ANATOMY(4201)COHORT 4

DIPLOMA IN MEDICAL

SCIENCE

SCHOOL OF ALLIED SCIENCE

WINDFIELD INTERNATIONAL

COLLEGE

URINARY SYSTEM

RENAL SYSTEM

ORGAN SYSTEM

PRODUCE,STORES,ELIM

ANATE URINE

MALE AND FEMALE-SIMILAR

LENGTH OF URETER-

DIFFERENT

URINARY SYSTEM

KidneysUreters

Urinary bladder

UrethraDetrusor

KIDNEYLie on the posterior abdominal wall

One on each side of the vertebral columnBehind the peritoneumBelow the diaphragm

Extend-12th thoracic vertebra-3rd lumbar vertebra

Protection-lower rib cageRight kidney usually slightly lower than the left

The KidneyAre

paired organs

Reddish in

colour

Bean shaped organ11cm

long,6cm wide,3c

m thick,150g weight

Fibroelastic renal

fascia

The kidneys held in place-

renal fat

5

RIGHT KIDNEY AND LEFT KIDNEY

Superiorly- the right adrenal gland

Anteriorly- the right lobe of the liver, the duodenum and the hepatic flexure of

colonPosteriorly- the diaphragm, and muscles

of the posterior abdominal wall

Superiorly- the left adrenal gland

Anteriorly- the spleen, stomach, pancreas, jejunum and splenic flexure of the colon

Posteriorly- the diaphragm and muscles of the posterior abdominal wall

Protection of the Kidneys

3 layers of connective

tissue:

Cortex

Fibrous Capsule

medulla

Renal cortex

Retroperitoneal space

9

• Funnel shaped• Distal branches-

calyces• Papilla at the

apex of a pyramidKidney RENAL

PELVIS

THE HILUM

concave medial border of the kidney where renal blood

vessels, nerve and lymph

vessels enter

10

Surface anatomy of the Kidney

Hilum is located on the medial surface

10 cm

5.5cm

3cm

11

Internal Structure of the Kidney

Renal pyramids

Renal papilla

Renal Columns

Renal Lobe

12

Walls of Pelvis

• contain smooth muscle

• lined with transitional epithelium

• Kidneys are made of nephrons, which are the functional unit of the kidney.

• The nephron ends at the collecting tubule

• Tubule-connective tissue,blood vessels,nerves,lymph vessel

Kidney-Nephron

-THE NEPHRONConsists-tubule closed at one

end-opening into a collecting

tubule-3cm long

-proximal convulated tubule-medullary loop(loop of henle)

-distal convulated tubule,leading into a collecting

duct14

A Nephron and associated Blood Vessel

15

Nephron-Tubular System

Proximal convoluted tubule

Descending loop of Henle

Ascending loop of Henle

Distal convoluted tubule

Collecting duct 16

Elimination of waste

Collecting duct unite-forms large ducts

Empty into minor calyces

Kidney-Hilum-renal artery

divides

Cortex-afferent arteriole

enters glomerular

capsule

Blood vessel-from

glomerulus is afferent arteriole

Breaks up into a second

cappilary network

Exchange occurs

Venus blood-leaves kidney

The Glomerulus

Wall and Capsule-single layer of flattened

epithelial tissue

-More permeable• The remainder-nephron and

collecting tubule-form by a single layer of specialiized cell

NURH 1023 - Urinary system 20

The Glomerulus

NURH 1023 - Urinary system 21

The Formation

of Urine

3 processes involved in the formation of urine.• Simple filtration

• Selective reabsorbtion• Hormonal control-

• Parathyroid hormone, calcitonin

• Anti diuretic hormone• Aldosterone• Secretion

22

Glomerular Filtration

• Through semi-permeable walls of glomerulus and glomerular capsule

• Fluid is forced out of capillaries and collected by the glomerular capsule

23

Selective reabsorption

Process by which the composition and volume of the glomerular filtrate are altered during its passage through the convoluted tubules, the medullary loop and the collecting tubule.

Carried out by epithelial cells

Materials that are reabsorbed include water, glucose and amino acids

25

26

Tubular Secretion• Occurs in the convoluted tubules• Adds materials to filtrate• Movement of materials from

peritubular capillaries into tubules• Materials secreted include K+ and H+

• This helps control pH

27

28

Ureters

Superiorly

Continuous with the renal pelvis

InferiorlyPass through the abdominal cavity, behind the peritoneum, infront of the psoas muscle, into the pelvic cavity ehere they enter the posterior wall of the bladder

25-30 cm in length with diameter 3mm

29

Further InformationThe urine

accumulates the pressure in the bladder rises,

the ureters compressed

and the openings occluded.

This prevents reflux of urine

into the ureters ( towards the

kidneys ) as the bladder fills.

During micturition,

pressure the muscular

bladder wall contracts.

30

31

Ureter- Cross Section

3 layers of tissue• Outer layer• Fibrous tissue

• Middle layer• Muscle

• Inner layer• Transitional

Epithelium

32

33

The Urinary Bladder

The urinary bladder is a sac which acts as a reservoir for urineIt lies in the pelvic cavity. Its size and position vary depending on the amount of urine it contains.When distended the bladder rises into the abdominal cavityCapacity approx. 700mL

34

Bladder

35

Structure of the Urinary Bladder

It is pear shaped

but becomes

oval shaped when

filled with urine

Composed of 3 layers of tissues:• The outer

layer of loose connective tissue, containing blood and lymphatic vessels and nerves, covered on the upper surface by the peritoneum

) The middle layer,

consisting of a mass of interlacing

smooth muscle fibres

and elastic tissue loosely

arranged in three layers. This is called the detrusor

muscle and it empties the

bladder when it contracts

3) The lining of

transitional

epithelium

36

Bladder

3 layers

Outer layer• Loose

connective tissue

Middle layer• Smooth

muscle and elastic fibres

Inner layer• Lined

with transitional epithelium

37

The Urethra

Is a canal that extends from the neck of the bladder

and its length differs in the

male and female

The male urethra is associated with the

urinary and the

reproductive system

The female urethra

opens at the external urethral

orifice just in front of the

vagina.

The external urethral orifice is

guarded by a sphincter

under voluntary

control

38

Urethra

• Female: 4cm long• Male:

14cm long

Anatomical differences

mean that male and female

urethras are different.

Extends from the base of the bladder

to the outside world.

39

The Structure of the Urethra

The urethra is composed of 3 layers of tissue:

• 1. A muscular coat• -continous with bladder• -origin from internal urethral

sphincter• -consist of elastic tissue and smooth

muscle• -under autonomic nerve control • 2. A thin spongy coat• - Submuocosa • - Contain blood vessels and nerve• 3. A lining of mucous membrane• - Continous bladder • - Lower part - Consist of stratified

squmous epithelium• - Continous externally with the skin

of the vulva40

Urethra

• Muscle layer

• Submucosa layer

• Mucosa

41

MICTURITION

Urinary Bladder – reservior for urine.

300-400ml urine accumulate – afferent

autonomic nerve fibres are stimulated

Infant - spinal reflex and micturition.

Micturition – Autonomic efferent fibres

convey impulses to the

bladder

• Contraction of the detrusor muscle

• Relaxation of the internal urethral sphincter

42

Contraction of the external urethral sphincter and muscle of the pelvic

floor- inhibit micturition

Awareness to pass urine

Sensory impules pass upward

Micturition reflex is stimulated

43

Micturition in Adult

Detrusor muscle contract

Reflex relaxation – internal sphincter

Voluntary relaxation – external sphincter

Assisted – increase pressure within the pelvic cavity

Achieved – lowering the diaphragm

-contracting the abdominal

muscle( Valsava’s manoeuvre)

44

REFERENCE

45

Pre-U Text STPM

Website-https//medical.com

Essential of Anatomy and 3th edition

SPM Biology-Reference Book