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ANATOMY & PHYSIOLOGY II BIO 212:

Dr. Lawrence G. Altman www.lawrencegaltman.com Some illustrations are courtesy of McGraw-Hill.

CHAPTER 20 Lecture:

URINARY

Part 1 Part 2

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URINARY  SYSTEM  General  Functions      Maintenance  of  Homeostasis  

   

   

Regulation  of  body  fluid  composition:      water  balance/ions      acid-­‐base  balance      

Elimination  of  body  wastes:      cellular  metabolism      

phagocytosis      foreign  chemicals,  drugs  &  food  additives      

WASTE      PRODUCTS  

Minor  endocrine  function:      secretion  of  erythropoietin    and  renin      

blood      pressure      

maintenance  activation  of  vitamin  D      

(necessary  for  calcium  absorption  in  SI)      

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Representative  Waste  Products  Nitrogenous  waste  from  Protein:      

UREA              

Muscle  activities:      CREATININE              

Nucleic  Acid  :      URIC  ACID              

Hemoglobin  Breakdown:      BILIRUBIN  and  other      UROCHROMES  

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URINE  COMPOSITION  

UREA      CREATININE      AMMONIA      URIC  ACID  

30  grams  

LESS  than      2  grams  

Remainder:    Inorganic  Salts  

per  24  hrs.  

pH=  4.6  -­‐  8:      -­‐>  infection  or           renal  failure.      <-­‐  diabetes           mellitus,           emphysema           &  starvation  

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http://health.clevelandclinic.org/2013/10/what-­‐the-­‐color-­‐of-­‐your-­‐urine-­‐says-­‐about-­‐you-­‐infographic/  

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Urinary  system  not  alone  in  waste  removal-­‐-­‐-­‐  

RESPIRATORY   carbon  dioxide  and  water  

INTEGUMENTARY   nitrogen  compounds,  water  and  electrolytes  

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 *  primary  function  of  sweat  glands  is  temperature  regulation.  

DIGESTIVE   digestive  wastes  bile  pigments  heavy  metal  salts  

Urinary:  most  important  for-­‐  water  and  electrolyte  balance  

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Adrenal Gland

Kidney  location:  

Retroperitoneal  

General  Anatomy  

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URINARY  EPITHELIUM  (TRANSITIONAL  or  UROTHELIUM)  

Interdigitating  cells  junctions;  (distension  possible)  

Found  within  conducting     passages  of  the  urinary  system.  

Impermeable  to  urine  which  is,   although  sterile,  potentially  toxic.  

Prevents  water  from  being  drawn   into  hypertonic  urine.  

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URETERS    subject  to  peristaltic  waves  initiated  in  pelvis;      mostly  due  to  stretch  -­‐-­‐>  local  smooth  muscle.  

RELAXED  URETER  

Three  (3)  layers:  MUCOSA:  -­‐Transitional  epithelium  -­‐Lamina  propria  

MUSCULARIS:  (smooth  muscle)  -­‐inner:  longitudinal  -­‐outer:  circular   Additional  outer  longitudinal  

layer  in  lower  third  of  ureter.  

ADVENTITIA:  -­‐Blood  vessels  -­‐Lymphatics  -­‐Nerves  

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Bladder  urge    activated  at  300  ml  

Can  be  consciously  overrode  Completely  full  bladder  

contains  3X  more  

URINARY  BLADDER  

Triangle formed by the openings of the ureters and urethra

(Smooth muscle)

(Striated muscle)

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URINARY  BLADDER  

A  

Three  (3)  layers:  MUCOSA:  -­‐Transitional  epithelium  -­‐Lamina  propria  

MUSCULARIS:  (smooth  muscle)  -­‐inner:  longitudinal  -­‐outer:  circular  

Additional  outer  layer  of  longitudinal  smooth  muscle  (as  found  in  bottom  third  of  ureter)  continues  in  bladder.  

-­‐outer:  longitudinal  DETRUSOR  Muscle  

ADVENTITIA:  -­‐Blood  vessels  -­‐Lymphatics  -­‐Nerves  

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URETHRA   Urethral  glands  Females:  

anterior  to  vaginal  opening;  posterior  to  clitoris  Opening:  ext.  urethral  orifice  (urinary  meatus)  

 between  labia  minora  only  4  cm  in  length  (<  2  in.)  Short  distance  to  bladder:  frequent  urinary  infection  

Males:  approximately  20  cm  (8  in.)  in  length  Transports  sperm  as  well  as  urine.  Three  (3)  regions:  

1.   Prostatic  urethra;    2.5  cm  (1  in.)  

3.   Penile  (spongy)  urethra;    15  cm  (6  in.)  2.   Membranous  urethra;    2.0  cm  (<  1  in.)  

SCHEMATIC:  MALE  

URETHRA  

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URETHRA:  Male  

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MICTURITION  ("voiding"  or  urination)  

Distension  of  bladder.  activation  of  stretch  receptors-­‐    triggers  a  visceral  reflex  arch:    

Afferent  impulses  -­‐-­‐-­‐>  sacral  region  of  SC  

Efferent  impulses   Bladder  Pelvic  Splanchnic  Nerves  

(Parasympathetic)  

Result:  Detrusor  muscle  contracts  Internal  sphincter  relaxes  

Override:  Ext.  sphincter  

INCONTINENCE:  Loss  of  

bladder  control  

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General  Anatomy:    external       KIDNEY  

HILUM:  Indented  region-­‐      Passage  of:      blood  vessels      nerves      ureter  

RENAL  FASCIA  

ADIPOSE  

RENAL  CAPSULE  

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General  Anatomy:    external  KIDNEY  

Liver  

Parietal  Peritoneum  

(behind  it)  

Renal  Fascia  

Large  Intestine  

Renal  Fascia  

Adrenal  Gland  

Renal  Capsule  

Adipose  

Coxa  

Back  half  of  Sagittal  cut  

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KIDNEY  BLOOD  SUPPLY  RENAL  artery  

SEGMENTAL  arteries  *  

*  not  listed  in  your  books  

INTERLOBAR  arteries  ARCUATE  arteries  

INTERLOBULAR  arteries  

ARCUATE  artery  

AFFERENT  arterioles  GLOMERULUS  

EFFERENT  arterioles  PERITUBULAR  capillaries  

VENULES  INTERLOBULAR  veins  

ARCUATE  veins  INTERLOBAR  veins  SEGMENTAL  veins  *  

RENAL  Vein  

In some books aka Cortical Radiate arteries

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END  

In some books aka Cortical Radiate arteries