Unit 2 - Lecture 3

Question 1

Explain what phototrophy means

what is photosynthesis?

Answer 1

• uses light energy as energy source
• used for photosynthesis, converting light energy to chemical energy
• organisms capable of photosynthesis are called phototrophs

Question 2

what are autotrophs?

Answer 2

• fix CO2 and us it as a carbon source
• ex. photoautotrophy = energy acquired from light is used to recuded CO2 to organic compounds
• if carbon source is organic, the photsynthetic organism is called photoheterotroph

Question 3

what is the photosynthetic pigment used in photosynthesis?

2 different ones

Answer 3

1. cholorphylls
   - plants
   - algae
   - cyanobacteria
2. bacteriocholorphylls
   - purple bacteira
   - green bacteria

these absorb light (photon) to create ATP (chemical energy)

Question 4

what is the two rxns in photosynthesis?

what is the donor?

Answer 4

• ATP and NADH produced to reduce CO2 and create organic compounds (sugar)
• algae, plants, cyanobacteria - H2O
• green and purple sulfur bacteria - H2S