Kidneys accommodate between 600 to 800 ml of
urine at maximum capacity.
The kidneys are bean-shaped organs that
serve several essential regulatory roles in Urethra
vertebrates and located in the abdominal
cavity. It is a tube that conveys urine from the
The left kidney is located at the vertebral urinary bladder to the outside of the body.
level T12 to L3, and the right is slightly Its wall is lined with mucous membranes
below the diaphragm and posterior to the and contains a relatively thick layer of
liver. smooth muscle tissue.
The kidneys, unlike the other organs of the It contains numerous mucous glands,
abdominal cavity, are located posterior to called urethral glands that secrete mucus
the peritoneum and touch the muscles of into the urethral canal.
The kidneys are surrounded by a layer of
adipose that holds them in place and It is a liquid (an aqueous solution)
protects them from physical damage. produced by the kidneys to remove waste
The kidneys filter metabolic wastes, products from the bloodstream.
excess ions, and chemicals from the blood It is yellowish in color fluid due to
to form urine. presence of urochrome pigment.
It consists primarily of water (91-96%),
with organic solutes including urea,
These are a pair of tubes that carry urine creatinine, uric acid, and trace elements.
from the kidneys to the urinary bladder. The pH of human urine ranges from 5.5 to
They are about 10 to 12 inches long. 7, averaging around 6.2 and it is acidic in
Gravity and peristalsis of smooth muscle nature.
tissue in the walls of the ureters move Average urine production in adult humans
urine toward the urinary bladder. is about 1-2 L per day, depending on state
The ends of the ureters extend slightly into of hydration, activity level, environmental
the urinary bladder and are sealed at the factors, weight, and the individual"s health.
point of entry to the bladder by the NERVOUS SYSTEM
These valves prevent urine from flowing It consists of the brain, spinal cord,
back towards the kidneys. sensory organs, and all of the nerves that
connect these organs with the rest of the
Urinary bladder body.
It is a sac-like hollow elastic organ that Together, these organs are responsible for
functions as the body’s urine storage tank. the control of the body and
communication among its parts.
It is located along the body’s midline at
the inferior end of the pelvis. The brain and spinal cord form the
control center known as the Central
The urinary bladder functions as a storage
Nervous System (CNS), where
vessel for urine to delay the frequency of
information is evaluated and decisions
It is an elastic organs and is able to
The sensory nerves and sense organs of
increase its volume greatly to
the peripheral nervous system (PNS)
monitor conditions inside and outside of