TLS Online TPP Program

#Id: 5845


Complete restoration - Conservationists attempt to return a habitat to its condition prior to the disturbance. 


#Unit 10. Ecological Principles #Ecological succession, Island biogeography and Applied ecology #Part B Pointers
More Pointers
TLS Online TPP Program

#Id: 7850

#Unit 1. Molecules and their Interaction Relevant to Biology

The 6-membered cyclic form of sugars is usually called the “pyranose” form in reference to the cyclic ether pyran.


TLS Online TPP Program

#Id: 7852

#Unit 1. Molecules and their Interaction Relevant to Biology

The pyranose forms of the sugars are more stable than the furanose forms in solution.


TLS Online TPP Program

#Id: 7853

#Unit 1. Molecules and their Interaction Relevant to Biology

Thus, D glucose in aqueous solution exists as an equilibrium mixture of 5 compounds. The pyranose form predominates in solution.

aD glucofuranose (0.5%)

aD-glucopyranose (37%)

aldehydo- -glucose (0.003%)

bD-glucofuranose (0.5%)

bD-glucopyranose (62%)

TLS Online TPP Program

#Id: 7854

#Unit 1. Molecules and their Interaction Relevant to Biology

The optical activity of a stereoisomer is expressed quantitatively by its optical rotation.
The number of degrees by which plane-polarized light is rotated on passage through a given path length of a solution of the compound at a given concentration.

TLS Online TPP Program

#Id: 7855

#Unit 1. Molecules and their Interaction Relevant to Biology

Optical rotation

TLS Online TPP Program

#Id: 7856

#Unit 1. Molecules and their Interaction Relevant to Biology

When equal amounts of extrorotatory and levorotatory isomers are present, the resulting mixture becomes optically inactive because the optical activities of each isomer cancel each other.
Such a mixture is called a racemic or dl-mixture or (±)-conglomerate and this process of converting an optically active compound into the racemic modification is known of racemization.