Its head.
No, it is not part of the circulatory system, it is protecting you from the environment, to help keep homeostasis( the body in stable condition)
A gallon is NOT part of the metric system. A gallon is a part of the Imperial system and contains 4 quarts (or 8 pints)
the brain.
Since it hangs in the back of the throat and keeps food from going into your lungs, I would say it is part of the digestive system, found within the alimentary canal.
Yes, the mouth is an organ. It is part of the digestive system.
An insect has a brain as part of its nervous system. The brain receives and interprets sensory impulses from all ganglia on the insect's body.
The Digestive System
Most insects have a dorsal tube that is divided into different chambers. This is what serves as the heart in an insect. The dorsal tube is located toward the thorax which is in the midsection of the insect.
The skin is part of the Integumentary System, and is the largest organ in the body.
The parathyroid is part of the Hormonal System. It is a gland that sits with the thyroid gland.
Imago
The penis is primarily part of the Reproductive System but is also part of the Urinary System because the penis has two primary functions.
The dorsal cavity contains the spinal cord, which is part of the central nervous system. Every body cavity contains some structures of the nervous system.
You have the information mixed up. The nervous system includes the brain, spinal cord, spinal nerves, and all peripheral nerves. There is no "part of the brain" that contains this body system.
It is the brain part of the human body that contains the most neonates.
The thorax
The part that contains your message is the body.