Digestive 
Blood
Cardiovascular
Dermatology
Genitourinary,
Hormones
Infections
Oncology and
Musculo-skeletal
Mental health and
Parasites
Respiratory
Senses
Various
A thrombus is a blood clot (thick blood turns from liquid to solid) due to platelet accumulation or cholesterol that forms in a vein or artery and remains there.
An embolus is a thrombus that travels from the site where it formed another place in the body.
A thrombus or embolus may occur in a blood vessel and obstruct blood flow there, preventing the supply of oxygen to tissues.
When tissue is destroyed due to not receiving oxygen, the destruction (infarction) or death (necrosis) of the tissues in that area occurs.
