The surrounding white matter contains columns of nerve fibers axon bundles that carry sensory information to the brain from the rest of the body ascending tracts and columns that carry motor impulses from the brain to the muscles descending tracts.
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Common Health Topics. Biology of the Nervous System. Test your knowledge. A brain abscess is a pocket of pus in the brain. Which of the following is NOT a common cause of a brain abscess? More Content. Click here for the Professional Version. How the Spine Is Organized A column of bones called vertebrae make up the spine spinal column.
One at the front motor or anterior root of the spinal cord. Was This Page Helpful? Yes No. Blockage of the Blood Supply to the Spinal Cord. Compression of the Spinal Cord. The peritoneal cavity reduces friction between the abdominal and pelvic organs and the body wall. Therefore, serous membranes provide additional protection to the viscera they enclose by reducing friction that could lead to inflammation of the organs.
Ancient Greek and Latin words are used to build anatomical terms. The serous membranes have two layers—parietal and visceral—surrounding a fluid filled space. Serous membranes cover the lungs pleural serosa , heart pericardial serosa , and some abdominopelvic organs peritoneal serosa.
In which direction would an MRI scanner move to produce sequential images of the body in the frontal plane, and in which direction would an MRI scanner move to produce sequential images of the body in the sagittal plane? Again, if the body were supine or prone, to produce sagittal sections, the scanner would move from left to right or from right to left to divide the body lengthwise into left and right portions.
If a bullet were to penetrate a lung, which three anterior thoracic body cavities would it enter, and which layer of the serous membrane would it encounter first? The bullet would enter the ventral, thoracic, and pleural cavities, and it would encounter the parietal layer of serous membrane first. Skip to content An Introduction to the Human Body. Learning Objectives By the end of this section, you will be able to: Demonstrate the anatomical position Describe the human body using directional and regional terms Identify three planes most commonly used in the study of anatomy Distinguish between the posterior dorsal and the anterior ventral body cavities, identifying their subdivisions and representative organs found in each Describe serous membrane and explain its function.
Anatomical Position To further increase precision, anatomists standardize the way in which they view the body. Regions of the Human Body. The human body is shown in anatomical position in an a anterior view and a b posterior view. The regions of the body are labeled in boldface.
Directional Terms Certain directional anatomical terms appear throughout this and any other anatomy textbook Figure. Anterior or ventral Describes the front or direction toward the front of the body. The toes are anterior to the foot.
Posterior or dorsal Describes the back or direction toward the back of the body. The popliteus is posterior to the patella. Superior or cranial describes a position above or higher than another part of the body proper. The orbits are superior to the oris. Inferior or caudal describes a position below or lower than another part of the body proper; near or toward the tail in humans, the coccyx, or lowest part of the spinal column. The pelvis is inferior to the abdomen.
Lateral describes the side or direction toward the side of the body. The thumb pollex is lateral to the digits. Medial describes the middle or direction toward the middle of the body.
The hallux is the medial toe. Proximal describes a position in a limb that is nearer to the point of attachment or the trunk of the body. The brachium is proximal to the antebrachium.
Distal describes a position in a limb that is farther from the point of attachment or the trunk of the body.
The crus is distal to the femur. Superficial describes a position closer to the surface of the body. The skin is superficial to the bones.
Deep describes a position farther from the surface of the body. The brain is deep to the skull. Directional Terms Applied to the Human Body. They usually contains protective membranes and sometimes bones that protect the organs.
Anatomical terminology for body cavities : Humans have multiple body cavities, including the cranial cavity, the vertebral cavity, the thoracic cavity containing the pericardial cavity and the pleural cavity , the abdominal cavity, and the pelvic cavity. In mammals, the diaphragm separates the thoracic cavity from the abdominal cavity.
The dorsal cavity is a continuous cavity located on the dorsal side of the body. It houses the organs of the upper central nervous system, including the brain and the spinal cord.
The meninges is a multi-layered membrane within the dorsal cavity that envelops and protects the brain and spinal cord. The cranial cavity is the anterior portion of the dorsal cavity consisting of the space inside the skull. This cavity contains the brain, the meninges of the brain, and cerebrospinal fluid. The vertebral cavity is the posterior portion of the dorsal cavity and contains the structures within the vertebral column.
These include the spinal cord, the meninges of the spinal cord, and the fluid-filled spaces between them. This is the most narrow of all body cavities, sometimes described as threadlike. The ventral cavity, the interior space in the front of the body, contains many different organ systems.
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