Active factor XII then activates  factor XI, & active factor XI activates factor IX.

TLS Online TPP Program

#Id: 7836

#Unit 1. Molecules and their Interaction Relevant to Biology

A carbon atom with four different substituents is said to be asymmetric, and asymmetric carbons are called chiral centers

Chiral carbon most distant from the carbonyl carbon has the same configuration as the chiral carbon in D-glyceraldehyde.

TLS Online TPP Program

#Id: 7838

#Unit 1. Molecules and their Interaction Relevant to Biology

For monosaccharides with two or more asymmetric carbons, the prefix d or l refers to the configuration of the highest numbered asymmetric carbon (the asymmetric carbon farthest from the carbonyl carbon).

TLS Online TPP Program

#Id: 7839

#Unit 1. Molecules and their Interaction Relevant to Biology

TLS Online TPP Program

#Id: 7840

#Unit 1. Molecules and their Interaction Relevant to Biology

Stereoisomers that are mirror images of each other are called enantiomers

TLS Online TPP Program

#Id: 7841

#Unit 1. Molecules and their Interaction Relevant to Biology

Isomers that have opposite configurations at one or more of the chiral centers but that are not mirror images of each other are called diastereomers

TLS Online TPP Program

#Id: 7842

#Unit 1. Molecules and their Interaction Relevant to Biology

Two sugars that differ in configuration at only one chiral center are described as epimers.