ExcretorySystemPart 1

Excretion Process that rids body of

metabolic wastes:Preformed by:

a) Skinb) Liverc) Lungsd) Kidney f) Intestines

a) Skin Primarily to cool body Perspiration includes:

i) waterii) Salt (K+,Na+,Ca2+,Mg2+,Fe+)iii) urea

b) Liver Excretes:

i) bile (breakdown of RBC)ii) urochrome (breakdown of heme)

gives yellow color of urine

c) Lungs Excretes:

i) CO2

ii) some H2O

d) Kidneys Excretes nitrogenous wastes:i) ammonia (NH3) – deamination of amino acid toxic; therefore converted to ureaii) uric acid - nucleic acid breakdowniii) creatinine – from creatinine phosphate in muscle metabolism

d) Kidneys Also excretes:

i) ionsii) wateriii) detoxified drugs (penicillin,

histamines)

Urine is composed mainly of urea (~3%), salts (~2%), and water (~95%)

e) Intestines Excretes iron and calcium salts via feces

Major Organs

Kidney

Ureter

Urethra

Bladder

Renal arteryRenal Vein

Functions of major organOrgans FunctionKidney

Renal Artery

Renal Vein

Ureter

Bladder

Urethra

- Removal of metabolic waste- Maintain blood volume- Maintain blood pH- Brings blood to kidneys

- Brings blood away from kidneys

- 25cm tube from kidney to bladder via peristalsis

- Hold up to 600mL – 1000 mL of urine

- Hollow and muscular- Tube carrying urine out from bladder- ♀ ~1” long (carries urine only)- ♂ ~ 6” long (carries semen and urine)

Adrenal Gland and KidneyAdrenal Cortex- Secretes hormone Aldosterone

Adrenal Medulla- Secretes adrenaline/noradrenalin

- Epinephrine/norepinephrine

Kidney

Renal pelvis

Renal Medulla

Renal PyramidVideo