Photorespiration, C4, and CAM

Question 1

C3 Plants

The first organic product of carbon fixation is a

Answer 1

3-C compound.

Question 2

C3 Plants

During hot, dry days…

Answer 2

o Stomata is close
o Decline of CO2 level in the leaves
o O2 level builds up

Question 3

C3 Plants

During…
o Stomata is close
o Decline of CO2 level in the leaves
o O2 level builds up

Answer 3

hot, dry days

Question 4

why is stomata closed?

Answer 4

to prevent water loss

Question 5

C3 Plants

rubp binds with

Answer 5

O2

Question 6

C3 Plants

Low temperature
___ CO2:O2 ratio

Answer 6

High

Question 7

C3 Plants

High temperature
___ CO2:O2 ratio

Answer 7

Low

Question 8

RuBisCO is not loyal to CO2

Answer 8

evolutionary baggage

Question 9

once O2 binds with RUBP, it produces _____

Answer 9

2-phosphoglycolate

Question 10

o Toxic to plants
o Inhibits distinct reactions in the Calvin Cycle.

Answer 10

2-phosphoglycolate

Question 11

o Decreases the photosynthetic output
o Uses ATP rather than generating it
o No sugar produced
o CO2 is lost rather than having it
fixed (50%)

Answer 11

Photorespiration

Question 12

pros of photorespiration

Answer 12

o photoprotective effects (preventing light-induced damage to the molecules involved in photosynthesis)
o help maintain redox balance in cells
o support plant immune defenses

Question 13

the first stable molecule formed from the fixation of CO2 is a 4-carbon organic acid.

Answer 13

C4 photosynthesis

Question 14

common in habitats that are hot, but are less abundant in areas that are cooler.

Answer 14

C4 plants

Question 15

C4 Photosynthesis

first stable molecule formed from the fixation of CO2 is a

Answer 15

4-carbon organic acid

Question 16

C4 Plants

Begins in _____ (light-dependent reaction) and is completed in _____ (Calvin Cycle).

Answer 16

mesophyll cells and bundle-sheath cells

Question 17

is a special structure in the leaves of C4 plants where the tissue equivalent to spongy mesophyll cells is clustered in a ring around the leaf veins outside the bundle sheath cells.

Answer 17

Kranz anatomy

Question 18

Kranz anatomy

Answer 18

is a special structure in the leaves of C4 plants where the tissue equivalent to spongy mesophyll cells is clustered in a ring around the leaf veins outside the bundle sheath cells.

Question 19

The C4 Pathway

Answer 19

• In mesophyll cells, the enzyme PEP carboxylase adds CO₂ to PEP, forming a four- carbon compound.
• The four-carbon compound (such as malate) moves into a bundle-sheath cell via plasmodesmata.
• In bundle-sheath cells, an enzyme releases CO₂, which enters the Calvin cycle.

Question 20

it can fix CO2 even when CO2 concentrations are low

Answer 20

PEP carboxylase

Question 21

C4 plants expend -___ more ATP
to synthesize 1 molecule of
glucose.

Answer 21

12

Question 22

The goal is to increase the concentration of CO2

Answer 22

C4 Photosynthesis

Question 23

CAM

Answer 23

Crassulacean Acid Metabolism

Question 24

• first observed in Crassulaceae plants
• adaptation to the arid environment
• almost similar to C4

Answer 24

CAM

Question 25

C4 Plants

during the day, stomata is ___ and

Answer 25

close, release CO2 and conserves water

Question 26

C4 Plants

at night, stomata is ___ and

Answer 26

open, take CO2

Question 27

tropical grasses like corn, sugarcane

Answer 27

C4 plants

Question 28

A type of plant that produce a 4-carbon compound, oxaloacetate
as the first stable product of carbon fixation process

Answer 28

C4 plants

Question 29

Mesophytic

Answer 29

C4 plants

Question 30

12 NADPH and 18 ATP are needed for the production of glucose

Answer 30

C4 plants

Question 31

Mesophyll cells and bundle sheath cells

Answer 31

C4 plants

Question 32

Fix carbon in Cytoplasm, - attach CO2 to PEP

Answer 32

C4 plants

Question 33

More energy efficient

Answer 33

C4 plants

Question 34

Succulents, pineapple, agave

Answer 34

CAM plants

Question 35

A type of plant that utilize CAM photosynthesis

Answer 35

CAM plants

Question 36

Xerophytic

Answer 36

CAM plants

Question 37

12 NADPH and 39 ATP are needed for the production of glucose

Answer 37

CAM plants

Question 38

Only in mesophyll cells

Answer 38

CAM plants

Question 39

Fix carbon at night only, fix it to organic molecules

Answer 39

CAM plants

Question 40

Best water conservation

Answer 40

CAM plants