Question

Match the following processes with their location of occurrence in the cell: Process Location

A.	Proton moves into	I.	Mitochondria
B.	Respiration	II.	Thylakoid membrane
C.	$C_3$ cycle	III.	Thylakoid lumen
D.	$\mathrm{PS}I$ and $\mathrm{PS}\mathrm{II}$	IV.	Stroma

• A. A-III, B-I, C-IV, D-II
• B. A-II, B-I, C-III, D-IV
  
• C. A-IV, B-I, C-II, D-III
• D. A-III, B-IV, C-I, D-II

Answer 1

The correct option is A A-III, B-I, C-IV, D-II

Cellular respiration occurs in the mitochondria.

In case of photosynthesis, both the photosystems- $\mathrm{PS}I$ and $\mathrm{PS}\mathrm{II}$ are located in the thylakoid membrane.

Also, protons released from the splitting of water molecules and pumping of protons by cytochrome $b_{6}f$ from the stroma into the thylakoid lumen creates a pH difference/gradient between the thylakoid lumen and the stroma of the chloroplast. This pH gradient helps in the synthesis of $\mathrm{ATP}$ using the $\mathrm{ATP}$ synthase enzyme.

$C_3$ cycle takes place in the stroma of the chloroplasts.