Anoxygenic photosynthesis is characteristic of 

• rhodospirlllum

• Spirogyra

• Chlamydomonas

• Chlamydomonas

A few normal seedlings of tomato were kept in a dark room. After a few days they were found to have become white - coloured like albinos. Which of the following terms will you use to describe them?

• Mutated

• Embolised

• Etiolated

• Etiolated

Which one of the following growth regulators is known as stress hormone?

• abscsic acid

• Ethylene

• GA₃

• GA₃

Male gametophyte with least number of cell is present in

• Pteris

• Funaria

• Lillium

• Lillium

An aggregate fruit is one which develops from

• multi carpellary syncarpous gynoecium

• Multi carpellary apocarpus gynoecium

• complete inflorescence

• complete inflorescence

Viruses have

• DNA enclosed in a protein coat

• prokaryotic nucleus

• single chromosome

• single chromosome

The first human hormone produced by recombinant 

• insulin

• estrogen

• thyroxin

• thyroxin

An alga which can be employed as food for human being is 

• Ulothrix

• Chlorella

• Spirogyra

• Spirogyra

Select the taxon mentioned that represents both marine and freshwater species

• Echinoderms

• Ctenophora

• Cephalochordata

• Cephalochordata

20.

Which one of the following living organisms completely lacks a cell wall?

• Cyanobacteria

• Sea-fan (Gorgonia)

• Saccharomyces

• Saccharomyces