Which of the following is correct about viroids?

1. They have free RNA without protein coat.

2. They have DNA with protein coat.

3. They have free DNA without protein coat.

4. They have RNA with protein coat.

Which of the following is incorrect about Cyanobacteria?

1. They are photoautotrophs

2. They lack heterocysts

3. They often form blooms in polluted water bodies

4. They have chlorophyll similar to green plants

Match the organisms in Column I with habitats in Column II.

Select the correct answer from the options given below:

Which of the following statements is correct?

1. Lichens do not grow in polluted areas.

2. Algal component of lichens is called mycobiont.

3. Fungal component of lichens is called phycobiont.

4. Lichens are not good pollution indicators.

Mad cow disease in cattle is caused by an organism which has:

1. Inert crystalline

2. Abnormally folded protein

3. Free RNA without protein coat

4. Free DNA without protein coat

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 

Which one of the following sets of items in options 1 – 4 are correctly categorized with one exception in it?

In the five-kingdom classification, Chlamydomonas and Chlorella have been included in:

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?

Black (stem) rust of wheat is caused by:
1. Ustilago nuda
2. Puccinia graminis
3. Xanthomonas oryzae
4. Alternaria solani