lecture 7

Question 1

photosynthesis

Answer 1

• converts light energy to chemical energy for food
• creates almost all organic olecules that power life
• creates almost all O2 used for cellular respiration

Question 2

light reactions

Answer 2

• convert solar energy to chemical energy of ATP and NADPH

Question 3

calvin cycle

Answer 3

• uses ATP and NADPH to convert CO2 to sugar

Question 4

photosynthesis

Answer 4

autotrophs
- self sustainable without eating anything derived from other organisms
- producers of biosphere

phototrophs
- use energy of sun to produce organic molecules from water and CO2

Question 5

autotrophs

Answer 5

phototrophs
- light and CO2
- prokaryotes (cyanobacteria); plants (algae)

chemotrophs
- inorganic chemicals and CO2
- prokaryotes (sulfolobus)

Question 6

heterotrophs

Answer 6

photoheterotroph
- light and organic compounds
- prokaryotes (chloroflexus)

chemoheterotroph
- organic compounds
- prokaryotes (clostridium); protists; fungi; animals; plants

Question 7

photosynthesis conversions (plants)

Answer 7

• plants: occurs in chloroplast
• green leaves from chlorophyll pigment
• light absorbed by chlorophyll
• chloroplasts contained in mesophyll cells
• stomata are valves allowing CO2 in and O2 out

Question 8

key characteristics of chlorplast

Answer 8

• chlorophyll: located in membrane of thylakoid
• outer membrane
• intermembrane space
• inner membrane
• stroma (spaces)
• granum (whole thylakoid)
• thylakoid (section of granum)
• thylakoid space (space in thylakoid)

Question 9

how do CO2 and H2O combine to make carbohydrate and oxygen

Answer 9

• 6 CO2 + 12 H2O + light –> sugar + 6 H2O + 6 O2

Question 10

tracking atoms

Answer 10

• light rxns split water
• electrons go to sugar
• oxygen released

Question 11

2 stages of photosynthesis

Answer 11

light rxns
- split water
- release oxygen
- reduce NADP+ to NADPH
- generate ATP from ADP (photphosorylation)

calvin cycle
- forms sugar from CO2 using ATP and NADPH