Mutation are two types somatic and germ cell mutation...as there is mutation in germ cell it will alter the normal behavior and produce variation !
random fertilization also causes variation as different setup of genes meets with another different...so chances of variation increases !
and third crossing over is in meiosis when chiasmata forms....so in this two homologous chromosome attach to each other and on separation ... some part exchange so leads to variation !
In the trp (tryptophan) operon, the* repressor protein *binds to the product of the trp operon synthesis pathway, called *tryptophan *forming the active *corepresser *
Immunosuppressants, by it's name itself, suppresses or inhibits the immune system for functioning in a certain amount of time. It is administered usually during transplant surgeries, so that the new cells of the organ does not get killed by the recipient's immune system.
Fat is less soluble in water compared to phospholipids.
This is because, fat is made up of three molecules of fatty acids which are not polar in nature at all, thus they mixed very poorly with water.
Phospholipids on the other hand has its molecules divided into two distinct regions, the head and the tail region. The head region is hydrophillic and it is polar in nature, that is, it mixes well with water. The tail region is made up of the fatty components and it is hydrophobic.
Because of this difference in structure, phospholipid will dissolve better in water.