Answer 2: Snails are really interesting! Most snails are considered to be hermaphrodites and have both male and female reproductive organs. Snails are able to reproduce when they are 1-year-old (they live to be about 5-7 years old but some as long as 25 years!) at which time they must find a snail partner to mate with.
The posterior descending artery, which is also known as the posterior inter-ventricular artery, is a branch of one of the heart's main arteries. In most people, the posterior descending artery branches away from the right coronary artery, which is called right coronary artery dominance. In left coronary artery dominance, the posterior descending artery branches away from the left circumflex artery.
The first branch of the subclavian artery; it runs up the back of the neck via foramina in the transverse processes of the cervical vertebrae and enters the cranial cavity through the foramen magnum. The right and left vertebral arteries merge along the ventral surface of the hindbrain to become the basilar artery. Branches of the vertebral artery include the anterior and posterior spinal arteries and the posterior inferior cerebellar artery. The vertebral arteries carry about 20% of the brain's blood supply, feeding the brainstem, cerebellum, and most of the posterior cerebral hemispheres.