Which one of the following growth regulators is known as stress hormone?
abscsic acid
Ethylene
GA3
GA3
A.
abscsic acid
Abscisic Acid (ABA) is also known as stress hormone or dormin because it is produced in much higher amounts, when plants are subjected to various kinds of stresses. It often gives plants organs a signal that they are undergoing physiological stresses such as lack of water, saline soil, cold temperature and frost. ABA often cause responses that help plants and protect against these stresses.
An aggregate fruit is one which develops from
multi carpellary syncarpous gynoecium
Multi carpellary apocarpus gynoecium
complete inflorescence
complete inflorescence
Which one of the following living organisms completely lacks a cell wall?
Cyanobacteria
Sea-fan (Gorgonia)
Saccharomyces
Saccharomyces
An alga which can be employed as food for human being is
Ulothrix
Chlorella
Spirogyra
Spirogyra
Viruses have
DNA enclosed in a protein coat
prokaryotic nucleus
single chromosome
single chromosome
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
Anoxygenic photosynthesis is characteristic of
rhodospirlllum
Spirogyra
Chlamydomonas
Chlamydomonas
Select the taxon mentioned that represents both marine and freshwater species
Echinoderms
Ctenophora
Cephalochordata
Cephalochordata