True regarding unconjugated bilirubin is -
Unconjugated bilirubin 

Unconjugated bilirubin is highly lipid soluble (lipophilic).
It is insoluble in water and tightly bound to albumin → cannot be excreted in urine.
Unbound fraction, which is increased in hemolytic reactions (e.g. erythroblastosis fetalis), can cross blood-brain barrier because of lipophilic nature and can cause brain damage of newborn → Kernicterus.

Conjugated bilirubin

Conjugated bilirubin is water soluble and only loosely bound to albumin and thus is easily filtered by glomeruli and excreted in urine.