Black (stem) rust of wheat is caused by:
1. Ustilago nuda
2. Puccinia graminis
3. Xanthomonas oryzae
4. Alternaria solani
Select the correct combination of the statements (a-d) regarding the characteristics of certain organisms:
(a) | Methanogens are archaebacteria that produce methane in marshy areas |
(b) | Nostoc is a filamentous blue-green alga that fixes atmospheric nitrogen |
(c) | Chemosynthetic autotrophic bacteria synthesize cellulose from glucose |
(d) | Mycoplasma lack a cell wall and can survive without oxygen |
The correct statements are:
1. | (a), (b) and (c) | 2. | (b), (c) and (d) |
3. | (a), (b) and (d) | 4. | (b) and (c) |
Given below is the diagram of a bacteriophage. In which one of the options, all the four parts A, B, C and D are correct?
A | B | C | D | |
1. | Sheath | Collar | Head | Tail fibres |
2. | Head | Sheath | Collar | Tail fibres |
3. | Collar | Tail fibres | Head | Sheath |
4. | Tail fibres | Head | Sheath | Collar |
In the five-kingdom classification, Chlamydomonas and Chlorella have been included in:
1. | Algae | 2. | Plantae |
3. | Monera | 4. | Protista |
Which one of the following sets of items in options 1 – 4 are correctly categorized with one exception in it?
ITEMS | CATEGORY | EXCEPTION | |
1. | Kangaroo, Koala, wombat | Australian marsupials | Wombat |
2. | Plasmodium, Cuscuta, Trypanosoma | Protozoan parasites | Cuscuta |
3. | Typhoid, Pneumonia, Diphtheria | Bacterial diseases | Diphtheria |
4. | UAA, UAG, UGA | Stop codons | UAG |
How many organisms in the list given below are autotrophs?
Lactobacillus, Nostoc, Chara, Nitrosomonas, Nitrobacter, Streptomyces, Sacharomyces, Trypanosoma, Porphyra, Wolfia
1. Five
2. Six
3. Three
4. Four
The causative agent of mad-cow disease is a:
1. bacterium
2. prion
3. worm
4. virus
Evolutionary history of an organism is known as:
1. Phylogeny
2. Ancestry
3. Palaeontology
4. Ontogeny