Which of the following statements is wrong for viroids?
1. Their RNA is of high molecular weight
2. They lack a protein coat
3. They are smaller than viruses
4. They cause infections
Methanogens belong to
1. Slime moulds
2. Eubacteria
3. Archaebacteria
4. Dinoflagellates
Select the wrong statement.
1. | Diatoms are microscopic and float passively in water. |
2. | The walls of diatoms are easily destructible. |
3. | ‘Diatomaceous earth’ is formed by the cell walls of diatoms. |
4. | Diatoms are chief producers in the oceans. |
Select the mismatch.
1. Methanogens-Prokaryotes
2. Gas vacuoles-Green bacteria
3. Large central vacuoles-Animal cells
4. Protists-Eukaryotes
Which of the following rRNAs acts as structural RNA as well as ribozyme in bacterial?
1. 5-8s rRNA
2. 5S rRNA
3. 18 S rRNA
4. 23S rRNA
Study the four statements (A – D) given below and select the two correct ones out of them:
A. Definition of biological species was given by Ernst Mayr.
B. Photoperiod does not affect reproduction in plants.
C. Binomial nomenclature system was given by R. H. Whittaker.
D. In unicellular organisms, reproduction is synonymous with growth.
The two correct statements are
1. A and B
2. B and C
3. C and D
4. A and D
Which among the following are the smallest living cells known without a definite cell wall that are pathogenic to plants as well as animals and can survive without oxygen?
1. Bacillus
2. Pseudomonas
3. Mycoplasma
4. Nostoc
Which of the following are found in extreme saline conditions?
1. Archaebacteria
2. Eubacteria
3. Cyanobacteria
4. Mycobacteria
Viroids differ from viruses in having
1. DNA molecules with protein coat
2. DNA molecules without protein coat
3. RNA molecules with protein coat
4. RNA molecules without protein coat
Which of the following features is common to prokaryotes and many eukaryotes?
1. Chromosomes present
2. Cell wall present
3. Nuclear membrane present
4. Sub cellular organelles present