bms 231: 2015/2016 anatomy of the urinary system dr sobia ikram dr aqeela bano dr sadia farhan
TRANSCRIPT
BMS 231: 2015/2016
Anatomy of the Urinary System
DR SOBIA IKRAMDR AQEELA BANODR SADIA FARHAN
Table of Contents
1. Objectives for this lesson2. Functions and Organisation of the Urinary
system3. Location and External anatomy of the
kidney.4. Internal Gross anatomy and parts of the
kidney5. Parts of the nephron and general
functioning of the nephron..6. Definition ,function and location of the
Urinary Bladder, ureters and urethra.
Objectives
When you finish this lesson, you should be able to
• Describe the Functions and Organisation of the Urinary system .
• Understand the Location and External Anatomy of the kidney.
• Identify the Internal gross Anatomy and parts of the kidney.
• Understand the parts of the nephron and their general functioning.
• Define and explain the location and functions of the urinary bladder, ureters and urethra.
Functions of the urinary system
1. Remove nitrogenous wastes (urine)2. Maintain electrolyte, acid-base, and
fluid balance of blood3. Homeostatic organ4. Acts as blood filter5. Release hormones: calcitriol &
erythropoietin
Organs of the Urinary System
5
• Kidneys
• Ureters
• Urinary bladder
• Urethra
kidneys• The Kidneys are the blood
filtering organs of the urinary system.
• The kidneys are fist-sized, bean shaped structures that remove nitrogenous wastes (urine).
• The kidneys regulate the amount of water, salts and other substances in the blood.
Location and External Anatomy•Located Retroperitonealy.
•Lateral to T 12 – L 3 Vertebra
L3
HILUM
•Is a depression present On the medial surface of each kidney.•Vessels and nerves enter and exit from the hilum.
RENAL CAPSULE is the membrane that surrounds the kidney.
AN AVERAGE KIDNEY is about 12 cm tall, 6 cm wide, 3
cm thick
Location and External Anatomy
External anatomy of the Kidney
9
12 cm
6cm
3cm
10
Internal Gross Anatomy of the KidneySagittal Section through the Kidney shows
1.Renal cortex
2.Renal Medulla Renal pyramid
3.Renal pelvis Major calices Minor calices
renal capsule
renal cortex
renal medulla
renal pelvis
renal pyramids
ureter
Internal Gross Anatomy of the Kidney
Nephrons
• They are the functioning unit of the kidney
• About 1 million nephrons are in a kidney.
1. Bowman’s capsule2. Glomerulus3. Proximal convoluted tubule4. Loop of Henle5. Distal convoluted tubule6. Collecting tubule
Parts of nephron
The ureters are tubes made of smooth muscles that carry urine from the kidneys to the urinary bladder.
Ureter
• Superiorly• Continuous with the
renal pelvis
• Inferiorly• Pass through the
abdominal cavity, behind the peritoneum, into the pelvic cavity where they enter the posterior wall of the bladder
• 25-30 cm in length17
Ureter
Urinary bladder
Sagittal section of male and female bladder
Urinary Bladder
Wall of bladder
– Mucosa ( inner)
– Muscular layer (middle )• Detrusor
– Adventitia (outer)
Internal urethral sphincter:
• Smooth muscle• Involuntary control• More superiorly located
External Urethral sphincter:
• Skeletal muscle• Voluntary control• Posteriorly located
Sphincters of the Bladder
• IN FEMALES– Length of 3–4 cm
• IN MALES – 20 cm in length – three regions anatomically
– Prostatic urethra• Passes through the prostate gland
– Membranous urethra• Through the urogenital diaphragm
– Spongy (penile) urethra• Passes through the length of the penis
Urethra
26
Frontal view of female urethra
Frontal view of female urethra