Photochemical smog pollution does not contain:

1. ozone

2. nitrogen dioxide

3. carbon dioxide

4. PAN (Peroxy Acyl Nitrate)

Moss peat is used as a packing material for sending flowers and live plants to distant places because:

1. it is easily available

2. it is hygroscopic

3. it reduces transpiration

4. it serves as a disinfectant

A common structural feature of vessel elements and sieve tube elements is:

1. thick secondary walls

2. pores on lateral walls

3. presence of P-protein

4. enucleate condition

The thalloid body of a slime mould (Myxomycetes) is known as:
1. protonema
2. Plasmodium
3. fruiting body
4. mycelium

In which mode of inheritance do you expect more maternal influence among the offspring?

1. Autosomal

2. Cytoplasmic

3. Y-linked 

4. X-linked

What type of placentation is seen in sweet pea?

1. Basal

2. Axile

3. Free-central

4. Marginal

Long filamentous threads protruding at the end of a young cob of maize are:

Conifers differ from grasses in the:

1. production of seeds from ovules

2. lack of xylem tracheids

3. absence of pollen tubes

4. formation of endosperm before fertilization

How many different kinds of gametes will be produced by a plant having the genotype AABbCC?

1. Three

2. Four

3. Nine

4. Two

In maize, hybrid vigour is exploited by:

1. bombarding the protoplast with DNA

2. crossing of two inbred parental lines

3. harvesting seeds from the most productive plants

4. inducing mutations