Function-The kidneys are located on either side of the spinal column near the lower back. There main
purpose is filtering blood by removing nitrogenous wastes. They also regulate blood pressure in a
process called osmoregulation and also assist with the production of red blood cells.
Structure- They are bean shaped usually 10 cm long and 6.5 cm wide. Each kidney has an outer
cortex and an inner medulla. The kidney is supplied with oxygenated blood from the renal artery and
drained of deoxygenated blood because of the renal vein. In addition, urine produced by the kidney
as part of its excretory function, drains from narrow “tubules” and the ureter which is connected to
The renal capsule is the membrane that covers the kidney. It directly covers the renal cortex, which
forms the outer stratum. Capsule
The cortex of the kidney is the outer section which covers the internal medulla. It is visible near the
outer edge of the cross-sectioned kidney. It is composed of blood vessels and urine tubes as well it is Cortex
supported by a fibrous matrix.
The calyces are the recess' in the internal medulla of the kidney which encloses the pyramids. They
divide the sections of the kidney anatomically. Distinction is made between major calyces and minor Calyx
Renal columns are lines on the kidney matrix which support the cortex of the kidney. They are
composed with lines of blood vessels and urinary tubes as well as fibrous and cortical material.
Parts of A Kidney
Renal pyramids are cone shaped segments within the internal medulla of the kidney. The pyramids The skin releases sweat, this cools the body and regulates the concentration of salt.
contain the secreting apparatus and tubules. They can also be known as the malphighian pyramids. Kidney
The liver like a kidney also helps in excreting wastes from the body in a variety of processes. Liver
The renal sinus is the pouch within the kidney which houses the renal pyramid that I just explained. has a high concentration of a small organelle called peroxisome, responsible for the breakdown of
Nerves and blood vessels pass into the renal sinus through the hilus. Renal Sinus Liver several toxic substances. The liver main purpose is to absorb drugs and other poisonous substances
in the blood and changes their chemical structure to make them less toxic and easier to digest.
The hilus is the small opening in the middle of the concave medial border of the kidney. Nerves and
blood vessels pass through the hilus into the renal sinus within. Hilus
The ureters are muscular ducts that propel urine from the kidneys to the urinary bladder. Valves
Renal Artery Ureters known as ureterovesical valves prevent the backflow of urine. In the female, the ureters pass through
the mesometrium on the way to the urinary bladder.
Parts And Functions The bladder is the organ that collects urine excreted by the kidneys prior to disposal by urination.
Filtration-liquid that has been passed through a filter.
Urine enters the bladder via the ureters and exits via the urethra. In males, the base of the bladder
Kidney-either of a pair of bean-shaped organs in the back part of the abdominal cavity that form and Bladder lies between the rectum and the pubic symphysis. It is superior to the prostate, and separated from
excrete urine the rectum by the rectovesical excavation. In females, the bladder sits inferior to the uterus and
Ureter-a muscular duct or tube conveying the urine from a kidney to the bladder or cloaca.
Excretory System anterior to the vagina. It is separated from the uterus by the vesicouterine excavation.
Nephron-the filtering and excretory unit of the kidney, consisting of the glomerulus and tubules. The urethra is a tube that connects the bladder to the outside of the body. The urethra has an
excretory function in both sexes to pass urine to the outside, and also a reproductive function in the
Urethra male, as a passage for semen during sexual activity. The external urethral sphincter is a striated
Urethra-the membranous tube that extends from the urinary bladder to the exterior and that in the
male conveys semen as well as urine. muscle that allows voluntary control over urine.
Urine-the liquid-to-semisolid waste matter excreted by the kidneys, in humans being a yellowish, Nephron is the main part of Kidney. There are about one million nephrons per kidney. The role of
slightly acid, watery fluid. nephrons is to make urine. Its main function is to manage water and soluble substances by filtering
Vocab Nephrons the blood, reabsorbing what is needed and excreting the rest as urine. Nephrons eliminate wastes
Bladder-a distensible, muscular and membranous sac, in which the urine is retained until it is from the body and regulate blood volume and pressure.
discharged from the body.
Renal Artery-either of two branches of the abdominal aorta of which each supplies one of the
kidneys, arises immediately below the origin ofthe corresponding superior mesenteric artery, divides
into four or five branches which enter the hilum of the kidney, and gives off smaller branches to the
ureter, adrenal gland, and adjoiningstructures Excrcetion- Excretion happens in living organisms and cells and it is the process of eliminating or
expelling waste matter
Renal Vain-a short thick vein that is formed in each kidney by the convergence of the interlobar veins,
leaves the kidney through the hilum,and empties into the inferior vena cava
Sweat Glands-one of the minute, coiled, tubular glands of the skin that secrete sweat.
Carson Wlad Tuesday, February 16, 2010 10:16:49 AM MT (CA)