Portal:Anatomy

An anatomical variation, anatomical variant, or anatomical variability is a presentation of body structure with morphological features different from those that are typically described in the majority of individuals. Anatomical variations are categorized into three types including morphometric (size or shape), consistency (present or absent), and spatial (proximal/distal or right/left).

Variations are seen as normal in the sense that they are found consistently among different individuals, are mostly without symptoms, and are termed anatomical variations rather than abnormalities.

Anatomical variations are mainly caused by genetics and may vary considerably between different populations. The rate of variation considerably differs between single organs, particularly in muscles. Knowledge of anatomical variations is important in order to distinguish them from pathological conditions. (Full article...)

The human vertebral column and its regions

The vertebral column, also known as the backbone or spine, is part of the axial skeleton. The vertebral column is the defining characteristic of a vertebrate in which the notochord (a flexible rod of uniform composition) found in all chordates has been replaced by a segmented series of bone: vertebrae separated by intervertebral discs. Individual vertebrae are named according to their region and position, and can be used as anatomical landmarks in order to guide procedures such as lumbar punctures. The vertebral column houses the spinal canal, a cavity that encloses and protects the spinal cord.

There are about 50,000 species of animals that have a vertebral column. The human vertebral column is one of the most-studied examples. Many different diseases in humans can affect the spine, with spina bifida and scoliosis being recognisable examples.

The general structure of human vertebrae is fairly typical of that found in mammals, reptiles, and birds. The shape of the vertebral body does, however, vary somewhat between different groups. (Full article...)

1. Human urinary system: 2. Kidney, 3. Renal pelvis, 4. Ureter, 5. Bladder, 6. Urethra. (Left side with frontal section) 7. Adrenal gland Vessels: 8. Renal artery and vein, 9. Inferior vena cava, 10. Abdominal aorta, 11. Common iliac artery and vein With transparency: 12. Liver, 13. Large intestine, 14. Pelvis

The bladder is a hollow organ in humans and other vertebrates that stores urine from the kidneys before disposal by urination. In humans the bladder is a distensible organ that sits on the pelvic floor. Urine enters the bladder via the ureters and exits via the urethra. The typical adult human bladder will hold between 300 and 500 ml (10.14 and 16.91 fl oz) before the urge to empty occurs, but can hold considerably more.

The Latin phrase for "urinary bladder" is vesica urinaria, and the term vesical or prefix vesico - appear in connection with associated structures such as vesical veins. The modern Latin word for "bladder" – cystis – appears in associated terms such as cystitis (inflammation of the bladder). (Full article...)

ʿAlāʾ al-Dīn Abū al-Ḥasan ʿAlī ibn Abī Ḥazm al-Qarashī al-Dimashqī (Arabic: علاء الدين أبو الحسن عليّ بن أبي حزم القرشي الدمشقي), known as Ibn al-Nafīs (Arabic: ابن النفيس), was an Arab polymath whose areas of work included medicine, surgery, physiology, anatomy, biology, Islamic studies, jurisprudence, and philosophy. He is known for being the first to describe the pulmonary circulation of the blood. The work of Ibn al-Nafis regarding the right sided (pulmonary) circulation pre-dates the later work (1628) of William Harvey's De motu cordis. Both theories attempt to explain circulation. 2nd century Greek physician Galen's theory about the physiology of the circulatory system remained unchallenged until the works of Ibn al-Nafis, for which he has been described as "the father of circulatory physiology".

As an early anatomist, Ibn al-Nafis also performed several human dissections during the course of his work, making several important discoveries in the fields of physiology and anatomy. Besides his famous discovery of the pulmonary circulation, he also gave an early insight of the coronary and capillary circulations. He was also appointed as the chief physician at al-Naseri Hospital founded by Sultan Saladin. (Full article...)