Science
Which of the following pairs of cell organelles contains DNA?
(i) Chloroplasts, Ribosomes
(ii) Mitochondria, Nucleus
(iii) Golgi bodies, Ribosomes
(iv) Nucleus, Lysosomes
Answer
The correct pair is (ii) Mitochondria, Nucleus.
The nucleus contains chromosomes made of DNA, and mitochondria also have their own DNA. Ribosomes, Golgi bodies and lysosomes do not contain DNA, which is why the other options are incorrect. (Although chloroplasts also contain DNA, ribosomes in option (i) do not, so that pair is not fully correct.)
Related Questions
Two students, Renu and Rohit, were having a discussion on the plastids. Renu emphasised that all parts of the plants, even roots, contain plastids. However, Rohit did not agree with the statement and told her that plastids are absent in plant roots since the roots are underground and do not need to perform photosynthesis. Who is correct? Justify your answer.
Mitochondria and chloroplasts are two important organelles in a plant cell. Discuss how these two organelles are structurally and functionally similar to each other, and different from each other.
A researcher carried out an experiment in which she took two carrots of similar size. She placed one carrot in plain water and the other carrot in concentrated salt solution (Fig. 2.21). After 24 hours she recorded her observations.

(i) What hypothesis does she want to test through this experiment?
(ii) What would you suggest for the improvement of this experiment?
(iii) Why does the carrot in plain water stay stiff and crunchy, but the carrot in concentrated salt solution become rubbery and limp?
Indicate the presence or absence of following structures in bacterial and animal cells:
Structures in a cell Bacterial cell Animal cell Chromosome Nucleus Mitochondria Golgi complex Chromoplasts