Kidneys Flashcards
(21 cards)
Hilum
The entry and exit site for structures servicing the kidneys: vessels, nerves, lymphatics, and ureters.
Renal capsule
A thin membranous sheath that covers the outer surface of each kidney. The capsule is composed of tough fibers, chiefly collagen and elastin (fibrous proteins), that help to support the kidney mass and protect the vital tissue from injury.
Renal cortex
The outer portion of the renal cavity between the renal capsule and the renal medulla.
Renal medulla
The innermost part of the kidney. The renal medulla is split up into a number of sections, known as the renal pyramids.
Renal pyramid
Any of the triangular sections of tissue that constitute the medulla, or inner substance, of the kidney. The pyramids consist mainly of tubules that transport urine from the cortical, or outer, part of the kidney, where urine is produced, to the calyces, or cup-shaped cavities in which urine collects before it passes through the ureter to the bladder.
Nephrons
One of the million tiny structural and functional units of the kidney that filters blood and forms urine.
Renal columns
An extension of the renal cortex in between the renal pyramids. It allows the cortex to be better anchored. Each column consists of lines of blood vessels and urinary tubes and a fibrous material.
Renal pelvis
The funnel-like end of a ureter where it enters the kidney and where urine collects before it is transported through the ureter.
Blood
A body fluid in humans and other animals that delivers necessary substances such as nutrients and oxygen to the cells and transports metabolic waste products away from those same cells. In vertebrates, it is composed of blood cells suspended in blood plasma.
Arteries
A type of blood vessel that carries blood away from the heart and toward the lungs or body.
Veins
A type of blood vessel that carries blood toward the heart from the lungs or body.
Vena cava
A large vein carrying deoxygenated blood into the heart. There are two in humans, the inferior vena cava (carrying blood from the lower body) and the superior vena cava (carrying blood from the head, arms, and upper body).
Urea
Waste product of protein catabolism that is mainly filtered from blood in the kidneys and excreted in urine.
Uric acid
A waste product of nucleic acid catabolism that is mainly filtered from blood by the kidneys and excreted in urine.
Glomerulus
A network of capillaries in the nephron of a kidney where substances are filtered out of the blood.
Glomerular capsule
A structure surrounding the glomerulus of a nephron in a kidney, also known as the Bowman’s capsule, into which substances that are filtered out of blood are passed to the renal tubule.
Renal tubule
A tubular structure of a nephron in a kidney through which filtered substances pass and where some filtered substances are reabsorbed by the blood and additional substances are secreted from the blood.
Proximal convoluted (coiled) tubule
The portion of the nephron that lies between the glomerular capsule and the loop of Henle and functions especially in the resorption of sugar, sodium and chloride ions, and water from the glomerular filtrate.
Distal convoluted tubule
A portion of kidney nephron between the loop of Henle and the collecting tubule. It is the part of the nephron and that is concerned especially with the concentration of urine.
Peritubular capillary network
Tiny blood vessels, supplied by the efferent arteriole, that travel alongside nephrons allowing reabsorption and secretion between blood and the inner lumen of the nephron.
pH
A measure of the acidity or basicity of aqueous or other liquid solutions. The term translates the values of the concentration of the hydrogen ion in a scale ranging from 0 and 14. In pure water, which is neutral (neither acidic nor alkaline), the concentration of the hydrogen ion corresponds to a pH of 7. A solution with a pH less than 7 is considered acidic; a solution with a pH greater than 7 is considered basic, or alkaline.
