Which of these correctly explains one difference between the processes of photosynthesis and respiration? a) the krebs cycle occurs only in the chloroplast. b) glycolysis takes place only in the mitochondria. c) the calvin cycle takes place only in the chloroplast. d) the electron transport chain happens only in the mitochondria.

C

Explanation:

The photosynthetic and respiratory process are anabolic and metabolic processes that occur in the cells of living organisms respectively. Photosynthesis is a process unique to autotrophs alone i.e. organism that have the ability to make their own food using trapped energy from sunlight. Thus, all autotophs including plants, algae etc must contain photosynthetic pigments called CHLOROPHYLL, which is embedded in their CHLOROPLAST. The first stage of photosynthesis which is light dependent occurs in the thylakoid membrane of the CHLOROPLAST while the second stage called CALVIN CYCLE occurs in the matrix of the CHLOROPLAST called STROMA.

On the other hand, all living organisms undergo cellular respiration to release usable form of energy (ATP). Glycolysis, the first step in cellular respiration, is common to all organisms because it does not require oxygen. The aerobic respiration (need oxygen) further involves the Kreb's cycle and Oxidative phosphorylation (Electron transport chain). These two processes occur in the inner membrane of the mitochondria called CRISTAE in eukaryotes, whereas, for prokaryotes that lack mitochondria, they still undergo the electron transport chain (ETC) but it occurs across their cell membrane instead.

In a nutshell, (Calvin cycle) photosynthesis cannot occur in any other place/organnelle other than the Chloroplast.