Root development is promoted by
abscisic acid
auxin
gibberellin
gibberellin
B.
auxin
The higher concentration of auxin causes inhibition of root elongation, but the number of lateral branches in the root is considerably increased. In plant tissue cultures, relatively amounts of auxin and cytokinin induce the development of root, shoot or undifferentiated mass of tissues. High auxin to cytokinin ratio favours the root development high cytokinin to auxin ratio favours shoot development, while intermediate concentration results in the formation of undifferentiated cell mass.
Black (stem) rust of wheat is caused by
Alternaria solani
Ustilago nuda
Puccinia graminis
Puccinia graminis
Crocodile and penguin are similar to whale and dogfish in which one of the following features?
possess a solid single -stranded central nervous system
lay eggs and guard them till they hatch
possess a bony skeleton
possess a bony skeleton
An elaborate network of filamentous proteinaceous structures present in the cytoplasm which helps in the maintenance of cell shape is called
thylakoid
endoplasmic reticulum
plasmalemma
plasmalemma
Transport of food material in higher plants takes place through
companion cells
transfusion tissue
tracheids
tracheids
ABO blood grouping is controlled by gene I, which has three alleles and show codominance, There are six genotypes. How many phenotypes in all are possible.?
Six
Three
Four
Four
Kranz anatomy is one of the characteristics of the leaves of
potato
wheat
sugarcane
sugarcane
Jaundice is a disorder of
excretory system
skin and eyes
digestive system
digestive system
Three of the following statements about enzymes are correct and one is wrong. which one is wrong?
Enymes require optimum pH for maximal activity
Enzymes are denatured at high temperature but in certain exceptional organisms they are effective even at temperatures 80o-90o C
Enzymes are highly specific
Enzymes are highly specific
