Which cell organelle is covered by only one unit membrane ?
Nucleus
Plastids
Mitochondria
Lysosome
The S-phase of cell cycle is characterized by:
duplication of chromosome
shotening of chromosome
duplication of DNA
duplicatin of centriole
Core of chlorophyll is formed by
Fe
Mn
CH3
Mg
D.
Mg
The chlorophylls are basically chelate salts of magnesium (Mg). The chlorophyll has a molecular formula C55H72O5N4Mg. This molecule is distinguishable into head of size 15 x 15 Å and a tail length of 20 Å. The head is made up of prophyrin ( a tetraphyrrole closed ring derivative) and the tail of phytol.
Phytotron is :
a controlled condition chamber for tissue
leaf culture process
special culture of plants
root culture process
If centromere is the middle, the chromosome is called :
sub-metacentric
metacentric
acentric
telocentric
Which hormone is responsible for mobilization of storage food during seed germination ?
Auxin
Gibberellin
Cytokinin
Ethylene