Question

Could someone please help me answer these 5 biology questions related to photosynthesis.

1. If NADP+ is not available as the final electron acceptor, where will the electron go?

Select one:

a. The electron is ejected into the stroma.

b. The electron is returned back to the photosystem through a series of proteins.

c. The electron is donated to H2O.

d. The electron is recycled directly back to the reaction center pigment.

2. Which of the following is NOT true regarding the light-dependent reactions?

Select one:

a. There are other light absorbing pigments than chlorophyll

b. Oxygen atoms in these reactions originate from water

c. Chlorophyll is great at absorbing green light

d. Photons excite electrons that are passed between photosystems

3. What is the complete balanced equation for photosynthesis?

Select one:

a. light energy + 6CO2 + 6H20 -> C6H12O6 + 6O2

b. C6H12O6 + 6O2 + 6H2O -> 12H20 + 6CO2 + energy

c. 2 light energy + 6CO2 + 6H20 -> C6H12O6 + 6H2O + 3 O2

d. 6C6H12O6 + 6O2 -> 6H2o + 6CO2 + energy

4. Which of the following is NOT true about ATP Synthase in chloroplasts?

Select one:

a. directly absorbs photon energy

b. helps to synthesize ATP

c. sits in the thylakoid membrane

d. uses protons moving from the thylakoid lumen to the stroma

5. The light-dependent reactions take place in the _________ and the light-independent reactions (Calvin Cycle reactions) occur in the __________.

Select one:

a. Stomata, thylakoid membrane

b. Vacuole, stroma

c. Thylakoid membrane, stroma

d. Stroma, thylakoid membrane

Thanks so much!!!!

Answer 1

1) electrons moving through the electron transport chain finally reaches NADPH, the NADP+ reductase transfers the electron and H+ to the NADP+ to make NADPH, if NADP+ is not available the electrons will be released to the stroma, it can be transferred to water which is already in the reduced state, it cannot be transferred back to the proteins so the answer is a) The electron is ejected into the stroma.

2) light-dependent reactions involves the photosystems and other complexes in the thylakoid membrane, electrons from the PSII is excited and it moves through the electron transport chain , during the electron transport the energy of the electrons is used to pump H+ from the stroma to the thylakoid, the electrons lost from the PSII is replaced with electrons from the water, water is split to oxygen, electrons and H+, chlorophyll is a green coloured pigment, it reflects the green colour it does not absorb green colour so the answer is c) Chlorophyll is great at absorbing green light.

3) using light energy carbon dioxide is fixed to glucose, the balanced equation is

light energy + 6CO2 + 6H20 C6H12O6 + 6O2

6 molecules of Carbon dioxide is converted to glucose.

answer is a)  light energy + 6CO2 + 6H20 C6H12O6 + 6O2

4) ATP synthase is located in the thylakoid membrane, it synthesizes ATP using the energy of the H+ gradient across the thylakoid membrane. it does not absorb energy from photons.

so the answer is a. directly absorbs photon energy

5) light reaction occurs in the thylakoid membrane, the complexes for the light reaction is located on the thylakoid membrane, the dark reactions occur in the stroma, the enzymes required for the dark reactions are located in the stroma.

so the answer is c. Thylakoid membrane, stroma