Shumail Ayub Qureshi BS ZOOLOGY

1. PATTERN OF NITROGENOUS
WASTE AND PHYLO
GENECTICAL DEVELOPMENT
OF EXCRETORY SYSTEM
Shumail Ayub
Qureshi
Enrollment#40
BS ZOOLOGY 5TH
SEMESTER

2. EXCRETORY SYSTEM
 The well organized and developed system in living organisms for the removal of waste
material from the body in order to maintainces of HOMEOSTATICS named as
EXCRETORY SYSTEM.
 The process of removal of waste materials called as EXCRETION.
 It is the one of the distinguished character of living organisms.
 In living organisms nitrogenous waste is usually excreted because our body has high
percent of nutrition intake as well as body structures contained nitrogen as back bone
that’s why living organisms mostly excreted nitrogenous waste.
 Uriniferous tubules are divided into proximal convoluted tubule distal and collecting
duct.

3. PATTERN OF NITROGENOUS WASTE
PRODUCT
AMMONIA
Elimination of nitrogenous
waste that is ammonia called
as AMMONOTELISM.
Animals whom excreted it
named as AMMONOTELIC.
 Highly toxic.
 Water souble.
 Large amount of water
needed for its elimination
appox 500ml per N BOND
in it.
 Aquatic animals,bony
fishes,aquatics amphibians
UREA
Removal in the form of nitrogenous
waste as urea called as
URE0TELIAM.
Animals excreted it named as
UREOTELIC.
 LESS toxic
 Less water appox 50ml per N
BOND.
 Remained in body for brief period
of time
 HUMANS,turtle,frogs,sharks
URIC ACID
Excreted in the form of nitrogenous
waste as uric acid called as
URICOTELISM.
Animals named as URICOTELIC.
 DO NOT need more water.
 Crystal form.
 insoluble in water. Appox 5ml.
 Conserved water.
 Birds,snails,cockrocks,lizard,snak
es.

5. EXCRETORY PRODUCTS
Excretory product could be;
I. Urea
II. Uric acid
III. Ammonia
IV. Guanine
V. Creatinine
VI. Water
VII. Bilirubin
VIII. Orinth uric acid
IX. Allantoin

6. GUANINE
• First ammonia converted into guanine then excreted as GUANOTELISM.
• Insouble in water
• No water needed for its excretion
• Spider,birds some,some reptiles.
• UREA CYCLE
• Carbonyl phosphate/synthatease
• Ornithnine/transcarbonylase
• Citrulline/citrulase
• Arginosuccinate/arginase
• Arginine
• Urea/H2O

9. URIC ACID CYCLE
KEY
• AMP;adenosine monophosphate
• APRT;adeninephosphoribosyl tranferse
• GMP;guaninemonophosphate
• HGPRT;hyposxanthie guaninephosphate
• IMP;inosive monophosphate
• PRPP;5 phosphoribosylphosphate
• PRPS;PRPs synthatase
• XO;xanthine oxidase

11. PHYLOGENCTICAL DEVELOPMENT OF
EXCRETORY SYSTEM
EVOLUTION FROM UNICELLULAR
CONTRACTILE VACUOLE TOWARDS META
NEPHRONIC KIDNEY

12. CONTRACTILE VACUOLE IN UNICELLULAR
• Contractile vacuole present in unicellular organisms
• Main function as excretion
• It is consider as the first excretory system ever
• Modification in contractile vacuole leads the formation of metanephronic kidney in
vertebrates
• Contractile vacuole works on the transport mechanism named as endo or exocytosis
• It is consider as the most primitive form of excretion.