The kidneys are two reddish-brown bean-shaped organs found in vertebrates.

What are blood vessels?

Blood vessels are channels that carry blood throughout your body. They form a closed loop, like a circuit, that begins and ends at your heart. Together, the heart vessels and blood vessels form your circulatory system. Your body contains about 60,000 miles of blood vessels.

There are three types of blood vessels:

The kidneys are bilateral organs placed retroperitoneally in the upper left and right abdominal quadrants and are part of the urinary system. Their shape resembles a bean, where we can describe the superior and inferior poles, as well as the major convexity pointed laterally, and the minor concavity pointed medially.

The main function of the kidney is to eliminate excess bodily fluid, salts and byproducts of metabolism – this makes kidneys key in the regulation of acid-base balance, blood pressure, and many other homeostatic parameters.

Key facts about the kidney

The testes and epididymis are paired structures, located within the scrotum. The testes are the site of sperm production and hormone synthesis, while the epididymis has a role in the storage of sperm.

In this article, we shall look at the anatomy of the testes and epididymis – their structure, vasculature, innervation and clinical correlations.

The left lung does not have a middle lobe in contrast to the right lung, however it does have a projection of the upper lobe called lingula. The lingula on the left lung is as the same as the middle lobe in the right lung.

Each lung is separated into lobes branching off the main bronchus; the right lung has three lobes, while the left has only two lobes. As the bronchi branch out, the total area of the two new branches is larger than its parent bronchus, making it extremely easy for the air to rush into the lung

The spinal cord is a tubular bundle of nervous tissue and supporting cells that extends from the brainstem to the lumbar vertebrae. Together, the spinal cord and the brain form the central nervous system.

In this article, we shall examine the macroscopic anatomy of the spinal cord – its structure, membranous coverings and blood supply.

For information regarding the internal structure of the spinal cord, see the grey matter of the spinal cord.

The posterior border is thick and extends from the C7 to the T10 vertebra, which is also from the apex of the lung to the inferior border. The three surfaces of the lung include the costal, medial, and diaphragmatic surfaces. The costal surface is covered by the costal pleura and is along the sternum and ribs.

Liver fibrosis is the excessive accumulation of extracellular matrix proteins including collagen that occurs in most types of chronic liver diseases. Advanced liver fibrosis results in cirrhosis, liver failure, and portal hypertension and often requires liver transplantation. Our knowledge of the cellular and molecular mechanisms of liver fibrosis has greatly advanced. Activated hepatic stellate cells, portal fibroblasts, and myofibroblasts of bone marrow origin have been identified as major collagen-producing cells in the injured liver.