1. Excretory System
BY Lisa Kruk, Tara
Quaghebeur, Duncan Kirk

2. Excretory System
• The primary functions of the excretory system
are;
• Get rid of wastes from the human body
• Eliminates useless by-products excreted from
cells
• Eradicates harmful chemical build-ups
• Maintains a steady, balanced chemical
concentration
• The excretory system consists of specialized
structures and capillary network

3. Kidney Structure
• The lateral surface of each kidney is convex, but its
medial side is deeply concave. The medial depression leads
into a hollow chamber; renal sinus. Hilum is the entrance of
the sinus, which passes various blood
vessels, nerves, lymphatic vessels, and the ureter. The
superior end of the ureter is expanded to form a funnel-
shaped sac; renal pelvis, which is located inside of the renal
sinus. The pelvis is sub divided into two or three tubes;
major calyces (sing, calyx) and subdivided into several
minor calyces.
• Series of small elevations project into the renal sinus
from its wall. The projections are called renal papillae, each
are pierced by tiny openings that lead into a minor calyx.

4. Kidney Structure
• The renal cortex forms a shell around the
medulla. Its tissue dips into the medulla
between adjacent renal pyramids that from
renal columns. The granular appearance of
the cortex is due to the random
arrangement of tiny random arrangement of
tiny tubules that associate with the
nephrons; functional units of the kidney.

5. Ureters Structure
• Each ureter is a tubular organ that measures about twenty-
five centimeters in length and begin at the funnel-shaped renal
pelvis.
• In the walls of the ureter there are three layers; inner
layer, middle layer, and the outer layer.
• The inner layer or mucous coat is continuous with the
linings of the renal tubules above and the urinary bladder
below.
• The middle layer or the muscular coat is composed of large
smooth muscle fibers.
• The outer layer or the fibrous coat is primarily composed of
connective tissue.

6. Ureters Structure
• Each ureter enters the bladder through a
tunnel in the bladder wall, which is angled to
prevent the urine from running back into the
ureter (reflux), when the bladder contrasts.

7. Bladder Structure
• The bladder is a spherical shaped
hollow, expandable, muscular organ located in the pelvic
girdle.
• The shape is alerted by the pressures of surrounding
organs. When the bladder is empty, the inner walls of the
bladder forms fold. When the bladder fills with urine, the
walls become smoother.
• Internal floor of the bladder includes a triangular area;
trigon. The trigone has three openings at each of its angles.
• The ureters are attached to the two posterior
openings. The anterior opening, at the apex of the
trigone, and contains a funnel-like continuation called the
neck of the bladder.

8. Bladder Structure
• Walls of the bladder consist of four bundles of smooth
muscle fibers. These muscle fibers, interlaced, form the
detrusor muscle (surrounds the bladder neck) and comprise
what is called the internal urethral sphincter.
• The internal urethral sphincter prevents urine from
escaping the bladder until the pressure inside the bladder
reaches a certain level.
• Parasympathetic nerve fibers in the detrusor muscle
function in the micturition (urination) process.

9. Urethra Structure
• The urethra transmits urine from the bladder to the exterior
of the body during urination.
• Urethra is held by the urethral s sphincter, a muscular
structure that helps keep urine in the bladder until voiding can
occur.
• The male’s urethra is about 8 Inches long and passes along
the length of the penis before emptying. As its emergence from
the bladder, the urethra passes through the prostate gland, and
seminal ducts from the testes enter the urethra at each
side, making it the pathway for the transmission of semen as well
as for discharge of urine.
• The male urethra can be divided into three sections; the
uppermost within the prostate, the next section within the urethral
sphincter, and the lowermost and longest section with the penis.

10. Urethra Structure
• The female urethra is embedded within the
vaginal wall, and its opening is situated
between the labia. It is shorter than that of a
male, it is one and a half inches long. It opens
to the outside just after passing through the
urethral sphincter.

11. Pathology
Urethritis
Urethritis is the physical examination of the males’ reproductive organ it
is checked for inflammation or swelling of the urethra.
Causes are:
• Engaging in sexual activity without using protection
• Doing sexual activity with many sexual partners
• Having history of STD’s
Symptoms include:
• Painful of difficult urination
• Purulent discharge in the reproductive organ.
Treatment:
Azithromycin, doxycycline, erythromycin, levofloxacin, metronidazole, ofl
oxacin, or tinidazole are all possible drugs that will treat this.

12. Pathology
Kidney Stones
Kidney stones are essentially stones composed of minerals and calcium that leave
the body through urination.
Causes:
• Low fluid intake
• Ingesting large amounts of animal protein
• High intake of sodium, sugars and fructose
Symptoms:
• Pain in flank and groin area
• Sweating
• Nausea
• Vomiting
Treatment: Analgesia, expulsion therapy, extracorporeal shock wave
lithotripsy, ureteroscopic surgery

13. Bibliography for pathology
• http://www.ncbi.nlm.nih.gov/pubmedhealth/
PMH0001475/
• http://www.cdc.gov/std/treatment/2010/uret
hritis-and-cervicitis.htm/