NEET BIOLOGY

Detailed explanation-1: -Mitochondria and chloroplasts are semi-autonomous cell organelles, which contain their own DNA and protein synthesising machinery. They arise from pre-existing organelles and their functions are partially controlled by the nucleus of cell as well as the organelles themselves.

Detailed explanation-2: -Plant chloroplasts are large organelles (5 to 10 m long) that, like mitochondria, are bounded by a double membrane called the chloroplast envelope (Figure 10.13). In addition to the inner and outer membranes of the envelope, chloroplasts have a third internal membrane system, called the thylakoid membrane.

Detailed explanation-3: -Mitochondria and chloroplast are semi-autonomous cell organelles, which contain their own DNA and protein synthesizing machinery. They arise from pre-existing organelles and their functions are partially controlled by nucleus of cell and partially themselves.

Detailed explanation-4: -This is due to their evolutionary origin as primitive prokaryotes. They eventually became a part of the eukaryotic cell. They can replicate independently and produce their own proteins.

Detailed explanation-5: -Mitochondria and chloroplasts are called semi-autonomous organelles because they have their own DNA, mRNA, tRNA, ribosomes and they replicate by binary fission so they are said to be self governing. Semi-autonomous means they are in a symbiotic relationship with the cell and have evolved to become part of it.