Science
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 |
Answer
| Structures in a cell | Bacterial cell | Animal cell |
|---|---|---|
| Chromosome | Present (single, circular DNA) | Present |
| Nucleus | Absent (has a nucleoid instead) | Present |
| Mitochondria | Absent | Present |
| Golgi complex | Absent | Present |
| Chromoplasts | Absent | Absent |
Bacterial cells are prokaryotic, so they lack a well-defined nucleus and membrane-bound organelles such as mitochondria and the Golgi complex. Their genetic material is present as a single circular DNA molecule in a region called the nucleoid. Chromoplasts are plastids found only in plant cells, so they are absent in both bacterial and animal cells.
Related Questions
Which of the following pairs of cell organelles contains DNA?
(i) Chloroplasts, Ribosomes
(ii) Mitochondria, Nucleus
(iii) Golgi bodies, Ribosomes
(iv) Nucleus, Lysosomes
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?
Carry out the following experiment:
Take four peeled potato halves and scoop each one out to make potato cups. One of these potato cups should be made from a boiled potato. Place each of the potato cups in a beaker containing water (Fig. 2.22). Now, set up the experiment as follows:
(a) Keep Cup A empty.
(b) Add one teaspoon sugar in Cup B.
(c) Add one teaspoon salt in Cup C.
(d) Add one teaspoon sugar in the boiled potato in Cup D.
Observe the four potato cups for at least two hours and answer the following questions:
(i) Explain why water gathers in the hollowed portion of Cup B and Cup C.
(ii) Why is Cup A necessary for this experiment?
(iii) Explain why water does not gather in the hollowed portions of Cups A and D.
Identify the pair that incorrectly matches the cell organelle with its function.
(i) Ribosome — Protein synthesis
(ii) SER — Lipid and cellulose synthesis
(iii) Lysosome — Digestion of foreign agents