Urinary System Structure and Function

URINARY ORGANS include:

kidneys, ureters, urinary bladder, urethra

URINE: FORMED? FLOWS THROUGH? STORED? ELIMINATED VIA?

in the kidneys and flows through the ureters to the urinary bladder, which stores urine until t is eliminated from the body through the urethra

KIDNEY

bean shaped, retro peritoneal.....either of two bean-shaped excretory organs that filter wastes (especially urea) from the blood and excrete them and water in urine

kIDNEY: FOUND?

at waist level, between 12th thoracic vertebra and 3rd lumbar

WHAT PASES THROUGH THE RENAL HILUS?

the ureter, renal arteries, veins, nerves lymphatic

RENAL HILUS

the concave surface of each kidney faces the vertebral column and contains a vertical fissure called the renal hilud

HOW IS KIDNEY ATTACHED TO THE ABDONINAL WALL?

renal fascia attaches it

RENAL FASCIA

Outermost layer of the kidney composed of dense irregular tissue; anchors kidney to the back of the body wall

RENAL CAPSULE

a smooth transparent membrane the adheres tightly to the external aspect of the kidney, outside layer. think connective tirruse keeping substances inside.

ADIPOSE CAPSULE

used for padding and protection

3 MAIN REGIONS OF THE KIDNEY

cortex, medulla, sinus

NEPHRONS

structural and function units of the kidney that form urine

URINE DRAINS INTO....?

pappillary ducts that exit through the openings in the renal papilla

RENAL SINUS

a space or cavity that is adjacent to the medulla and extends to the renal hilus

MINOR CALYCES

small cup shaped cavities into which urine first enters. receives from the urine duct

HOW MANY MINOR AND MAJOR CALYCES?

8-18minor and 2-3 major

MAJOR CALYCES

drains into the renal pelvis, which is continuous wiht the ureter

WHAT TRAVELS THROUGH THE RENAL SINUS?

BLOOD VESSELS, LYMPHATIC, AND NERVES...the rest is adipose that fills it

URETERS:SIZE? LOCATED?DIAMETER?

25-30 cm long, behind peritoneum, 1-10mm diameter

HOW IS URINE PROPELLED THROUGH URETERS BY...?

peristalsis, hydrostatic pressure, gravity

URINARY BLADDER

saclike organ in which urine is stored before being excreted

URETHRA

duct through which urine is discharged in most mammals and which serves as the male genital duct

DETRUSOR MUSCLE

formed by 3 layer of muscles contracts and compress urinary bladder to expel urine into urethra

RUGAE

Ridges on the hard palate and the wall of the stomach

TRIGONE

inferior surface of urinary bladder contains 3 openings that form the trigonre

URETERAL OPENINGS

2 posterior openings

INTERNAL URETHRAL ORIFICE

anterior opening to the urethra

URINARY BLADDER: MALE VS WOMAN: LOCATION

males: bladdar is anterior to the rectum and posteror to the pubic symphysis. in females:urinary bladdar is anterior to the vagina, inferior to the uterus and posterior to the pubic symthesis

URETHRA

carries urine from the internal urethral oriffice to the external urethral oriffice

INTERNAL URETHRAL SPHINCTER

located at the neck of the urinary bladder, these smooth muscle fibers provide involuntary control over the discharge of urine from the bladder

EXTERNAL URETHRAL SPHINCTER

sphincter muscle or valve that is more inferiorly located on the bladder. helps to control the outflow of urine from the bladder. This sphincter is voluntarily controlled

MICTURITION

detrusor muscle contracts and forces urine out of the urinary bladder, and the internl and external urethral sphincters relax to allow passage of urine.

FEMALE URETHRAL LENGTH

4cm

MALE URETHRAL LENGTH

15-20 cm

MALE URETHRA: REGIONS?

prostatic urethra, membranous urethra, spongy (penile) urethra

NEPHRON

1 million nephrons in kidney filter blood from urine. it contains a RENAL CORPUS FILTRATE that filter blood and a RENAL TUBULE that modifies the filtrate o form urine

RENAL CORPUSCLE: LOCATED? CONSISTS OF?

located in the renal cortex. consists of glomerulus and a glomerular capsule, a cup shaped epithelial membrane surrounding the glomerulus

CAPSULAR SPACE/GLOMERULAR CAVITY

blood is foltered into here. it is not called FILTRATE and it drains into the renal tubule

RENAL TUBULE: 3 STRUCTURAL AND FUNCTIONAL SECTIONS

proximal convoluted tubule, loop of henle, distal convoluted tubule

URINE:DEFINITION

distal convoluted tubules from several nephrons drain the liquid (now called urine) into COLLECTING DUCTS that descend through the renal pyraids and mrege to form larger PAPILLARY DUCTS

AFFERENT ARTERIOLE

delivers systemic blood to the glomerulus

EFFERENT ARTERIOLE

smaller in diameter. receives blood from the glomerulus. delivers blood to a second capillary bed, the PERITUBULAR CAPILLARY NETWORK that entwines the renal tubule

2 TYPES OF NEPHRONS

CORTICAL NEPHRON (short loops of Henle that descend slightly into the medulla) JUXTAMEDULLARY NEPHRON (long loops of Henle that extend deep into the medulla)

VASA RECTA

long capillary loops that extend from the efferent arteriole

KIDNEY: GLOMERULAR (BOWMANS) CAPSULE: COMPOSED OF?

visceral and parietal epithelial layer. both are simple squamous epithelium

KIDNEY: VISCERAL LAYER:CONTAINS?

forms part of the filtration membrane, is adjacent to the glomerulus. contains podocytes (foot like projections of simple squamous epithelium)

KIDNEY: PARIETAL LAYER

forms a funnel-like structure that collects the filtrate within the capsular space.

URETERS: COMPOSED OF3 LAYERS?

MUCOSA that lines the lumen, MUSCULARIS a msucular layer, OUTER ADVENTITIAL LAYER

MUCOSA: CONTAINS?

contains Transitional epithelium that can distend to accommodate urine, and a n underlying lamina propria of areolar connective tissue

MUSCULARIS: CONTAINS WHAT KIND OF MUSCLE?

smooth muscle

PERISTALSIS: FUNCTION

the function of the muscularis layer, moves urine from the renal pelvis to the urinary bladder

ADVENTITIA: FUNCTION

secures the ureters in place

EPITHELIUM OF MUCOSA IS?

trnsitional epithelium

T or F: urinary bladder contains same layers as the ureter

TRUE

EPUTHELIUM OF MUSCULARIS?

smooth muscle

T OR F: contraction of the muscularis layer forces urine out of the urinary bladder

TRUE

T OR F: the urethra consists of a mucosa surrounded by a muscularis layer of circular smooth muscle

TRUE

CHANGES IN EPITHELIUM ALONG THE COURSE OF THE URETHRA

near urinary bladder: transitional, distally: becomes stratified columnar or pseudo stratified columnar, near the external urethral orifice: stratified squamous epithelium