The Pacific Ocean is the largest ocean in the world at 155,557,000 sq km.   The Atlantic Ocean is the second largest ocean in the world at 76,762,000 sq km.
The cause of major depressive disorder is a combination of brain chemistry, family history, and psychosocial environment. It is not certain which of these factors dominates, but abnormal levels of the neurotransmitters norepinephrine, serotonin, and dopamine are closely linked with depression.
A major depressive episode is a period characterized by the symptoms of major depressive disorder: primarily depressed mood for two weeks or more, and a loss of interest or pleasure in everyday activities, accompanied by other symptoms such as feelings of emptiness, hopelessness, anxiety, worthlessness, guilt and/or irritability, changes in appetite, problems concentrating, remembering details or making decisions, and thoughts of or attempts at suicide. Insomnia or hypersomnia, aches, pains, or