Q4. Assertion: the dark reactions are light-dependent. Reason: they use the ATP and NADPH formed in the light reactions. Are both true, and does the reason explain the assertion?
Both are true, and the reason explains the assertion (NCERT page 136).
Q5. In which part of the chloroplast do enzymatic reactions synthesise sugar, and what does the sugar form?
In the stroma; the sugar in turn forms starch (NCERT page 136).
Q6. Why do chloroplasts align along the walls of mesophyll cells?
So that they get the optimum quantity of the incident light (NCERT page 136).