Question

Match the cell organelle/organism with the type of DNA present in them.

Organelle/organism	Type of DNA
Chloroplast	p. Double-stranded circular DNA
Mitochondria	q. cpDNA
E. coli	r. Single-stranded circular DNA

(a) A - p, B - q, C - r
(b) A - r, B - p, C - q
(c) A - q, B - r, C - p
(d) A - q, B - p, C - r

Answer 1

Hint: E. coli are prokaryotic cells that contain single 4.6 Mb chromosomes inside their cell. Mitochondria and chloroplasts are found in eukaryotic organisms and their chromosomal structure is also similar to that of eukaryotic cells.

Complete step by step answer:
Chloroplasts contain a special type of DNA known as Chloroplast DNA or cpDNA. They are 22 to 900 in number in each chloroplast. Mitochondrial DNA or mtDNA is double-stranded circular DNA. E. coli bacteria contain single-stranded circular DNA.
So, the correct answer will be ‘A - q, B - p, C - r’.

Additional Information: Let us know more about each type of DNA in detail.
The cpDNA is found in the chloroplasts and is a circular genome. Their number in each chloroplast ranges from 22 to 900 units and each of them encodes 123 genes. The cpDNA mostly gets transmitted maternally but in some cases biparental and in gymnosperms paternally.
Mitochondrial DNA or mtDNA is present inside the mitochondria and is double-stranded circular DNA. This DNA contains 37 genes, essential for the normal function of mitochondria. Approximately 100-1000 copies of this DNA is present inside each cell. The test of mtDNA shows the origin of maternal ancestors.
The gram-negative E. coli bacteria contain only one circular chromosome, hence said to have single-stranded circular DNA. The genome of this bacteria consists of a single 4.6 Mb circular chromosome.

Note: Chloroplasts and mitochondrial DNA are double-stranded while lower-class bacteria E. coli has single-stranded DNA. Special names such as cpDNA and mtDNA are provided to the DNA of chloroplasts and mitochondria. We can easily identify which cells the DNA belongs to by these names.