to occur and absorbs blue light

Question 47

What is Chlorophyll A's main job?

Answer 47

Chlorophyll A's central role is to be a primary electron donor in the electron transport chain.

Question 48

What is Chlorophyll B's main job?

Answer 48

Chlorophyll B’s central role is to expand the absorption spectrum of organisms

Question 49

Cyclic Electron Transport

Answer 49

It uses only photosystem I and produces only ATP

Question 50

Antenna Complex in Photosynthesis

Answer 50

is a collection of pigments and proteins that capture and funnel energy from light.

Question 51

What is the role of Rubisco?

Answer 51

The role is to catalyze the bonding of CO2 to an unstable six-carbon compound. It also uses O2 and CO2 as substrates

Question 52

Carbon dioxide is “fixed” by bonding to what?

Answer 52

ribulose 1,5-bisphosphate, RuBP

Question 53

Chloroplast

Answer 53

Is n organelle with two membranes, the inner membrane being folded into stacks of thylakoids, forming the inner membrane space, the lumen, and the stroma