What structure is marked A? A HOE

The brain is the part of the human body responsible for controlling its overall functions. The brain forms the central part of the human nervous system and weighs around one to two kilograms in the adult human body. In order to regulate the body activities, the brain is connected to all the sensory and motor nerves through the spinal cord. The brain receives and sends the nerve signals to the various body parts through its connection with the spinal cord.. The communication between the brain and the rest of the body takes place via specialized cells contained within the brain, called as the neurons. These neurons transmit the messages in the form of electrical signals to and from the brain. The brain consists of five main components which includes the brain stem, cerebellum, thalamus, cerebrum and corpus callosum. In order to protect the nervous system from the accidental forces, the brain is contained within the cranial cavity and suspended in the cerebrospinal fluid.