Chapter 11 - Photosynthesis

Question 1

(LDR) What is produced in the light dependent stage of photosynthesis?

Answer 1

• Reduced NADPH
• ATP
• 1/2 Oxygen molecule
• 2 Hydrogens

Question 2

(LDR) Where does the energy come from in the light dependent reaction?

Answer 2

From light absorbed in the chloroplasts from the sun

Question 3

(LDR) How do the electrons move throughout the chain?

Answer 3

• Redox reactions through electron carriers

Question 4

(LDR) Where do the electrons in the light dependent chain come from?

Answer 4

Photolysis of water in the thylakoid space, electrons move into the chloroplast

Question 5

(LDR) What does the photolysis of water produce?

Answer 5

Produces :
- 2 hydrogen ions
- 2 electrons
- 1/2 oxygen molecules

Question 6

(LDR) What happens when the electrons reach the hydrogen pump?

Answer 6

Allows hydrogen ions to move through the hydrogen pump, from the stroma (low concentration of hydrogen ions) to the thylakoid space (high concentration of hydrogen ions)

Question 7

(LDR) What are the chloroplasts also known as?

Answer 7

Photosystem 2 / chloroplast 2
Photosystem 1 / chloroplast 1

Question 8

(LDR) What happens at the second chloroplast?

Answer 8

The electrons gain more energy to allow them to move up the chloroplast and continue across the bilayer

Question 9

(LDR) What is NADP+?

Answer 9

It is a coenzyme (something that helps an enzyme work

Question 10

(LDR) What happens to the electrons at the end of the light dependent chain?

Answer 10

They join onto NADP+ with hydrogen ions from the ATP SYNTHASE to create reduced NADPH

Question 11

(LDR) What happens to the hydrogen ions from the hydrogen pump and photolysis of water?

Answer 11

They are moved through ATP SYNTHASE, causing ADP and Pi to join together creating ATP

Question 12

(LDR) What theory is the creation of ATP through ATP SYNTHASE?

Answer 12

Chemiosmotic theory

Question 13

(LDR) What are the ATP and reduced NADPH used for?

Answer 13

The light independent reaction

Question 14

(LDR) Where does the light dependent reaction happen?

Answer 14

In the thylakoid membrane of a thylakoid

Question 15

What are the adaptions of the chloroplast for the light dependent reaction?

Answer 15

• Thylakoid membrane have a large SA due to flattened shape
• General membrane contains ATP synthase
• Arrangement of proteins in grana hold chlorophyll in precise way to maximise absorbtion of light
• Contain DNA and ribosomes to produce proteins required

Question 16

What is the NADP+ also known as?

Answer 16

The final electron acceptor