Direction of spiral of the umbilical cord

To promote clear communication, for instance, about the location of a patient's abdominal pain or a suspicious mass, anatomists and clinicians typically use imaginary lines to categorize the abdominopelvic cavity into either four quadrants or nine regions to identify organs in the cavity.
The simpler quadrants approach, which is more commonly used in medicine, subdivides the cavity with one horizontal and one vertical line that intersects at the patient's umbilicus (navel). The four quadrants...

The spinal cord resides within the protective confines of the vertebral column. It is the main pathway for information traveling between the brain and the body. It plays a fundamental role in nearly all bodily functions, from simple reflexes to complex motor movements. The spinal cord begins at the medulla oblongata at the base of the brainstem and extends downward, terminating at the conus medullaris near the first and second lumbar vertebrae. The spinal cord's length in adults is...

Once the aorta traverses the diaphragmatic plane at the aortic hiatus, it is known as the abdominal aorta. This anatomical structure is positioned leftward of the spinal column, encased within a cocoon of adipose tissue behind the peritoneal cavity. It terminates at the L4 vertebra, where it splits into the common iliac arteries. Prior to this bifurcation, the abdominal aorta gives rise to several vital branches.
The celiac trunk, a singular artery, divides into the left gastric artery, which...

The development of the vascular system in a fetus is a complex and intricate process that begins as early as 15 to 16 days post-conception. This process starts outside the embryo, specifically in the mesoderm of the yolk sac, chorion, and connecting stalk. Approximately two days later, the formation of blood vessels occurs within the embryo itself.
The initial formation of this system is facilitated by the small amount of yolk present in the ovum and yolk sac. Blood vessels originate from...

Fetal circulation is a unique system that facilitates the exchange of gases, nutrients, and waste products between the developing fetus and the mother. This intricate process takes place through a special organ called the placenta.
Two umbilical arteries transport blood from the fetus to the placenta. At the placenta, the blood absorbs oxygen and nutrients while simultaneously eliminating waste products. This oxygen-enriched and nutrient-rich blood then returns to the fetus through one...

The uterus, commonly called the womb, is a vital reproductive organ in females designed to provide a nurturing environment for the implantation and growth of an embryo. It is shaped like a hollow pear and positioned between the urinary bladder and the rectum. The uterus's structure allows it to support and protect a developing fetus throughout pregnancy.
The uterus is securely anchored within the pelvic cavity by paired broad ligaments on either side. It is further stabilized by three pairs of...