[True knot in an umbilical cord]

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...

During early development, the embryo forms two types of connective tissues— the mesenchyme and mucoid connective tissue.
The mesenchyme is the first connective tissue that emerges in the developing embryo. It consists of loosely arranged multipotent mesenchymal cells and reticular fibers in the extracellular matrix. This loose arrangement allows easy migration of cells, which is essential for germ layer positioning, patterning, and organ morphogenesis during embryonic development. Mesenchyme is...

The spinal cord is the body’s major nerve tract of the central nervous system, communicating afferent sensory information from the periphery to the brain and efferent motor information from the brain to the body. The human spinal cord extends from the hole at the base of the skull, or foramen magnum, to the level of the first or second lumbar vertebra.

The uterine or fallopian tubes function as the conduit through which oocytes travel from the ovaries to the uterus. Each fallopian tube measures approximately 10 to 13 cm long and is anatomically divided into the infundibulum, ampulla, isthmus, and interstitial part (or intramural segment). The infundibulum is characterized by its funnel shape and features extensions called fimbriae which reach towards the peritoneal cavity. These fimbriae play a critical role during ovulation as they extend...

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...

In human anatomy, anastomosis refers to a connection or opening between two things, particularly between blood vessels or other tubular structures. The term is derived from the Greek term 'anastomosis,' which means 'outlet' or 'opening.' This natural network of connections plays a critical role in the survival and functionality of the human body.
Anastomoses can be formed at arterial, venous, and lymphatic vessels.
Arterial Anastomosis: These occur between arteries. They are most common in...