Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Botany > Photosynthesis: Calvin-Benson Cycle > Flashcards

Photosynthesis: Calvin-Benson Cycle Flashcards

my strong, independent reaction

1
Q

Predominant pathway of autotrophic CO2 fixation

A

calvin-benson cycle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Number of steps/biochemical reactions in the Calvin-Benson Cycle

A

thirteen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Three major steps in Calvin-Benson Cycle

A
  1. carboxylation of RuBP → 2 molecules of 3-PGA
  2. reduction of 3-PGA → G3P
  3. regeneration of RuBP from G3P

or each co2 molecule that reacts with one RuBP, two molecules of 3-PGA f

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

An enzyme that catalyzes carboxylation and oxygenation of RuBP.

A

RubiSCO

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Plants that form 3-PGA as the 1st stable compound.

A

C3 plants

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Types of RubiSCO

A

I, II, III, IV

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q
  • Type/s of RubiSCO having catalytic function.
  • Type/s of RubiSCO with lost RubisCO activity.
  • Type of RubiSCO that harbors small subunits, consisting of eight large and eight small subunits; found in most autotrophic organisms; most abundant protein
A

types I, II, III
type IV
type I

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Reduction is a two-step reaction that converts the 6 molecules of ___ from the carboxylation stage into 6 molecules of ___.

A

3‐PGA to G3P

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is regenerated in the “regeneration” phase of Calvin-Benson Cycle?

A

RuBP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What modulates the levels of stromal enzymes encoded in nuclear and chloroplast genomes?

A

light

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Light‐linked ___ regulates the Calvin–Benson Cycle.

A

posttranslational modifications of enzymes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q
  • Accumulation of stromal enzymes = ↓ catalytic effect
  • Posttranslational modifications of enzymes = rapid catalytic effect
A

true

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Two mechanisms that alter the protein structure of enzymes for their catalytic rates.

A
  1. rubiSCO activase
  2. ferredoxin–thioredoxin system (FTS)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

An ATP-dependent enzyme that modulates RubiSCO activity.

A

rubiSCO activase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Rubisco activity has a fast capacity for CO2 fixation.

A

false; 1–12 CO2 fixations per second

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

RubiSCO is an “automatic” catalyst. True or False?

A

false; it must first be activated.

17
Q

An inhibitor, together with other sugar phosphates, that is removed by RubiSCO activase to kickstart RubiSCO catalytic activity.

A

CAP1

18
Q

A mechanism that regulates enzymes by redox transitions.

A

ferredoxin–thioredoxin system

19
Q

Ferredoxin–thioredoxin system uses ___ to regulate Fructose 1,6-bisphosphatase, etc.

A

ferredoxin

20
Q

The oxygenase activity of rubisco causes partial loss of the carbon fixed by the Calvin–Benson cycle and yields ____, an inhibitor of two chloroplast enzymes: triose phosphate isomerase & phosphofructokinase.

A

2-phosphoglycolate

21
Q

2-phosphoglycolate is metabolized through the process of ___.

A

photorespiration

22
Q

Where does photorespiration occur?

A

mitochondria, peroxisome, chloroplast

23
Q

Why do C3 plants close their stomata during dry and hot climate?

A

open stomata lead to water loss and dehydration; however, it also increases oxygen production and inhibits gas exchange.

24
Q

When the concentration of O2 is relatively high compared to the CO2
concentration, photorespiration becomes a serious problem.

A

true

25
Q

Photorespiration is also known as ___.

A

C2 pathway

26
Q

How many molecule/s of O2 is needed to produce 1 molecule of CO2?

A

two

27
Q

For every 2 molecules of glycine that enters the mitochondrion, 1 molecule each of serine, CO2, and ammonia are produced, and 1NAD+ is reduced to NADH. True or False?

A

true

28
Q

C2 pathway interacts with:
1. Nitrogen metabolism at multiple levels
2. Cell redox homeostasis
3. C1 metabolism
4. Expression of transcription factors

A

true

29
Q

Two types of carbon-concentrating mechanisms that land plants use for
increasing the concentration of CO2
at the RubiSCO carboxylation site.

A

C4 pathway
Crassulacean Acid Metabolism

30
Q

C4 cycle separates ____; while
CAM separates ____.

A

spatially
temporally

31
Q

C3 plants produce ____; while
CAM plants produce ____.

A

3-PGA
OAA (oxaloacetic acid)

32
Q

Two concentric cylinders of cells in C4 plants’ leaves.

A

mesophyll cells: outer cylinder
bundle-sheath cells: inner cylinder

33
Q

Anatomy unique to plants that use C4 pathway which provides spatial separation of carbon fixations in two types of cells and photosynthetic reactions.

A

kranz anatomy

34
Q

C4 pathway requires more energy. True or False?

A

true; C3 pathway consumes 3 ATP : 2
NADPH : 1 CO2 vs. C4 pathway, 5 ATP : 2 NADPH : 1 CO2

35
Q

CAM also utilizes PEP carboxylase. True or False?

A

true

36
Q

Difference of CAM with C4 pathway:
▪ Stomata are closed during the day, open during night.
▪ Carry out light reaction & CO2
fixation at different TIME of the day ~ temporal separation.

A

true

Botany (9 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions