9 Energy Autotrophs

Question 1

Trophy

Answer 1

Related to food

Question 2

Autotrophy

Answer 2

Obtains energy from inorganic source
-photosynthesis (light)
-chemosynthesis (oxidation)

Question 3

Heterotrophy

Answer 3

Uses organic C synthesized brothers for energy

Question 4

PAR

Answer 4

Photosynthetically Active Radiation (visible light)
- variable depending on clouds, landscape features, position of a plant, aquatic system, etc

Question 5

Where is red/blue light absorbed in water?

Answer 5

Red- high up by green organisms
Blue- deep down by red organisms

Question 6

How deep can water penetrate in water?

Answer 6

100-200 m

Question 7

What are the variables in a photosynthetic response curve?

Answer 7

Lsat- irradiance saturation
Pmax- max net photosynthesis
LCP- light compensation point (point where more sugar is produced than what is used)
Photosynthetic photon fluxes density- number of PAR photons passing through an area per time
Net photosynthetic rate- total photosynthesis- respiration

Question 8

How do photosynthetic response curves vary among individuals in a species?

Answer 8

• seedlings grown in open conditions (high Pmax and Lsat

-seedlings grown in shade (low Pmax and Lsat), can be damaged by direct sunlight, more efficient using low PPFD

Photosynthetic photon flux density

Question 9

How do photosynthetic response curves vary among individuals in a species?

Answer 9

• seedlings grown in open conditions (high Pmax and Lsat

-seedlings grown in shade (low Pmax and Lsat), can be damaged by direct sunlight, more efficient using low PPFD

Photosynthetic photon flux density

Question 10

How do photosynthetic response curves vary among individuals in a species?

Answer 10

• seedlings grown in open conditions (high Pmax and Lsat

-seedlings grown in shade (low Pmax and Lsat), can be damaged by direct sunlight, more efficient using low PPFD

Photosynthetic photon flux density

Question 11

C3 photosynthesis

Answer 11

No anatomic/time separation of processes

-initial C fixation: mesophyll (day)
-Calvin cycle: mesophyll (day)

Question 12

C4 photosynthesis

Answer 12

Anatomic separation of processes

-initial C fixation: mesophyll (day)
-Calvin cycle: bundle sheath cells (day)

Question 13

CAM photosynthesis

Answer 13

Time separation of processes

-initial C fixation: mesophyll (night)
-Calvin cycle: mesophyll (day)

Question 14

What are the problems in photosynthesis with hot climates

Answer 14

-RUBISCO is inefficient in high temps (Calvin cycle)

-open stomata wastes water
-closed stomata: O² increases, photosynthesis suppressed

Question 15

How do plants deal with hot climates?

Answer 15

1. C4
   Separates processes anatomically: O2 accumulates in mesophyll
   Calvin cycle in bundle cells (stomata stay closed)
   Water efficient
2. CAM
   Separates timing of processes: night- open stomata and fix
   C -> C⁴: daytime- close stomata and complete c-fixation

Question 16

What are the main differences in efficiency between C³ and C⁴?

Answer 16

C⁴: more water efficient, but this is not a limiting factor in rainforests for example

C³: More energy efficient than C4

Question 17

CAM stands for? How does it work?

Answer 17

Crassulacean Acid Metabolism

2 steps at different times
Light reaction + Calvin cycles (finish carbon fixation ton C⁴) during the day
Open stomata (CO² in, O² out) + calvin cycle (start) at night

Question 18

Howdid C4 and CAM evolve?

Answer 18

Covergently

Question 19

Where do different photosynthesis methods occur?

Answer 19

Cool, wet conditons: C3

Warm, dry conditions (carbon fixation at night): CAM
Warm, dry conditions (carbon fixation at nig