At cat shows, the head sets the standard for the body in a physical sense. Many judges spend more time studying the head of the cat than any other part of the body. While the points allotted to the rest of the cat should certainly be considered, there can be no argument that the head is of utmost importance.
The largest part of the head is the brain. The brain is located in the cranial cavity and is an enlarged and highly modified continuation of the spinal cord. The nervous system begins and ends here. The brain is divided into two egg-shaped hemispheres whose surfaces are marked by folds which are both thick and numerous. The hemispheres make up the greatest part of the developed brain, and the brain itself is held by the cranial cavity, which is designed to cushion and protect the brain. The rear wall of this compartment is formed by the occiptal bone, whose lower section is perforated by an opening that is almost circular. This opening is for the spinal cord.
Now the brain would be almost useless if it couldn't be kept informed of everything that happens in the body. This is where the cranial nerves come in. There are twelve pairs of cranial nerves. These of these -- optic, olfactory, and auditory -- are there purely to interpret the special sense of sight, scent, and sound. Five of the pairs -- oculomotor, abducens, hypoglossal, trochlear, and spinal accessory -- are for motor function. The remaining four -- trigeminal, facial, glosso-pharyngeal, and vagus -- are for both sensory and motor functions.
The head of the cat is the seat of most of the major functions of the body. Air intake, food intake, excretory abilities and many other functions are seated here. Though some of these processes are carried out in depth in other areas of the body (such as digestion), they are started in the head. For example, the head produces some digestive enzymes in the salivary glands, and so digestion begins in the mouth.
The head, by way of the pituitary gland (the principle control gland in the body), also influences the endocrine system. Almost a dozen separate function are controlled by hormones manufactured, released, or stored by the pituitary gland. Some of these many functions include growth and even the onset of estrus in female cats.
As the head is solely responsible for acquiring the oxygen and food the body needs, the head should never be ignored during your study of the cat. The brain does so much for the body, but it itself exists on the most simple of chemicals produced in the body. The brain, and the head, asks for very little in return for supplying essential life to the body.
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