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

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.

Animals differ from plants in

1. Being multicellular

2. Having cell wall

3. Being heterotrophic

4. Being eukaryotic

Choose the correct features regarding the most common asexual spores of sac fungi.

a. Haploid

b. Exogenous

c. Thick walled

d. Produced during unfavorable conditions

e. Grow in basipetal manner

1. a, c and d

2. a, b and c

3. b, c, d and e

4. All except c and d

Red tides are due to the rapid multiplication of

1. Cyanobacteria

2. Chlamydomonas

3. Gonyaulax

4. Diatoms

Which of the following is not true for amoeboid protozoan?

1. Pseudopodia helps in feeding

2. Silica shells present in marine form

3. Contractile vacuole

4. Flagella helps in locomotion

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.

Members of myxomycetes (slime moulds) move from one place to other by:

(1) Ciliary movements

(2) Cyclosis

(3) Amoeboid movement

(4) Rotation